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Jerilynn C Prior


cemcor@interchange.ubc.ca

Journal articles

2011
W D Leslie, C Berger, L Langsetmo, L M Lix, J D Adachi, D A Hanley, G Ioannidis, R G Josse, C S Kovacs, T Towheed, S Kaiser, W P Olszynski, J C Prior, S Jamal, N Kreiger, D Goltzman (2011)  Construction and validation of a simplified fracture risk assessment tool for Canadian women and men: results from the CaMos and Manitoba cohorts.   Osteoporos Int 22: 6. 1873-1883 Jun  
Abstract: A procedure for creating a simplified version of fracture risk assessment tool (FRAX®) is described. Calibration, fracture prediction, and concordance were compared with the full FRAX tool using two large, complementary Canadian datasets.
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Lisa Langsetmo, Tuan V Nguyen, Nguyen D Nguyen, Christopher S Kovacs, Jerilynn C Prior, Jacqueline R Center, Suzanne Morin, Robert G Josse, Jonathan D Adachi, David A Hanley, John A Eisman (2011)  Independent external validation of nomograms for predicting risk of low-trauma fracture and hip fracture.   CMAJ 183: 2. E107-E114 Feb  
Abstract: A set of nomograms based on the Dubbo Osteoporosis Epidemiology Study predicts the five- and ten-year absolute risk of fracture using age, bone mineral density and history of falls and low-trauma fracture. We assessed the discrimination and calibration of these nomograms among participants in the Canadian Multicentre Osteoporosis Study.
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Lisa Langsetmo, David A Hanley, Jerilynn C Prior, Susan I Barr, Tassos Anastassiades, Tanveer Towheed, David Goltzman, Suzanne Morin, Suzette Poliquin, Nancy Kreiger (2011)  Dietary patterns and incident low-trauma fractures in postmenopausal women and men aged ≥ 50 y: a population-based cohort study.   Am J Clin Nutr 93: 1. 192-199 Jan  
Abstract: Previous research has shown that dietary patterns are related to the risk of several adverse health outcomes, but the relation of these patterns to skeletal fragility is not well understood.
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William D Leslie, Christopher S Kovacs, Wojciech P Olszynski, Tanveer Towheed, Stephanie M Kaiser, Jerilynn C Prior, Robert G Josse, Sophie A Jamal, Nancy Kreiger, David Goltzman (2011)  Spine-Hip T-Score Difference Predicts Major Osteoporotic Fracture Risk Independent of FRAX(®): A Population-Based Report From CAMOS.   J Clin Densitom Jun  
Abstract: The WHO fracture risk assessment tool (FRAX(®)) estimates an individual's 10-yr major osteoporotic and hip fracture probabilities. When bone mineral density (BMD) is included in the FRAX calculation, only the femoral neck measurement can be used. Recently, a procedure was reported for adjusting major osteoporotic fracture probability from FRAX with femoral neck BMD based on the difference (offset) between the lumbar spine and the femoral neck T-score values. The objective of the current analysis was to independently evaluate this algorithm in a population-based cohort of 4575 women and 1813 men aged 50yr and older from the Canadian Multicentre Osteoporosis Study. For women and men combined, there was a 15% (95% confidence interval 7-24%) increase in major osteoporotic fracture risk for each offset T-score after adjusting for FRAX probability calculated with femoral neck BMD. The effect was stronger in women than men, but a significant sex interaction was not detected. Among the full cohort, 5.5% had their risk category reclassified after using the offset adjustment. Sex- and age-dependent offsets (equivalent to an offset based on Z-scores) showed improved risk classification among individuals designated to be at moderate risk with the conventional FRAX probability measurement. In summary, the T-score difference between the lumbar spine and femoral neck is an independent risk factor for major osteoporotic fractures that is independent of the FRAX probability calculated with femoral neck BMD.
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Jerilynn C Prior, Christine L Hitchcock (2011)  The endocrinology of perimenopause: need for a paradigm shift.   Front Biosci (Schol Ed) 3: 474-486 01  
Abstract: Perimenopause, rather than a time of declining estrogen, is characterized by three major hormonal changes that may begin in regularly menstruating women in their mid-thirties: erratically higher estradiol levels, decreased progesterone levels (in normally ovulatory, short luteal phase or anovulatory cycles), and disturbed ovarian-pituitary-hypothalamic feedback relationships. Recent data show that approximately a third of all perimenopausal cycles have a major surge in estradiol occurring de novo during the luteal phase. This phenomenon, named "luteal out of phase (LOOP)" event, may explain a large proportion of symptoms and signs for symptomatic perimenopausal women. Large urinary hormone data-sets from women studied yearly over a number of years in the Study of Women Across the Nation (SWAN) and in the Tremin data will eventually provide a more clear prospective understanding of within-woman hormonal changes. Predicting menopause proximity with FSH or Inhibin B levels is documented to be ineffective. Anti-Mullerian hormone levels may prove predictive. Finally, there is an urgent need to change perimenopause understandings, language and therapies used for midlife women's symptoms to reflect these hormonal changes.
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2010
Elyse Battistella, Shirin Kalyan, Jerilynn C Prior (2010)  Evaluation of methods and costs associated with recruiting healthy women volunteers to a study of ovulation.   J Womens Health (Larchmt) 19: 8. 1519-1524 Aug  
Abstract: OBJECTIVE: We address the crucial and challenging task of anticipating the resources needed to recruit eligible participants for research. We provide our analysis of various recruitment strategies and their cost-effectiveness in our experience in enrolling 610 women for an observational study on ovulation. METHODS: We assess the cost-effectiveness and success of multiple recruitment strategies we employed and provide the estimated cost of labor and materials for each. At enrollment, all participants were asked an open-ended question about how they learned about the study. No financial compensation was provided, but participants received personal hormonal analysis results on completion. RESULTS: Of the 610 enrolled women, 552 provided information on how they learned about the study. The total cost of recruitment was $7645.11, which includes 183 staff hours. The average recruitment cost per participant was $12.53 (ranging from $0 to $118.63). The two methods with the lowest total costs resulted in enrollment of 48% of the recruitment goal using only 0.3% of the budget. In contrast, the two methods with the highest total costs produced 13% of the participants needed but consumed over 72% of the budget. CONCLUSIONS: Low-cost methods are a viable, practical source for attracting healthy women for observational research. Investigators are encouraged to track sources of recruitment and analyze their data at regular intervals during the recruitment phase. Sharing comprehensive recruitment data will assist other researchers to better estimate the resources needed to meet their enrollment goal, leading to more efficient use of time and funding.
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E Kingwell, J C Prior, P A Ratner, S M Kennedy (2010)  Direct-to-participant feedback and awareness of bone mineral density testing results in a population-based sample of mid-aged Canadians.   Osteoporos Int 21: 2. 307-319 Feb  
Abstract: This population-based study of mid-aged Canadians assessed awareness of diagnosis by bone mineral density (BMD) following dual-energy X-ray absorptiometry (DXA) testing and compared the effects of feedback only to the physician with direct-to-participant feedback. Poor recall of osteoporosis results was observed irrespective of the feedback destination, but direct-to-participant feedback improved recall of borderline or normal results. INTRODUCTION: BMD testing provides information about fracture risk. This study assessed whether awareness of results, in a random population sample of mid-aged Canadians, differed if results were provided to physicians only or directly to participants. METHODS: Prospective cohort study of 2,678 women and men aged 40-60 years from the Canadian Multicentre Osteoporosis Study. Participants completed hip and spine DXA and interviewer-administered questionnaires regarding demographics and osteoporosis risk factors. Lateral spine X-rays were conducted on those > or =50 years of age. All test results were reported to the participant, the family physician or both. Associations between BMD results, feedback destination and correct self-report results, 3 years later, were assessed using logistic regression while adjusting for potential confounders. RESULTS: Only 25% of men and 33% of women correctly reported their osteoporosis diagnoses. Direct-to-participant vs. physician-only reports did not improve recall of osteoporosis diagnosis but improved recall of borderline or normal BMD. Older (vs. younger) men and men with prevalent vertebral fractures demonstrated better recall of their osteoporosis diagnosis. CONCLUSIONS: Recall of low BMD results was poor, despite direct-to-participant feedback and even in the presence of other osteoporosis risk factors. Direct-to-participant feedback may improve awareness of borderline or normal BMD results.
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Shirin Kalyan, Jerilynn C Prior (2010)  Bone changes and fracture related to menstrual cycles and ovulation.   Crit Rev Eukaryot Gene Expr 20: 3. 213-233  
Abstract: Women's menstrual cycles and bone remodeling are linked in part by their co-dependency on the stress- and resource-associated variables that govern both of their cyclical natures. Therefore, it is not surprising that evolution has resulted in the same signaling molecules and pathways that regulate normal ovarian function to be involved in bone remodeling and turnover. This review will first provide an overview of the normal menstrual cycle, its modification by age and ovulatory disturbances, and how it parallels bone remodeling. Epidemiological and clinical evidence will be presented that link bone remodeling, strength, and fractures with women's history of reproductive and menstrual cycle characteristics. This combined evidence will then be presented alongside a synthesis of current concepts derived from basic science investigations focused on understanding the molecular mechanisms underlying the influence of ovarian factors on bone physiology. Osteoporosis is a significant source of morbidity for older women. The data presented in this review suggest that a woman's reproductive cycle and ovulatory characteristics foreshadow the future health of her bones. More importantly, identifying the key mechanisms underlying reproductive and bone health would not only provide essential preventative strategies, but may also uncover attractive targets for the treatment of osteoporosis.
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Vanadin Seifert-Klauss, Jerilynn C Prior (2010)  Progesterone and bone: actions promoting bone health in women.   J Osteoporos 2010: 10  
Abstract: Estradiol (E(2)) and progesterone (P(4)) collaborate within bone remodelling on resorption (E(2)) and formation (P(4)). We integrate evidence that P(4) may prevent and, with antiresorptives, treat women's osteoporosis. P(4) stimulates osteoblast differentiation in vitro. Menarche (E(2)) and onset of ovulation (P(4)) both contribute to peak BMD. Meta-analysis of 5 studies confirms that regularly cycling premenopausal women lose bone mineral density (BMD) related to subclinical ovulatory disturbances (SODs). Cyclic progestin prevents bone loss in healthy premenopausal women with amenorrhea or SOD. BMD loss is more rapid in perimenopause than postmenopause-decreased bone formation due to P(4) deficiency contributes. In 4 placebo-controlled RCTs, BMD loss is not prevented by P(4) in postmenopausal women with increased bone turnover. However, 5 studies of E(2)-MPA co-therapy show greater BMD increases versus E(2) alone. P(4) fracture data are lacking. P(4) prevents bone loss in pre- and possibly perimenopausal women; progesterone co-therapy with antiresorptives may increase bone formation and BMD.
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Jennifer L Bedford, Jerilynn C Prior, Susan I Barr (2010)  A prospective exploration of cognitive dietary restraint, subclinical ovulatory disturbances, cortisol, and change in bone density over two years in healthy young women.   J Clin Endocrinol Metab 95: 7. 3291-3299 Jul  
Abstract: CONTEXT: Cross-sectional studies have found associations among elevated cognitive dietary restraint (CDR), increased ovulatory disturbances, and lower bone mass, possibly mediated by cortisol. OBJECTIVE: To determine whether healthy young women with higher CDR have more menstrual cycles with subclinical ovulatory disturbances (SOD), elevated 24-h urinary free cortisol (UFC), and less positive 2-yr areal bone mineral density change (Delta-aBMD). DESIGN, SETTING, AND PARTICIPANTS: We conducted a 2-yr longitudinal study of 123 healthy, community-dwelling, nonobese, regularly menstruating women aged 19-35 yr. MAIN OUTCOME MEASURES: Key variables were Three Factor Eating Questionnaire Restraint score, percent of cycles with anvoluation and/or luteal phase length <10 d (%SOD), UFC, and Delta-aBMD at the lumbar spine (L1-L4), total hip, and whole body. Anthropometrics, general stress, physical activity, and energy intake were measured. Adjusting for potential confounders, differences were examined by general linear modeling using median split of CDR score and %SOD. RESULTS: Women with higher CDR had higher %SOD (56 vs. 34%, P < 0.001) and higher UFC (28.0 vs. 24.0 microg/d, P = 0.021). Delta-aBMD did not differ by CDR. Women with higher %SOD had less positive Delta-aBMD at L1-L4 (0.7 vs. 1.9%, P = 0.034) and hip (-0.6 vs. 0.9%, P = 0.001), and higher CDR score (8.7 vs. 7.1, P = 0.04). Physical activity, general stress, body mass index, and energy intake did not explain differences by CDR or %SOD. UFC was not associated with %SOD or Delta-aBMD. CONCLUSION: Women with more frequent SOD reported higher CDR and experienced less positive Delta-aBMD. Although women with higher CDR had higher UFC, the mechanism linking CDR, SOD, and aBMD is not clear.
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Claudie Berger, David Goltzman, Lisa Langsetmo, Lawrence Joseph, Stuart Jackson, Nancy Kreiger, Alan Tenenhouse, K Shawn Davison, Robert G Josse, Jerilynn C Prior, David A Hanley (2010)  Peak bone mass from longitudinal data: implications for the prevalence, pathophysiology, and diagnosis of osteoporosis.   J Bone Miner Res 25: 9. 1948-1957 Sep  
Abstract: We estimated peak bone mass (PBM) in 615 women and 527 men aged 16 to 40 years using longitudinal data from the Canadian Multicentre Osteoporosis Study (CaMos). Individual rates of change were averaged to find the mean rate of change for each baseline age. The age range for PBM was defined as the period during which bone mineral density (BMD) was stable. PBM was estimated via hierarchical models, weighted according to 2006 Canadian Census data. Lumbar spine PBM (1.046 ± 0.123 g/cm(2)) occurred at ages 33 to 40 years in women and at 19 to 33 years in men (1.066 ± 0.129 g/cm(2)). Total hip PBM (0.981 ± 0.122 g/cm(2)) occurred at ages 16 to 19 years in women and 19 to 21 years in men (1.093 ± 0.169 g/cm(2)). Analysis of Canadian geographic variation revealed that the levels of PBM and of mean BMD in those over age 65 sometimes were discordant, suggesting that PBM and subsequent rates of bone loss may be subject to different genetic and/or environmental influences. Based on our longitudinally estimated PBM values, the estimated Canadian prevalences of osteoporosis (T-score < -2.5) were 12.0% (L(1)-L(4)) and 9.1% (total hip) in women aged 50 years and older and 2.9% (L(1)-L(4)) and 0.9% (total hip) in men aged 50 years and older. These were higher than prevalences using cross-sectional PBM data. In summary, we found that the age at which PBM is achieved varies by sex and skeletal site, and different reference values for PBM lead to different estimates of the prevalence of osteoporosis. Furthermore, lack of concordance of PBM and BMD over age 65 suggests different determinants of PBM and subsequent bone loss.
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Shirin Kalyan, Christine L Hitchcock, Sandra Sirrs, Morris Pudek, Jerilynn C Prior (2010)  Cardiovascular and metabolic effects of medroxyprogesterone acetate versus conjugated equine estrogen after premenopausal hysterectomy with bilateral ovariectomy.   Pharmacotherapy 30: 5. 442-452 May  
Abstract: STUDY OBJECTIVE: To compare the cardiovascular and metabolic effects of medroxyprogesterone acetate (MPA) with those of conjugated equine estrogen (CEE) as single-hormone therapies in women who underwent hysterectomy with bilateral ovariectomy. DESIGN: Secondary analysis of a 12-month, double-blind, randomized, parallel-therapy trial. SETTING: Four teaching hospitals and one community hospital in Vancouver, Canada. PARTICIPANTS: Thirty-three healthy women who underwent premenopausal hysterectomy with bilateral ovariectomy. INTERVENTION: Subjects received either MPA 10 mg/day (18 women) or CEE 0.6 mg/day (15 women) for 12 months, started immediately after hysterectomy with bilateral ovariectomy. MEASUREMENTS AND MAIN RESULTS: Lipid profiles (high-density lipoprotein cholesterol [HDL], total cholesterol, apolipoprotein B, and triglyceride levels), homeostatic measures (hemoglobin A(1c) and fasting blood glucose level), hormone levels (free and bioavailable testosterone, cortisol, sex hormone-binding globulin [SHBG], and dehydroepiandrosterone sulfate), inflammatory markers (C-reactive protein [CRP] and serum albumin levels), and anthropometric measures (body mass index [BMI], truncal fat, and total body fat) were assessed over the 12-month period. After 12 months, the women assigned to MPA had lesser increases in BMI (p=0.04), triglyceride (p=0.003), HDL (p<0.0005), SHBG (p<0.0005), total testosterone (p=0.003), and CRP values (p=0.01) and higher serum albumin levels (p<0.0005) compared with the women receiving CEE. CONCLUSION: Therapy with CEE, but not MPA, after surgical menopause appears to predispose healthy women to low-grade inflammation, as evidenced by its independent associations with elevated CRP and reduced albumin levels. In women treated with MPA, the favorable levels of inflammatory markers, BMI, and triglyceride levels need to be confirmed in larger controlled trials, as progesterone therapy may provide a safe and effective alternative to estrogen for vasomotor symptoms in women with surgical menopause.
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Lisa Langsetmo, Suzette Poliquin, David A Hanley, Jerilynn C Prior, Susan Barr, Tassos Anastassiades, Tanveer Towheed, David Goltzman, Nancy Kreiger (2010)  Dietary patterns in Canadian men and women ages 25 and older: relationship to demographics, body mass index, and bone mineral density.   BMC Musculoskelet Disord 11: 01  
Abstract: BACKGROUND: Previous research has shown that underlying dietary patterns are related to the risk of many different adverse health outcomes, but the relationship of these underlying patterns to skeletal fragility is not well understood. The objective of the study was to determine whether dietary patterns in men (ages 25-49, 50+) and women (pre-menopause, post-menopause) are related to femoral neck bone mineral density (BMD) independently of other lifestyle variables, and whether this relationship is mediated by body mass index. METHODS: We performed an analysis of 1928 men and 4611 women participants in the Canadian Multicentre Osteoporosis Study, a randomly selected population-based longitudinal cohort. We determined dietary patterns based on the self-administered food frequency questionnaires in year 2 of the study (1997-99). Our primary outcome was BMD as measured by dual x-ray absorptiometry in year 5 of the study (2000-02). RESULTS: We identified two underlying dietary patterns using factor analysis and then derived factor scores. The first factor (nutrient dense) was most strongly associated with intake of fruits, vegetables, and whole grains. The second factor (energy dense) was most strongly associated with intake of soft drinks, potato chips and French fries, certain meats (hamburger, hot dog, lunch meat, bacon, and sausage), and certain desserts (doughnuts, chocolate, ice cream). The energy dense factor was associated with higher body mass index independent of other demographic and lifestyle factors, and body mass index was a strong independent predictor of BMD. Surprisingly, we did not find a similar positive association between diet and BMD. In fact, when adjusted for body mass index, each standard deviation increase in the energy dense score was associated with a BMD decrease of 0.009 (95% CI: 0.002, 0.016) g/cm(2) for men 50+ years old and 0.004 (95% CI: 0.000, 0.008) g/cm(2) for postmenopausal women. In contrast, for men 25-49 years old, each standard deviation increase in the nutrient dense score, adjusted for body mass index, was associated with a BMD increase of 0.012 (95% CI: 0.002, 0.022) g/cm(2). CONCLUSIONS: In summary, we found no consistent relationship between diet and BMD despite finding a positive association between a diet high in energy dense foods and higher body mass index and a strong correlation between body mass index and BMD. Our data suggest that some factor related to the energy dense dietary pattern may partially offset the advantages of higher body mass index with regard to bone health.
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Sophie A Jamal, Victoria J D Swan, Jacques P Brown, David A Hanley, Jerilynn C Prior, Alexandra Papaioannou, Lisa Langsetmo, Robert G Josse (2010)  Kidney function and rate of bone loss at the hip and spine: the Canadian Multicentre Osteoporosis Study.   Am J Kidney Dis 55: 2. 291-299 Feb  
Abstract: BACKGROUND: The relationship between kidney function and bone loss is unclear. STUDY DESIGN: A prospective observational study. SETTING & PARTICIPANTS: 191 men and 444 women aged > or = 50 years participating in a population-based observational study designed to determine risk factors for bone loss and fractures. PREDICTORS: The primary predictor of change in bone mineral density (BMD) was estimated creatinine clearance (using the Cockcroft-Gault formula) measured at baseline and stratified by quartiles. Our secondary predictor was estimated glomerular filtration rate using the Modification of Diet in Renal Disease Study equation, also stratified by quartiles. OUTCOMES & MEASUREMENTS: Changes in BMD at the lumbar spine, total hip, and femoral neck during 5 years. RESULTS: Compared with participants in the first quartile of estimated creatinine clearance (>101.2 mL/min), those in remaining quartiles were older (quartile 1, 50.0 years; quartile 2 [101.2-83.4 mL/min], 54.7 years; quartile 3 [83.4-68.3 mL/min], 60.5 years; and quartile 4 [<68.3 mL/min], 68.3 years); weighed less; reported more sedentary hours; were less likely to report excellent, very good, or good self-reported health; consumed less caffeine; and had lower serum calcium and phosphate and higher serum parathyroid hormone levels. After adjusting for age, weight, sex, baseline BMD, and these differences, compared with those in the first quartile, those in the fourth quartile had decreases in BMD of 0.08 g/cm(2) (95% CI, 0.04-0.1) at the lumbar spine, 0.08 g/cm(2) (95% CI, 0.06-0.1) at the femoral neck, and 0.09 g/cm(2) (95% CI, 0.07-0.1) at the total hip. Bone loss did not increase with worsening kidney function (P for trend > 0.05). Results were not substantially different using estimated glomerular filtration rate. LIMITATIONS: Observational study design and indirect measures of kidney function. CONCLUSIONS: Men and women with impaired kidney function are at increased risk of bone loss, even with minimal reduction in kidney function.
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2009
S A Jamal, D Goltzman, D A Hanley, A Papaioannou, J C Prior, R G Josse (2009)  Nitrate use and changes in bone mineral density: the Canadian Multicentre Osteoporosis Study.   Osteoporos Int 20: 5. 737-744 May  
Abstract: Nitrates may have beneficial effects on bone. To determine if nitrates were associated with increased bone mineral density (BMD), we conducted a secondary analysis using data from subjects in a prospective study. Subjects reporting nitrate use had increased BMD compared with non-users, confirming that nitrates have positive BMD effects in women and men. INTRODUCTION: Prior studies suggest positive associations between nitrates and bone. METHODS: We used linear regression models, stratified by gender and adjusted for age, weight, and baseline differences, to determine the association between daily nitrate use and BMD among subjects participating in the Canadian Multicentre Osteoporosis Study. All results are reported as annualised percent change in BMD at the hip and spine among nitrate users compared to non-users. RESULTS: We included 1,419 men (71 reported daily nitrate use) and 2,587 women (97 reported daily nitrate use). Male non-users had decreased hip BMD (-1.3%; 95% confidence interval [95%CI] = -1.6 to -1.1) and increased spine BMD (2.8%; 95%CI = 2.5 to 3.1). Male nitrate users had increased hip BMD (1.4%; 95%CI = 0.1 to 2.8) and spine BMD (4.5%; 95%CI = 3.2 to 5.7). Among women, non-users had decreased hip BMD (-1.9; 95%CI = -2.1 to -1.7) and increased spine BMD (2.1%; 95%CI = 1.9 to 2.4) whilst users had an increase in hip BMD (2.0%; 95%CI = 1.2 to 2.8) and spine BMD (4.1%; 95%CI = 3.4 to 4.9). CONCLUSION: Nitrate use is associated with increased BMD at the hip and spine in men and women.
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L A Langsetmo, S Morin, J B Richards, K S Davison, W P Olszynski, J C Prior, R Josse, D Goltzman (2009)  Effectiveness of antiresorptives for the prevention of nonvertebral low-trauma fractures in a population-based cohort of women.   Osteoporos Int 20: 2. 283-290 Feb  
Abstract: Observational studies are needed to quantify real-life effectiveness of antiresorptive therapy in the prevention of clinical fractures. Antiresorptive therapies were associated with an overall 32% reduction in low-trauma nonvertebral fracture risk among women 50 and older. Effectiveness may be lower among older women and those without risk factors. INTRODUCTION: Randomized controlled trials have shown that antiresorptive therapies reduce the risk of fracture in selected populations, but further study is needed to quantify their real-life effectiveness. The study objective was to determine the association between antiresorptive use and low-trauma nonvertebral fracture in women 50 and older. METHODS: The design was a retrospective nested case-control study (density-based sampling) within the Canadian Multicentre Osteoporosis Study. There were 5,979 eligible women with 453 cases and 1,304 matched controls. RESULTS: The current use of antiresorptives was associated with a decreased risk of fracture with OR = 0.68, 95% CI: 0.52-0.91; where OR is the adjusted odds ratio and CI is the confidence interval. Subgroup analysis yielded OR = 0.61, 95% CI: 0.42-0.89 for ages 50-74; OR = 0.76, 95% CI: 0.50-1.17 for ages 75+; OR = 0.58, 95% CI: 0.40-0.83 for those with a major risk factor; and OR = 0.92; 95% CI: 0.59-1.42 for those without a major risk factor. Major risk factors were prevalent low-trauma fracture, vertebral deformity (grade 2+), and BMD T-score < or = -2.5. CONCLUSIONS: Antiresorptive therapy is associated with a clinically important reduction in low-trauma nonvertebral fracture risk among community-dwelling women aged 50 and older. Antiresorptive therapy may be less effective for women 75 and older and women without major risk factors.
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George Ioannidis, Alexandra Papaioannou, Wilma M Hopman, Noori Akhtar-Danesh, Tassos Anastassiades, Laura Pickard, Courtney C Kennedy, Jerilynn C Prior, Wojciech P Olszynski, Kenneth S Davison, David Goltzman, Lehana Thabane, Amiran Gafni, Emmanuel A Papadimitropoulos, Jacques P Brown, Robert G Josse, David A Hanley, Jonathan D Adachi (2009)  Relation between fractures and mortality: results from the Canadian Multicentre Osteoporosis Study.   CMAJ 181: 5. 265-271 Sep  
Abstract: BACKGROUND: Fractures have largely been assessed by their impact on quality of life or health care costs. We conducted this study to evaluate the relation between fractures and mortality. METHODS: A total of 7753 randomly selected people (2187 men and 5566 women) aged 50 years and older from across Canada participated in a 5-year observational cohort study. Incident fractures were identified on the basis of validated self-report and were classified by type (vertebral, pelvic, forearm or wrist, rib, hip and "other"). We subdivided fracture groups by the year in which the fracture occurred during follow-up; those occurring in the fourth and fifth years were grouped together. We examined the relation between the time of the incident fracture and death. RESULTS: Compared with participants who had no fracture during follow-up, those who had a vertebral fracture in the second year were at increased risk of death (adjusted hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.1-6.6); also at risk were those who had a hip fracture during the first year (adjusted HR 3.2, 95% CI 1.4-7.4). Among women, the risk of death was increased for those with a vertebral fracture during the first year (adjusted HR 3.7, 95% CI 1.1-12.8) or the second year of follow-up (adjusted HR 3.2, 95% CI 1.2-8.1). The risk of death was also increased among women with hip fracture during the first year of follow-up (adjusted HR 3.0, 95% CI 1.0-8.7). INTERPRETATION: Vertebral and hip fractures are associated with an increased risk of death. Interventions that reduce the incidence of these fractures need to be implemented to improve survival.
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A Papaioannou, C C Kennedy, G Ioannidis, A Sawka, W M Hopman, L Pickard, J P Brown, R G Josse, S Kaiser, T Anastassiades, D Goltzman, M Papadimitropoulos, A Tenenhouse, J C Prior, W P Olszynski, J D Adachi (2009)  The impact of incident fractures on health-related quality of life: 5 years of data from the Canadian Multicentre Osteoporosis Study.   Osteoporos Int 20: 5. 703-714 May  
Abstract: Using prospective data from the Canadian Multicentre Osteoporosis Study (CaMos), we compared health utilities index (HUI) scores after 5 years of follow-up among participants (50 years and older) with and without incident clinical fractures. Incident fractures had a negative impact on HUI scores over time. INTRODUCTION: This study examined change in health-related quality of life (HRQL) in those with and without incident clinical fractures as measured by the HUI. METHODS: The study cohort was 4,820 women and 1,783 men (50 years and older) from the CaMos. The HUI was administered at baseline and year 5. Participants were sub-divided into incident fracture groups (hip, rib, spine, forearm, pelvis, other) and were compared with those without these fractures. The effects of both time and fracture type on HUI scores were examined in multivariable regression analyses. RESULTS: Men and women with hip fractures, compared to those without, had lower HUI measures that ranged from -0.05 to -0.25. Both women and men with spine fractures had significant deficits on the pain attributes (-0.07 to -0.12). In women, self-care (-0.06), mobility and ambulation (-0.05) were also negatively impacted. Women with rib fractures had deficits similar to women with spine fractures, and these effects persisted over time. In men, rib fractures did not significantly affect HUI scores. Pelvic and forearm fractures did not substantially influence HUI scores. CONCLUSION: The HUI was a sensitive measure of HRQL change over time. These results will inform economic analyses evaluating osteoporosis therapies.
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Jennifer L Bedford, Jerilynn C Prior, Christine L Hitchcock, Susan I Barr (2009)  Detecting evidence of luteal activity by least-squares quantitative basal temperature analysis against urinary progesterone metabolites and the effect of wake-time variability.   Eur J Obstet Gynecol Reprod Biol 146: 1. 76-80 Sep  
Abstract: OBJECTIVE: To assess computerised least-squares analysis of quantitative basal temperature (LS-BT) against urinary pregnanediol glucuronide (PdG) as an indirect measure of ovulation, and to evaluate the stability of LS-QBT to wake-time variation. STUDY DESIGN: Cross-sectional study of 40 healthy, normal-weight, regularly menstruating women aged 19-34. Participants recorded basal temperature and collected first void urine daily for one complete menstrual cycle. Evidence of luteal activity (ELA), an indirect ovulation indicator, was assessed using Kassam's PdG algorithm, which identifies a sustained 3-day PdG rise, and the LS-QBT algorithm, by determining whether the temperature curve is significantly biphasic. Cycles were classified as ELA(+) or ELA(-). We explored the need to pre-screen for wake-time variations by repeating the analysis using: (A) all recorded temperatures, (B) wake-time adjusted temperatures, (C) temperatures within 2h of average wake-time, and (D) expert reviewed temperatures. RESULTS: Relative to PdG, classification of cycles as ELA(+) was 35 of 36 for LS-QBT methods A and B, 33 of 34 (method C) and 30 of 31 (method D). Classification of cycles as ELA(-) was 1 of 4 (methods A and B) and 0 of 3 (methods C and D). Positive predictive value was 92% for methods A-C and 91% for method D. Negative predictive value was 50% for methods A and B and 0% for methods C and D. Overall accuracy was 90% for methods A and B, 89% for method C and 88% for method D. The day of a significant temperature increase by LS-QBT and the first day of a sustained PdG rise were correlated (r=0.803, 0.741, 0.651, 0.747 for methods A-D, respectively, all p<0.001). CONCLUSION: LS-QBT showed excellent detection of ELA(+) cycles (sensitivity, positive predictive value) but poor detection of ELA(-) cycles (specificity, negative predictive value) relative to urinary PdG. Correlations between the methods and overall accuracy were good and similar for all analyses. Findings suggest that LS-QBT is robust to wake-time variability and that expert interpretation is unnecessary. This method shows promise for use as an epidemiological tool to document cyclic progesterone increase. Further validation relative to daily transvaginal ultrasound is required.
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Peiqi Chen, John H Krege, Jonathan D Adachi, Jerilynn C Prior, Alan Tenenhouse, Jacques P Brown, Emmanuel Papadimitropoulos, Nancy Kreiger, Wojciech P Olszynski, Robert G Josse, David Goltzman (2009)  Vertebral fracture status and the World Health Organization risk factors for predicting osteoporotic fracture risk.   J Bone Miner Res 24: 3. 495-502 Mar  
Abstract: Vertebral fractures are the most common osteoporotic fracture, and patients with prevalent vertebral fractures have a greater risk of future fractures. However, radiographically determined vertebral fractures are not identified as a distinct risk factor in the World Health Organization (WHO) fracture risk assessment tool. The objective of this study was to evaluate and compare potential risk factors including morphometric spine fracture status and the WHO risk factors for predicting 5-yr fracture risk. We hypothesized that spine fracture status provides prognostic information in addition to consideration of the WHO risk factors alone. A randomly selected, population-based community cohort of 2761 noninstitutionalized men and women > or =50 yr of age living within 50 km of one of nine regional centers was enrolled in the Canadian Multicentre Osteoporosis Study (CaMOS), a prospective and longitudinal cohort study following subjects for 5 yr. Prevalent and incident spine fractures were identified from lateral spine radiographs. Incident nonvertebral fragility fractures were determined by an annual, mailed fracture questionnaire with validation, and nonvertebral fragility fracture was defined by investigators as a fracture with minimal trauma. A model considering the WHO risk factors plus spine fracture status provided greater prognostic information regarding future fracture risk than a model considering the WHO risk factors alone. In univariate analyses, age, BMD, and spine fracture status had the highest gradient of risk. A model considering these three risk factors captured almost all of the predictive information provided by a model considering spine fracture status plus the WHO risk factors and provided greater predictive information than a model considering the WHO risk factors alone. The use of spine fracture status along with age and BMD predicted future fracture risk with greater simplicity and higher prognostic accuracy than consideration of the risk factors included in the WHO tool.
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Anne T Harvey, Christine L Hitchcock, Jerilynn C Prior (2009)  Ovulation disturbances and mood across the menstrual cycles of healthy women.   J Psychosom Obstet Gynaecol 30: 4. 207-214 Dec  
Abstract: We examined the cyclicity of negative mood relative to ovulation and ovulation disturbances in Menstrual Cycle Diary(c) data collected daily during a 1-year study of ovulation, exercise, and bone change. A validated quantitative basal temperature-based methodology was used to determine the onset of the luteal phase. 'Feeling depressed', 'feeling anxious', and 'feeling angry/frustrated' were scored on a scale of 0 (absent) to 4 (very intense). Mood scores were examined over two 15-day intervals centered on either ovulation/midpoint, or on the onset of flow. Data were available from 765 cycles of 62 healthy and initially ovulatory women with a mean age of 33.9 +/- 5.4 years. Of 739 cycles that could be classified, 532 (72%) were normally ovulatory, 185 (25%) were ovulatory with a short (<10 day) luteal phase, and 22 (3%) were anovulatory. Minor cyclic mood changes were present in both ovulatory and anovulatory menstrual cycles. In anovulatory cycles, mood tended to be more variable but less negative, with a time course that differed from that in ovulatory cycles. Mood scores did not differ based on luteal phase length or with hormone levels. Patterns and mechanisms of mood change in very symptomatic women appear to be essentially amplifications of normal experiences.
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Claudie Berger, Lisa Langsetmo, Lawrence Joseph, David A Hanley, K Shawn Davison, Robert G Josse, Jerilynn C Prior, Nancy Kreiger, Alan Tenenhouse, David Goltzman (2009)  Association between change in BMD and fragility fracture in women and men.   J Bone Miner Res 24: 2. 361-370 Feb  
Abstract: Our objective was to estimate the relationship between longitudinal change in BMD and fragility fractures. We studied 3635 women and 1417 men 50-85 yr of age in the Canadian Multicentre Osteoporosis Study who had at least two BMD measurements (lumbar spine, femoral neck, total hip, and trochanter) within the first 5 yr of the study and fragility fractures (any, main, forearm/wrist, ribs, hip) within the first 7 yr. Multiple logistic regression was used to model the relationship between baseline BMD, BMD change, and fragility fractures. We found that, among nonusers of antiresorptives, independent of baseline BMD, a decrease of 0.01 g/cm(2)/yr in total hip BMD was associated with an increased risk of fragility fracture with ORs of 1.15 (95% CI: 1.01; 1.32) in women and 1.34 (95% CI: 1.02; 1.78) in men. The risk of fragility fractures in subgroups such as fast losers and those with osteopenia was better estimated by models that included BMD change than by models that included baseline BMD but excluded BMD change. Although the association between baseline BMD and fragility fractures was similar in users and nonusers of antiresorptives, the association was stronger in nonusers compared with users. These results show that BMD change in both men and women is an independent risk factor for fragility fractures and also predicts fracture risk in those with osteopenia. The results suggest that BMD change should be included with other variables in a comprehensive fracture prediction model to capture its contribution to osteoporotic fracture risk.
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Wilma M Hopman, Claudie Berger, Lawrence Joseph, Tanveer Towheed, Jerilynn C Prior, Tassos Anastassiades, Suzette Poliquin, Wei Zhou, Jonathan D Adachi, David A Hanley, Emmanuel A Papadimitropoulos, Alan Tenenhouse (2009)  Health-related quality of life in Canadian adolescents and young adults: normative data using the SF-36.   Can J Public Health 100: 6. 449-452 Nov/Dec  
Abstract: OBJECTIVES: Normative data for the SF-36 measure of health-related quality of life (HRQOL) exist for those over 25 years of age, based on data from the population-based Canadian Multicentre Osteoporosis Study (CaMos). CaMos recently recruited a sample of young Canadians aged between 16 and 24 years. The purpose of this study was to develop normative SF-36 data for this age group. METHODS: After direct standardization to the Canadian population, means, standard deviations (SD), 95% confidence intervals and percentage at floor and ceiling were produced for the eight domain and two summary scores of the SF-36. Domains are scored from 0 (poor) to 100 (excellent). Summary scores are standardized to a mean of 50, with scores over 50 representing better than average and below 50 poorer than average function. Separate analyses were completed for men and women, and for those 16-19 years and 20-24 years. RESULTS: The 1,001 community-based participants consisted of 474 men and 527 women from nine CaMos centres across Canada. Mean Physical Component Summary scores were 53.9 (SD = 6.9) and 53.3 (SD = 5.7) for young men and women, respectively. The equivalent Mental Component Summary scores were 49.3 (SD = 9.7) and 48.8 (SD = 8.9). In general, men scored somewhat higher than women, and younger (16-19 years) women scored higher than older (20-24 years) women, although the differences were small. CONCLUSION: HRQOL is good in this cohort of young Canadians. Both men and women scored somewhat better on physically than mentally oriented domains. In general, Canadian scores were similar to those of the US, while a comparable Swedish sample scored higher than both countries on most domains. Results underscore the importance of taking country, age and gender into consideration when using normative data.
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2008
M Anne Harris, Jerilynn C Prior, Mieke Koehoorn (2008)  Age at menarche in the Canadian population: secular trends and relationship to adulthood BMI.   J Adolesc Health 43: 6. 548-554 Dec  
Abstract: PURPOSE: Studies from around the world indicate a trend toward younger ages of menarche. The extent of this trend in the Canadian population is unknown, and the relationship to later-life health indicators has not yet been fully elucidated. The objective of this study is to estimate the trend in age at menarche (AAM) in the Canadian population and evaluate the relationship between AAM and adult body mass index (BMI). METHODS: Our data source was a nationally representative survey (the Canadian Community Health Survey, 2.2), and analyses included 8080 women, aged 15 and older, who self-reported AAM. Height and weight were measured by the interviewers for the calculation of current BMI. We modeled the secular trend in AAM over time, and the relationship between current BMI and AAM. RESULTS: We found a statistically significant decline in AAM in successive age cohorts, indicating a 0.73-year (8.8-month) decrease in AAM between the oldest and youngest age cohorts in the sample. A 1-year increase in AAM was associated with a decrease in mean BMI of approximately 0.5 kg/m(2), after adjustment for covariates. A current age-AAM interaction term was nonsignificant, indicating that the relationship was stable throughout increasing temporal separation from puberty. CONCLUSION: The observed trend toward earlier menarche could be an indicator of a change in insulin-related metabolism, possibly mediated by behavioral and environmental variables. This study suggests that AAM may be an important clinical and public health indicator of susceptibility to overweight and obesity and attendant morbidity.
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A Papaioannou, C C Kennedy, G Ioannidis, Y Gao, A M Sawka, D Goltzman, A Tenenhouse, L Pickard, W P Olszynski, K S Davison, S Kaiser, R G Josse, N Kreiger, D A Hanley, J C Prior, J P Brown, T Anastassiades, J D Adachi (2008)  The osteoporosis care gap in men with fragility fractures: the Canadian Multicentre Osteoporosis Study.   Osteoporos Int 19: 4. 581-587 Apr  
Abstract: We examined osteoporosis diagnosis/treatment in 2,187 community dwelling men age 50+. After five years in the study, 90% of men with fragility fractures remained undiagnosed and untreated for osteoporosis. The need to treat fragility fractures is well established in guidelines, and these numbers represent an important care gap. INTRODUCTION: Whether physicians in the community are recognizing and appropriately treating osteoporosis and fragility fractures in men remains unknown. We examined the rate of diagnosis and treatment in community dwelling men participating in the Canadian Multicentre Osteoporosis Study (CaMos). METHODS: Between February 1996 and September 2002, 2,187 participants were recruited from nine sites across Canada and prospectively followed. Information on osteoporosis diagnosis, fractures, medications were collected annually by a detailed questionnaire. DXA examination of lumbar spine (L1-4) and hip were conducted at baseline and year five. RESULTS: Diagnosis and treatment in men with clinical fragility fractures was low: at baseline and year five only 2.3% and 10.3% of men with a clinical fracture reported an osteoporosis diagnosis, respectively. At year five, 90% of men with a clinical fragility fracture were untreated. Hip fractures were the most commonly treated (37.5% by year five). A diagnosis of osteoporosis resulted in greater treatment: 67% of participants with diagnosed osteoporosis were treated with a bisphosphonate and 87% were taking calcium and/or vitamin D (year five). CONCLUSIONS: In this population-based study, both a diagnostic and therapeutic gap existed between knowledge and practice related to fragility fractures and osteoporosis in men aged >or=50 years.
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Christine Simonelli, Robert A Adler, Glen M Blake, JoAnn P Caudill, Aliya Khan, Ed Leib, Michael Maricic, Jerilynn C Prior, Sergio Ragi Eis, Cliff Rosen, David L Kendler (2008)  Dual-Energy X-Ray Absorptiometry Technical issues: the 2007 ISCD Official Positions.   J Clin Densitom 11: 1. 109-122 Jan/Mar  
Abstract: At the 2007 Position Development Conference, the Dual-Energy X-ray Absorptiometry Technical Task Force investigated three major areas of bone density testing. Although bone mineral density (BMD) testing in men had previously been reviewed at the 2005 Position Development Conference, we reviewed the most recent data in men to develop appropriate indications for bone density testing in men. We continue to recommend screening at age 70 and discuss the clinical risk factors that may be an appropriate indication for earlier BMD testing. Menopausal transition (perimenopause) was considered an important time to consider BMD evaluation because bone loss may be significant prior to menopause. However, because fracture risk is inherently low in women of this age without other risk factors, screening BMD testing is not appropriate. We discuss the risk factors that are strong indicators of fracture risk that may be increased during the menopause transition. The presence of these risk factors are appropriate indications for BMD testing with applicability of WHO diagnostic categorization. The issue of establishing a high threshold for BMD was investigated thoroughly and the current literature was reviewed. Despite the fact there is agreement that all BMD values greater than T-score -1.0 are not normal, it was felt that because of the paucity of sensitivity data and confounding factors such as high body mass index, an upper threshold could not be established or recommended at this time. This was felt to be an important area for further research.
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2007
Wilma M Hopman, Claudie Berger, Lawrence Joseph, Susan I Barr, Yongjun Gao, Jerilynn C Prior, Suzette Poliquin, Tanveer Towheed, Tassos Anastassiades (2007)  The association between body mass index and health-related quality of life: data from CaMos, a stratified population study.   Qual Life Res 16: 10. 1595-1603 Dec  
Abstract: BACKGROUND: Deviation from normal weight is associated with health risks, but less is known about the association between weight and health-related quality of life (HRQOL). We investigated this in the context of a population-based study, using a standard five-category weight classification system based on body mass index (BMI). METHODS: The Canadian Multicentre Osteoporosis Study is a randomly selected sample of men and women over 25 years of age from nine centres across Canada. Data were obtained by interview, and height and weight were measured and used to calculate BMI. HRQOL was measured using the SF-36. Multivariable linear regression was used to identify the association between BMI category and SF-36 scores after controlling for potential confounders. RESULTS: Complete data were available for 6,302 women and 2,792 men. Mean BMI for every age and gender group exceeded healthy weight guidelines. For women, being underweight, overweight or obese was associated with poorer HRQOL in most SF-36 outcomes while for men, this was associated with poorer HRQOL in some domains and with higher HRQOL in others. CONCLUSIONS: A significant proportion of the population may be putting their health at risk due to excess weight, which may have a substantial negative effect on HRQOL, particularly in women. This underscores the need for continued public health efforts aimed at combating overweight and obesity.
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Wilma M Hopman, Cristine Leroux, Claudie Berger, Lawrence Joseph, Susan I Barr, Jerilynn C Prior, Mark Harrison, Suzette Poliquin, Tanveer Towheed, Tassos Anastassiades, David Goltzman (2007)  Changes in body mass index in Canadians over a five-year period: results of a prospective, population-based study.   BMC Public Health 7: 07  
Abstract: BACKGROUND: The initiation of the Canadian Multicentre Osteoporosis Study in 1996, and subsequent follow-up of the cohort 5 years later, provided longitudinal body mass index (BMI) data for a random sample of Canadians. METHODS: Height and weight were measured at baseline and 5 years and used to calculate BMI and assign one of six weight categories. Multiple imputation was used to adjust for missing weight at year 5. Data were stratified by age and gender. The proportion of participants moving between categories was generated, and multivariable linear regression was used to identify factors associated with weight change. RESULTS: Baseline data were available for 8548 participants, year 5 data for 6721, and year 5 weight was imputed for 1827 (17.6%). Mean BMI for every age and gender group exceeded healthy weight guidelines. Most remained within their BMI classification over 5 years, but when change occurred, BMI category was more likely to increase than decrease. Several sociodemographic, lifestyle and clinical characteristics were associated with change. CONCLUSION: Mean baseline BMI tended to be higher than recommended. Moreover, on average, men under age 45 and women under age 55 were gaining approximately 0.45 kilograms (one pound) per year, which leveled off with increased age and reversed in the oldest age groups. These findings underscore the need for public health efforts aimed at combating obesity.
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Jerilynn C Prior, Jason D Nielsen, Christine L Hitchcock, Lucy A Williams, Yvette M Vigna, Charmaine B Dean (2007)  Medroxyprogesterone and conjugated oestrogen are equivalent for hot flushes: a 1-year randomized double-blind trial following premenopausal ovariectomy.   Clin Sci (Lond) 112: 10. 517-525 May  
Abstract: Oestrogen therapy is the gold standard treatment for hot flushes/night sweats, but it and oestrogen/progestin are not suitable for all women. MPA (medroxyprogesterone acetate) reduces hot flushes, but its effectiveness compared with oestrogen is unknown. In the present study, oral oestrogen [CEE (conjugated equine oestrogen)] and MPA were compared for their effects on hot flushes in a planned analysis of a secondary outcome for a 1-year randomized double-blind parallel group controlled trial in an urban academic medical centre. Participants were healthy menstruating women prior to hysterectomy/ovariectomy for benign disease. A total of 41 women {age, 45 (5) years [value is mean (S.D.)]} were enrolled; 38 women were included in this analysis of daily identical capsules containing CEE (0.6 mg/day) or MPA (10 mg/day). Demographic variables did not differ at baseline. Daily data provided the number of night and day flushes compared by group. The vasomotor symptom day-to-day intensity change was assessed by therapy assignment. Hot flushes/night sweats were well controlled in both groups, one occurred on average every third day and every fourth night. Mean/day daytime occurrences were 0.363 and 0.187 with CEE and MPA respectively, but were not significantly different (P=0.156). Night sweats also did not differ significantly (P=0.766). Therapies were statistically equivalent (within one event/24 h) in the control of vasomotor symptoms. Day-to-day hot flush intensity decreased with MPA and tended to remain stable with CEE (P<0.001). In conclusion, this analysis demonstrates that MPA and CEE are equivalent and effective in the control of the number of hot flushes/night sweats immediately following premenopausal ovariectomy.
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Jerilynn C Prior (2007)  FSH and bone--important physiology or not?   Trends Mol Med 13: 1. 1-3 Jan  
Abstract: For many years, osteoporosis in women was equated with estrogen deficiency. The recent articles by Zaidi and colleagues offer a new challenge to the estrogen-deficiency-osteoporosis hypothesis by showing that follicle-stimulating hormone (FSH) stimulates osteoclastic bone resorption perhaps through tumor necrosis factor-alpha (TNF-alpha). These authors, however, neglected to mention bone abnormalities and high testosterone levels that were previously shown in FSH-receptor knockout and other modified mice. It is also possible that they have overemphasized potential relationships of these new data with human bone loss. Despite these fascinating data, the paradigm of FSH causing hypogonadal bone loss is not yet ready to displace the estrogen-deficiency-osteoporosis paradigm, although that model already faces considerable challenge.
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J Brent Richards, Alexandra Papaioannou, Jonathan D Adachi, Lawrence Joseph, Heather E Whitson, Jerilynn C Prior, David Goltzman (2007)  Effect of selective serotonin reuptake inhibitors on the risk of fracture.   Arch Intern Med 167: 2. 188-194 Jan  
Abstract: BACKGROUND: Depression and osteoporotic fractures are common ailments among elderly persons. Selective serotonin reuptake inhibitors (SSRIs) are frequently used in the treatment of depression in this population, and the association between daily SSRI use and fragility fractures is unclear. Our objective was to examine the effect of daily SSRI use on the risk of incident clinical fragility fracture. METHODS: A population-based, randomly selected, prospective cohort study of 5008 community-dwelling adults 50 years and older, followed up over 5 years for incident fractures. Clinical fragility fractures were classified as minimal trauma fractures that were clinically reported and radiographically confirmed. The risk of fragility fracture associated with daily SSRI use was determined while controlling for relevant covariates. RESULTS: Daily SSRI use was reported by 137 subjects. After adjustment for many potential covariates, daily SSRI use was associated with substantially increased risk of incident clinical fragility fracture (hazard rate, 2.1; 95% confidence interval, 1.3-3.4). Daily SSRI use was also associated with increased odds of falling (odds ratio, 2.2; 95% confidence interval, 1.4-3.5), lower bone mineral density at the hip, and a trend toward lower bone mineral density at the spine. These effects were dose dependent and were similar for those who reported taking SSRIs at baseline and at 5 years' follow-up. CONCLUSIONS: Daily SSRI use in adults 50 years and older remained associated with a 2-fold increased risk of clinical fragility fracture after adjustment for potential covariates. Depression and fragility fractures are common in this age group, and the elevated risk attributed to daily SSRI use may have important public health consequences.
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J Brent Richards, William D Leslie, Lawrence Joseph, Kerry Siminoski, David A Hanley, Jonathan D Adachi, Jacques P Brown, Suzanne Morin, Alexandra Papaioannou, Robert G Josse, Jerilynn C Prior, K Shawn Davison, Alan Tenenhouse, David Goltzman (2007)  Changes to osteoporosis prevalence according to method of risk assessment.   J Bone Miner Res 22: 2. 228-234 Feb  
Abstract: The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk. INTRODUCTION: Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy. We examined how the application of such absolute risk classification systems influences the prevalence of those considered to be at high risk for osteoporotic fracture and compared these systems to one based solely on BMD. MATERIALS AND METHODS: Using 6646 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, randomly selected, population-based cohort, we assessed three different systems for determining prevalence of high risk for osteoporotic fracture: a BMD-based system; a simplified risk factor system incorporating age, sex, BMD, and two clinical risk factors; and a comprehensive system, incorporating age, sex, BMD, and seven clinical risk factors. The 10-year absolute risks of incident fragility fracture were compared across systems using three different high-risk thresholds. RESULTS: The prevalence of a T score < or = -2.5 was 18.8% (95% CI: 17.7-19.9%) in women and 3.9% (95% CI: 3.0-4.7%) in men. Using a 15% 10-year risk of fracture threshold, the prevalence of women at high risk increased to 46.9% (95% CI: 45.4-48.4) and 42.5% (95% CI: 41.1-43.9) when the comprehensive and simplified risk factor classification systems were used, respectively. Using a 25% 10-year absolute risk threshold, the prevalence of high risk was similar to that of the BMD-based system, whereas the 20% threshold gave intermediate rates. All thresholds analyzed resulted in an increased prevalence of older women at high risk for fracture, whereas only the 15% 10-year risk of fracture threshold resulted in an increase in the prevalence of men at high risk. CONCLUSIONS: The application of risk factor-based systems results in an increased prevalence of older women at high risk. The prevalence of individuals at high risk may increase with changes to the methods used to determine those who are eligible for therapy. These data have important implications for the pattern of care and costs of treating osteoporotic fractures.
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2006
Anna M Sawka, Alexandra Papaioannou, Robert G Josse, Timothy M Murray, George Ioannidis, David A Hanley, Jerilynn C Prior, Lehana Thabane, E A Papadimitropoulos, Amiram Gafni, Laura Pickard, Tassos Anastassiades, Susan Kirkland, Jonathan D Adachi, The CaMos Research Group (2006)  What is the number of older Canadians needed to screen by measurement of bone density to detect an undiagnosed case of osteoporosis? a population-based study from CaMos.   J Clin Densitom 9: 4. 413-418 Oct/Dec  
Abstract: Routine bone mineral densitometry (BMD) screening has been recommended for women aged >or=65 yr (Osteoporosis Canada [OC], International Society for Clinical Densitometry [ISCD], Canadian and United States Task Forces on Preventative Healthcare, and National Osteoporosis Foundation) and for men >or=65 yr (OC) or >or=70 yr (ISCD). We estimated the number of older Canadians needed to screen (NNS) by BMD to detect an undiagnosed case of osteoporosis, using prospective, multicenter, population-based data from the Canadian Multicentre Osteoporosis Study (CaMos). We included participants aged >or=65 yr with baseline dual-energy X-ray absorptiometry (DXA) BMDs at the femoral neck and lumbar spine (L1-L4). Osteoporosis was defined by a T-score <or=2.5 at either site. Patients were questioned about a prior diagnosis of osteoporosis. We studied 2699 women and 1032 men aged >or=65 yr. The percentage prevalence and 95% confidence intervals were determined. In individuals aged >or=65 yr, the prevalence of osteoporosis was 25.6% in women (95% confidence interval, 24.0%, 27.3%) and 8.9% in men (7.3%, 10.8%). In 652 men aged >or=70 yr, the prevalence of osteoporosis was 11.3% (9.1%, 14.0%). Of the participants with BMD-defined osteoporosis, 76.6% of woman aged >or=65 yr (73.2%, 79.6%; 516 of 674 women), 93.4% of men aged >or=65 yr (86.4%, 96.9%; 85 of 91), and 93.2% of men >or=70 yr (84.9%, 97.0%; 68 of 73) were not aware of it. Thus, the minimum NNS by BMD testing to detect one previously undiagnosed case of osteoporosis in Canada is: 6 women aged >or=65 yr, 13 men aged >or=65 yr, and 10 men aged >or=70 yr.
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2005
Catherine J Bacon, Jerilynn C Prior, Raja T Abboud, Anthony R H Oldham, Donald C McKenzie (2005)  Changes in pulmonary transfer factor with menstrual cycle phase.   Respir Physiol Neurobiol 146: 2-3. 195-203 Apr  
Abstract: To determine whether lung transfer factor for carbon monoxide (T(L(CO))) alters during menstrual phase and if steroid hormone levels relate to these changes, T(L(CO)) and T(L(CO)) adjusted for both alveolar volume (T(L)/V(A)) and haemoglobin concentration, were measured at five predefined and hormonally confirmed menstrual phases in 13 women. No difference between phases was observed in T(L(CO)) or adjusted values. Moreover, there was no association between the maximal change in oestradiol, progesterone, or oestradiol:progesterone ratio and the change in T(L(CO)) measured at the same time. When the first five chronological measurements, regardless of the menstrual phase at which they were measured, were analysed, T(L(CO)) changed significantly (p<0.05) with a maximal change between the first and fourth test (-2.69+/-2.53, 95% confidence interval). Although these results indicate that the first in a series of T(L(CO)) measurements may be higher, we found neither menstrual cycle phase nor ovarian hormone-related changes in T(L(CO)), and conclude that its adjustment for menstrual phase may not be necessary.
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Jerilynn C Prior (2005)  Ovarian aging and the perimenopausal transition: the paradox of endogenous ovarian hyperstimulation.   Endocrine 26: 3. 297-300 Apr  
Abstract: The purpose of this review is to put into a useful clinical context the changing over time of basic ovarian-pituitary-hypothalamic relationships during perimenopause. "Perimenopause" means changes in ovarian hormones, feedback relationships, and clinical experiences beginning in women ages 35-50 with regular flow and ending 1 yr after the final menstrual flow. A key observation must be explained--estradiol levels are increased in perimenopause. Inhibin B levels are lower and activin may be higher in midlife, menstruating women. These changes probably cause higher follicular phase FSH levels--"endogenous ovarian hyperstimulation" results. The positive estradiol feedback on LH is also disturbed--midcycle LH peaks and mid-luteal slow-frequency, high-amplitude LH pulses are less frequent. In addition to higher levels, estradiol receptors may increase in tissues of symptomatic women. Despite hyperstimulation of follicles, progesterone levels and luteal phase lengths are paradoxically decreased--reasons probably include LH peak disruptions and estrogen-stimulated greater corticotrophin-mediated reproductive suppression. In summary, disturbed feedback relationships causing higher and unpredictable estrogen and lower progesterone levels occur throughout perimenopause, especially during regular cycles. Prospective, population-based research is needed to systematically relate these feedback hormonal changes to clinical characteristics and to allow a diagnosis of perimenopause in regularly cycling midlife women.
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Alexandra Papaioannou, Lawrence Joseph, George Ioannidis, Claudie Berger, Tassos Anastassiades, Jacques P Brown, David A Hanley, Wilma Hopman, Robert G Josse, Susan Kirkland, Timothy M Murray, Wojciech P Olszynski, Laura Pickard, Jerilynn C Prior, Kerry Siminoski, Jonathan D Adachi (2005)  Risk factors associated with incident clinical vertebral and nonvertebral fractures in postmenopausal women: the Canadian Multicentre Osteoporosis Study (CaMos).   Osteoporos Int 16: 5. 568-578 May  
Abstract: Utilizing data from the Canadian Multicentre Osteoporosis Study (CaMos), we examined the association between potential risk factors and incident vertebral and nonvertebral fractures. A total of 5,143 postmenopausal women were enrolled. Information collected during the study included data from the CaMos baseline and annually mailed fracture questionnaires, the Short Form 36 (SF-36), the Health Utilities Index, and physical measurements. Participants were followed for 3 years. Postmenopausal women were classified into four groups according to their incident fracture status since baseline: those without a new fracture; those with a new clinically recognized vertebral fracture; those with an incident nonvertebral fracture at the wrist, hip, humerus, pelvis, or ribs (main nonvertebral fracture group); and those with any new nonvertebral fracture (any-nonvertebral-fracture group). We performed multivariate Cox proportional hazard analysis using all possible risk factors to determine the association between risk factors and the time to the first minimal trauma fracture. Best predictive models were also determined using variables that were included in the full models. The Bayesian information criterion was used for model selection. For all analyses, relative risks and associated 95% confidence intervals were calculated. During the follow-up period, 34, 163, and 280 women developed a vertebral, a main nonvertebral, or any nonvertebral fracture, respectively. The best predictive models indicated that a five point lower quality of life as measured by the SF-36 physical component summary score was associated with relative risks of 1.21 (95% CI, 1.02 to 1.44), 1.17 (95% CI, 1.07 to 1.28), and 1.19 (95% CI, 1.11 to 1.27) for incident vertebral, main nonvertebral, and all nonvertebral fractures, respectively. In addition, for a one standard deviation (SD=0.12) lower femoral neck BMD, the relative risks for incident vertebral, main nonvertebral, and any nonvertebral fractures increased by 2.73 (95% CI, 1.74 to 4.28), 1.39 (95% CI, 1.06 to 1.82), and 1.34 (95% CI, 1.09 to 1.65), respectively. Furthermore, various anthropometric measures, disease conditions, and medications are associated with a new fracture. Identifying postmenopausal women at risk is important given that fracture prevention therapies are now available.
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2004
Christine L Hitchcock, Jerilynn C Prior (2004)  Evidence about extending the duration of oral contraceptive use to suppress menstruation.   Womens Health Issues 14: 6. 201-211 Nov/Dec  
Abstract: INTRODUCTION: For many years, individual women and doctors have experimented with extending the duration of active oral contraceptive (OC) pills between pill-free intervals (long OC) to control menstruation. The U.S. approval of an OC with 84 active days and 7 pill-free days in 2003 has attracted considerable media attention. In this review we consider the published evidence on the effectiveness, side effects, and risks of menstrual suppression with long OC. METHODS: We performed a systematic review of published literature on long OC, up to April 2003. RESULTS: Ten papers were located; two were randomized trials comparing long OC to standard OC; the remaining studies were single-group observational studies. Women on long OC schedules had fewer days of scheduled bleeding during days without pills but more days of unscheduled bleeding and spotting than those on standard OC. These problems were worse for women new to OC and diminished over time. Women on long OC were more likely to discontinue due to poor control of bleeding; women on standard OC were more likely to stop because of problems with headaches. Women on long OC and standard OC both showed increases in physiological factors related to clotting, with a nonsignificant tendency for those on long OC to be more affected. No studies considered the effects of long OC on breast tissue, breast density, endometrial safety, or adolescent maturation and reproductive development. No systematic data were available on the return to reproductive function and fertility after taking long OC. There were no placebo-controlled trials and no information on how long OC compares to normal, unmedicated menstrual cycles. Therefore we believe scientific evidence for safety of long OC use is presently lacking.
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2003
J D Adachi, G Ioannidis, L Pickard, C Berger, J C Prior, L Joseph, D A Hanley, W P Olszynski, T M Murray, T Anastassiades, W Hopman, J P Brown, S Kirkland, C Joyce, A Papaioannou, S Poliquin, A Tenenhouse, E A Papadimitropoulos (2003)  The association between osteoporotic fractures and health-related quality of life as measured by the Health Utilities Index in the Canadian Multicentre Osteoporosis Study (CaMos).   Osteoporos Int 14: 11. 895-904 Nov  
Abstract: Osteoporotic fractures can be a major cause of morbidity. It is important to determine the impact of fractures on health-related quality of life (HRQL). A total of 3,394 women and 1,122 men 50 years of age and older, who were recruited for the Canadian Multicentre Osteoporosis Study (CaMos), participated in this cross-sectional study. Minimal trauma fractures of the hip, pelvis, spine, lower body (included upper and lower leg, knee, ankle, and foot), upper body (included arm, elbow, sternum, shoulder, and clavicle), wrist and hand (included forearm, hand, and finger), and ribs were studied. Participants with subclinical vertebral deformities were also examined. The Health Utilities Index Mark II and III Systems were used to assess HRQL. Past osteoporotic fractures varied in prevalence from 1.2% (pelvis) to 27.8% (lower body) in women and 0.3% (pelvis) to 29.3% (wrist) in men. Multivariate linear regression analyses [parameter estimates and corresponding 95% confidence intervals (CI)] indicated that minimal trauma fractures were negatively associated with HRQL and that this relationship depends on fracture type and gender. The multi-attribute scores for the Mark II system were negatively related to hip (-0.05; 95% CI: -0.09, -0.01), lower body (-0.02; 95% CI: -0.03, -0.000), and subclinical vertebral fractures (-0.02; 95% CI: -0.03, -0.00) for women. The multi-attribute scores for the Mark III system were negatively related to hip (-0.09; 95% CI: -0.14, -0.03) and rib fractures (-0.06; 95% CI: -0.11, -0.00) for women, and rib fractures (-0.06; 95% CI: -0.12, -0.00) for men. In conclusion, this study demonstrates a negative association between osteoporotic fractures and quality of life in both women and men.
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C M Lebrun, M A Petit, D C McKenzie, J E Taunton, J C Prior (2003)  Decreased maximal aerobic capacity with use of a triphasic oral contraceptive in highly active women: a randomised controlled trial.   Br J Sports Med 37: 4. 315-320 Aug  
Abstract: BACKGROUND: Oral contraceptives are commonly used by women athletes. However, their effect on athletic performance is unclear. OBJECTIVES: To examine the effects of a moderate dose, triphasic oral contraceptive on measures of athletic performance in highly trained women athletes. METHODS: This is a double blind, placebo controlled trial in 14 women with ovulatory menstrual cycles and maximal aerobic capacity (VO(2)MAX) >/==" BORDER="0">50 ml/kg/min. Four measures of athletic performance were tested: VO(2)MAX, anaerobic capacity (anaerobic speed test), aerobic endurance (time to fatigue at 90% of VO(2)MAX), and isokinetic strength (Cybex II dynamometer). Height, weight, and six skinfold measurements were also recorded. All these observational tests were completed during both the follicular and mid-luteal phases of an ovulatory menstrual cycle. Cycle phases were confirmed by assaying plasma oestradiol and progesterone. Participants were subsequently randomly assigned to either a tricyclic oral contraceptive or placebo and retested in identical fashion (oral contraceptive phase). RESULTS: Absolute and relative changes in VO(2)MAX from follicular to oral contraceptive phase decreased in the oral contraceptive group by 4.7%, whereas the placebo group showed a slight increase (+1.5%) over the same time period. Two of the women taking oral contraceptive had decreases of 4 and 9 ml/kg/min. In contrast, most women in the placebo group improved or maintained VO(2)MAX. There was also a significant increase in the sum of skinfolds in women taking oral contraceptive compared with those taking placebo (p<0.01). There were no significant changes in other physiological variables (maximum ventilation, heart rate, respiratory exchange ratio, packed cell volume) or measures of performance (anaerobic speed test, aerobic endurance, isokinetic strength) as a function of oral contraceptive treatment. CONCLUSIONS: The decrease in VO(2)MAX that occurs when oral contraceptive is taken may influence elite sporting performance in some women. Further studies are required to determine the mechanisms of this change.
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Brian C Lentle, Jerilynn C Prior (2003)  Osteoporosis: What a clinician expects to learn from a patient's bone density examination.   Radiology 228: 3. 620-628 Sep  
Abstract: Osteoporosis has lately become recognized as an important disease on two accounts. On one hand, demographic change has resulted in a greatly increased and increasing burden of morbidity and mortality due to osteoporotic fracturing. On the other hand, lifestyle changes and preventive measures have become recognized as important factors in prevention of both osteoporosis and osteoporotic fractures, while several effective drug treatments have recently become available to treat osteoporosis by increasing bone density and reducing fracture incidence. Because bone density is, with age, the best predictor of fracture risk, its measurement has become central to the care of those potentially at risk. When a clinician refers a person for a bone density examination, the clinician should be concerned less with an "imaging diagnosis" than with the requirement that the laboratory has procedures in place for rigorous quality assurance and precision measurements, as well as for education of the staff involved. Implementation of these measures and an understanding of their clinical relevance in diagnosis and follow-up, as well as communication with clinicians in this context, are more important than any diagnostic insight that might be provided by "interpreting" a bone density study.
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G E Hale, C L Hitchcock, L A Williams, Y M Vigna, J C Prior (2003)  Cyclicity of breast tenderness and night-time vasomotor symptoms in mid-life women: information collected using the Daily Perimenopause Diary.   Climacteric 6: 2. 128-139 Jun  
Abstract: OBJECTIVE: The purpose was to explore cyclicity of breast tenderness and vasomotor symptoms in menstruating mid-life women using the Daily Perimenopause Diary. METHODS: Untreated mid-life women from a convenience sample completed the Daily Perimenopause Diary for clinical (n = 14) or research (n = 10) assessments. Breast tenderness, sleep disturbance and day and night vasomotor intensity were rated on a 0-4 scale with vasomotor number as a count. Daily oral temperature data were analyzed using the Quantitative Basal Temperature algorithm to assess ovulation and estimate luteal phase length. Analysis of variance tested cyclicity using the mean of three 3-day windows (during flow, at mid-cycle and premenstrually). RESULTS: Ninety-eight complete flow-to-flow diaries (from 24 women, mean age 47 years, cycle length 27 +/- 6.4 (standard deviation) days) were available, with quantitative temperature data for 60 cycles in 16 women. Of assessed cycles, 90% were ovulatory; 25% had luteal phases < 10 days. Breast tenderness was maximal in the premenstrual window overall (p < 0.0001) and in the ovulatory subset. Night sweats were maximal premenstrually (p = 0.0035) except in anovulatory cycles. Daytime flushes were not cyclic (p = 0.1333) except in ovulatory cycles (p = 0.031). CONCLUSION: Daily Perimenopause Diaries from mid-life women show premenstrual increases in breast tenderness and night sweats.
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D A Hanley, J P Brown, A Tenenhouse, W P Olszynski, G Ioannidis, C Berger, J C Prior, L Pickard, T M Murray, T Anastassiades, S Kirkland, C Joyce, L Joseph, A Papaioannou, S A Jackson, S Poliquin, J D Adachi (2003)  Associations among disease conditions, bone mineral density, and prevalent vertebral deformities in men and women 50 years of age and older: cross-sectional results from the Canadian Multicentre Osteoporosis Study.   J Bone Miner Res 18: 4. 784-790 Apr  
Abstract: This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.
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2002
Cheri L Van Patten, Ivo A Olivotto, G Keith Chambers, Karen A Gelmon, T Gregory Hislop, Edith Templeton, Angela Wattie, Jerilynn C Prior (2002)  Effect of soy phytoestrogens on hot flashes in postmenopausal women with breast cancer: a randomized, controlled clinical trial.   J Clin Oncol 20: 6. 1449-1455 Mar  
Abstract: PURPOSE: Vasomotor symptoms, such as hot flashes and night sweats, in breast cancer survivors are often worsened by chemotherapy and tamoxifen, and/or the discontinuation of hormone replacement therapy at diagnosis. This study evaluated the acceptability and effectiveness of a soy beverage containing phytoestrogens as a treatment for hot flashes in postmenopausal women with breast cancer. METHODS: A randomized, placebo-controlled, double-blind clinical trial was conducted in postmenopausal women with moderate hot flashes who were previously treated for early-stage breast cancer. Women were stratified for tamoxifen use and randomized to a soy beverage (n = 59) containing 90 mg of isoflavones or to a placebo rice beverage (n = 64). Women recorded the number and severity of hot flashes daily with a daily menopause diary for 4 weeks at baseline and for 12 weeks while consuming 500 mL of a soy or placebo beverage. RESULTS: There were no significant differences between the soy and placebo groups in the number of hot flashes or hot flash scores. However, presumably because of a strong placebo effect, both groups had significant reductions in hot flashes. Mild gastrointestinal side effects were experienced by both groups but occurred with greater frequency and severity with soy. The mean serum genistein concentration at 6 weeks was significantly higher in women who consumed soy (0.61 +/- 0.43 micromol/L) compared with placebo (0.43 +/- 0.37 micromol/L) (P =.02). Overall acceptability and compliance were high and similar in both groups. CONCLUSION: The soy beverage did not alleviate hot flashes in women with breast cancer any more than did a placebo. Future research into other compounds is recommended to identify safe and effective therapies for hot flashes in breast cancer survivors.
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Jerilynn C Prior (2002)  The ageing female reproductive axis II: ovulatory changes with perimenopause.   Novartis Found Symp 242: 172-86; discussion 186-92  
Abstract: Perimenopause, a complex physiological transition for midlife women, begins with changes in experiences many years before cycles become irregular, oestradiol levels decrease or follicle-stimulating hormone levels increase. Erratic and average higher oestradiol levels as well as shorter luteal phase lengths and lower progesterone levels occur during perimenopause. These ovarian changes may be causally related to lower inhibin production but the dynamic prospective inter-relationships within women are not well documented. This review will first define perimenopause and then explore the limited published data on ovulatory characteristics in perimenopause. In addition, it will report preliminary prospective observational data on menstrual cycles and ovulation in initially ovulatory women followed through the perimenopause. Prospective data suggest that ovulation disturbances begin early in perimenopause and increase with irregular cycles. Combined with higher oestradiol levels they may cause menorrhagia. It is not yet known whether disturbances of ovulation relate to bone loss in perimenopausal, as in premenopausal, women. It is also not known whether progesterone therapy can effectively counteract the end organ (breast, endometrial, brain) effects of higher/erratic oestradiol levels and effectively treat perimenopausal vasomotor and other symptoms.
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Nick D Carter, Karim M Khan, Heather A McKay, Moira A Petit, Constance Waterman, Ari Heinonen, Patti A Janssen, Meghan G Donaldson, Arthur Mallinson, Lenore Riddell, Karen Kruse, Jerilynn C Prior, Leon Flicker (2002)  Community-based exercise program reduces risk factors for falls in 65- to 75-year-old women with osteoporosis: randomized controlled trial.   CMAJ 167: 9. 997-1004 Oct  
Abstract: BACKGROUND: Exercise programs improve balance, strength and agility in elderly people and thus may prevent falls. However, specific exercise programs that might be widely used in the community and that might be "prescribed" by physicians, especially for patients with osteoporosis, have not been evaluated. We conducted a randomized controlled trial of such a program designed specifically for women with osteoporosis. METHODS: We identified women 65 to 75 years of age in whom osteoporosis had been diagnosed by dual-energy X-ray absorptiometry in our hospital between 1996 and 2000 and who were not engaged in regular weekly programs of moderate or hard exercise. Women who agreed to participate were randomly assigned to participate in a twice-weekly exercise class or to not participate in the class. We measured baseline data and, 20 weeks later, changes in static balance (by dynamic posturography), dynamic balance (by a timed figure-eight run) and knee extension strength (by dynamometry). RESULTS: Of 93 women who began the trial, 80 completed it. Before adjustment for covariates, the intervention group tended to have greater, although nonsignificant, improvements in static balance (mean difference 4.8%, 95% confidence interval [CI] -1.3% to 11.0%), dynamic balance (mean difference 3.3%, 95% CI -1.7% to 8.4%) and knee extension strength (mean difference 7.8%, 95% CI -5.4% to 21.0%). Mean crude changes in the static balance score were -0.85 (95% CI -2.91 to 1.21) for the control group and 1.40 (95% CI -0.66 to 3.46) for the intervention group. Mean crude changes in figure-eight velocity (dynamic balance) were 0.08 (95% CI 0.02 to 0.14) m/s for the control group and 0.14 (95% CI 0.08 to 0.20) m/s for the intervention group. For knee extension strength, mean changes were -0.58 (95% CI -3.02 to 1.81) kg/m for the control group and 1.03 (95% CI -1.31 to 3.34) kg/m for the intervention group. After adjustment for age, physical activity and years of estrogen use, the improvement in dynamic balance was 4.9% greater for the intervention group than for the control group (p = 0.044). After adjustment for physical activity, cognitive status and number of fractures ever, the improvement in knee extension strength was 12.8% greater for the intervention group than for the control group (p = 0.047). The intervention group also had a 6.3% greater improvement in static balance after adjustment for rheumatoid arthritis and osteoarthritis, but this difference was not significant (p = 0.06). INTERPRETATION: Relative to controls, participants in the exercise program experienced improvements in dynamic balance and strength, both important determinants of risk for falls, particularly in older women with osteoporosis.
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2001
J A McLean, S I Barr, J C Prior (2001)  Cognitive dietary restraint is associated with higher urinary cortisol excretion in healthy premenopausal women.   Am J Clin Nutr 73: 1. 7-12 Jan  
Abstract: BACKGROUND: Cognitive dietary restraint, assessed by the Three-Factor Eating Questionnaire restraint subscale, is associated with subclinical menstrual cycle disturbances. This association may be mediated by stress-activated cortisol release. OBJECTIVE: We assessed whether 24-h urinary cortisol excretion differs between women with high and low restraint scores. DESIGN: Participants (aged 21.6+/-2.5 y; n = 62) with normal-length menstrual cycles and high (n = 33) or low (n = 29) restraint scores completed a questionnaire describing weight history, dietary practices, and exercise. Cortisol, calcium, and creatinine were measured in urine collected over 24 h on a day when all food and beverages were provided and measured. Previously, 3-d food records and anthropometric measurements were obtained. RESULTS: Age, height, weight, body mass index, and length of menstrual cycle were similar between groups. The reported amount of exercise was higher (3.4+/-1.7 compared with 2.2+/-1.8 h/wk; P<0.05) and energy intakes (assessed from 3-d and 24-h food records) were lower in the high- than in the low-restraint group. Ratios of urinary cortisol (nmol) to creatinine (mmol) were higher in the high-restraint than in the low-restraint group (42.9+/-12.9 compared with 36.3+/-8.9; P<0.05), whereas ratios of urinary calcium (mmol) to creatinine were lower (0.3+/-0.1 compared with 0.4+/-0.2; P<0.05) in the high-restraint group. Urinary cortisol was not associated with exercise, nutrient intakes, or anthropometric measurements. CONCLUSIONS: High dietary restraint scores are associated with urinary cortisol, a biological marker of stress, and high cortisol excretion may affect bone health. Our results suggest that further research is warranted to clarify these associations and to determine whether they persist over time.
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J A McLean, S I Barr, J C Prior (2001)  Dietary restraint, exercise, and bone density in young women: are they related?   Med Sci Sports Exerc 33: 8. 1292-1296 Aug  
Abstract: PURPOSE: Women with high scores for dietary restraint have been found to have higher 24-h urinary cortisol excretion and a higher prevalence of subclinical ovulatory disturbances, both of which may be risk factors for bone loss. The purpose of this study was to explore relationships between dietary restraint and bone health in regularly menstruating young women. METHODS: 62 women (age: 21.7 +/- 2.5 yr) had body composition and total body and lumbar spine bone mineral density (BMD) and content (BMC) assessed using dual-energy x-ray absorptiometry. Dietary restraint was assessed using the restraint subscale from the Three-Factor Eating Questionnaire: 29 women had low restraint (LR; restraint score 0--5), 33 had high restraint (HR; restraint score 13--21). Exercise (h x wk(-1)) was assessed by questionnaire on two occasions. RESULTS: LR and HR women were similar in age and body composition (fat mass = 15.0 +/- 4.7 kg, lean mass = 40.9 +/- 4.9 kg), but HR women exercised more (3.4 +/- 1.7 vs 2.2 +/- 1.8 h x wk(-1), P < 0.05). Exercise was correlated with BMD and BMC, and when it was included as a covariate, total body BMC was significantly lower in HR than LR women. In multiple regression analysis, weekly hours of exercise and restraint score were significant predictors of total body BMD and BMC. CONCLUSION: The observations of this cross-sectional study suggest that high levels of cognitive dietary restraint, or associated factors such as higher cortisol, may attenuate the positive effects of exercise on bone in young women.
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J C Prior, S A Kirkland, L Joseph, N Kreiger, T M Murray, D A Hanley, J D Adachi, Y M Vigna, C Berger, L Blondeau, S A Jackson, A Tenenhouse (2001)  Oral contraceptive use and bone mineral density in premenopausal women: cross-sectional, population-based data from the Canadian Multicentre Osteoporosis Study.   CMAJ 165: 8. 1023-1029 Oct  
Abstract: BACKGROUND: Positive and negative effects on bone mineral density (BMD) have been described as a result of the premenopausal use of oral contraceptives (OCs); increased fracture rates have also been reported. This study assessed the relation between OC use and BMD in a population-based, 9-centre, national sample of women aged 25-45 years. METHODS: Premenopausal women who had been enrolled in the Canadian Multicentre Osteoporosis Study were classified as having ever been OC users (> or = 3 months) or as having never been OC users (0 to < 3 months). Data were obtained through extensive questionnaires and measuring of participants' weight, height and the BMD of lumbar vertebrae and the proximal femur. RESULTS: Of the sample of 524 women, whose mean age was 36.3 (standard deviation [SD] 5.9) years, 454 had used OCs; their mean age when they started using OCs was 19.8 (SD 3.5) years and the mean duration of use was 6.8 (SD 4.8) years. Women who had ever and those who had never used OCs showed no differences in age, age at menarche, parity, current calcium intake, exercise, body mass index (BMI), education, past irregular cycles or amenorrhea. OC users reported more alcohol and cigarette use and more use of medications to create regular cycles. Mean BMD values (adjusted for age, BMI and height) were 0.02-0.04 g/cm2 (that is, 2.3%-3.7%) lower in OC users, and were significantly lower in the spine and trochanter. The BMD of the spine in OC users was 1.03 (SD 0.12) g/cm2 versus 1.07 (SD 0.12) g/cm2 (95% confidence interval [CI] of difference -0.07 to -0.001) in those who had never used OCs. BMD was neither related to the duration of OC use nor to gynecological age at first use. Current and past users had similar BMD values. INTERPRETATION: National, population-based data show lower BMD values for the trochanter and spine in premenopausal women who have used OCs compared with those who have never used OCs.
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J D Adachi, G Loannidis, C Berger, L Joseph, A Papaioannou, L Pickard, E A Papadimitropoulos, W Hopman, S Poliquin, J C Prior, D A Hanley, W P Olszynski, T Anastassiades, J P Brown, T Murray, S A Jackson, A Tenenhouse (2001)  The influence of osteoporotic fractures on health-related quality of life in community-dwelling men and women across Canada.   Osteoporos Int 12: 11. 903-908  
Abstract: Health-related quality of life (HRQL) was examined in relation to prevalent fractures in 4816 community-dwelling Canadian men and women 50 years and older participating in the Canadian Multicentre Osteoporosis Study (CaMos). Fractures were of three categories: clinically recognized main fractures, subclinical vertebral fractures and fractures at other sites. Main fractures were divided and analyzed at the hip, spine, wrist/forearm, pelvis and rib sites. Baseline assessments of anthropometric data, medical history, therapeutic drug use, spinal radiographs and prevalent fractures were obtained from all participants. The SF-36 instrument was used as a tool to measure HRQL. A total of 652 (13.5%) main fractures were reported. Results indicated that hip, spine, wrist/forearm, pelvis and rib fractures had occurred in 78 (1.6%), 40 (0.8%), 390 (8.1%), 19 (0.4%) and 125 (2.6%) individuals, respectively (subjects may have had more than one main fracture). Subjects who had experienced a main prevalent fracture had lower HRQL scores compared with non-fractured participants. The largest differences were observed in the physical functioning (-4.0; 95% confidence intervals (CI): -6.0, -2.0) and role-physical functioning domains (-5.8; 95% CI: -9.5, -2.2). In women, the physical functioning domain was most influenced by hip (-14.9%; 95% CI: -20.9, -9.0) and pelvis (-18.1; 95% CI: -27.6, -8.6) fractures. In men, the role-physical domain was most affected by hip fractures (-35.7; 95% CI: -60.4, -11.1). Subjects who experienced subclinical vertebral fractures had lower HRQL scores than those without prevalent fractures. In conclusion, HRQL was lower in the physical functioning domain in women and the role-physical domain in men who sustained main fractures at the hip. Subclinical vertebral fractures exerted a moderate effect on HRQL.
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N D Carter, K M Khan, M A Petit, A Heinonen, C Waterman, M G Donaldson, P A Janssen, A Mallinson, L Riddell, K Kruse, J C Prior, L Flicker, H A McKay (2001)  Results of a 10 week community based strength and balance training programme to reduce fall risk factors: a randomised controlled trial in 65-75 year old women with osteoporosis.   Br J Sports Med 35: 5. 348-351 Oct  
Abstract: OBJECTIVE:To test the efficacy of a community based 10 week exercise intervention to reduce fall risk factors in women with osteoporosis. METHODS:Static balance was measured by computerised dynamic posturography (Equitest), dynamic balance by timed figure of eight run, and knee extension strength by dynamometry. Subjects were randomised to exercise intervention (twice weekly Osteofit classes for 10 weeks) or control groups. RESULTS:The outcome in 79 participants (39 exercise, 40 control) who were available for measurement 10 weeks after baseline measurement is reported. After confounding factors had been controlled for, the exercise group did not make significant gains compared with their control counterparts, although there were consistent trends toward greater improvement in all three primary outcome measures. Relative to the change in control subjects, the exercise group improved by 2.3% in static balance, 1.9% in dynamic balance, and 13.9% in knee extension strength. CONCLUSIONS:A 10 week community based physical activity intervention did not significantly reduce fall risk factors in women with osteoporosis. However, trends toward improvement in key independent risk factors for falling suggest that a study with greater power may show that these variables can be improved to a level that reaches statistical significance.
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S I Barr, M A Petit, Y M Vigna, J C Prior (2001)  Eating attitudes and habitual calcium intake in peripubertal girls are associated with initial bone mineral content and its change over 2 years.   J Bone Miner Res 16: 5. 940-947 May  
Abstract: This 2-year prospective study examined associations among bone mineral acquisition and physical, maturational, and lifestyle variables during the pubertal transition in healthy girls. Forty-five girls, initially 10.5+/-0.6 years, participated. Body composition and bone mineral content (BMC) at the spine and total body (TB) were assessed at baseline and annually thereafter using dual-energy X-ray absorptiometry (DXA). Nutrient intakes were assessed using 3-day diet records and a calcium food frequency questionnaire (FFQ), physical activity by questionnaire, sexual maturation using Tanner's stages of breast and pubic hair maturation, growth by height and weight, and eating attitudes using the children's Eating Attitudes Test (Children's EAT). Mean children's EAT subscale scores (dieting, oral control [OC], and bulimia) were stable over time. Median split of OC subscale scores was used to form high and low OC groups. Groups had similar body composition, dietary intake, activity, and Tanner stage at baseline and 2 years. Using height, weight, and Tanner breast stage as covariates, girls with low OC scores had greater TB BMC at baseline (1452+/-221 g vs. 1387+/-197 g; p = 0.030) and 2 years (2003+/-323 g vs. 1909+/-299 g; p = 0.049) and greater lumbar spine (LS) BMC at 2 years (45.2+/-8.8 g vs. 41.2+/-9.6 g; p = 0.042). In multiple regression analysis, OC score predicted baseline, 2 years, and 2-year change in TB and spinal BMC, contributing 0.9-7.6% to explained variance. Calcium intake predicted baseline, 2 years, and 2-year change in TB BMC, explaining 1.6-5.3% of variance. We conclude that both OC and habitual calcium intake may influence bone mineral acquisition.
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2000
K J Mather, E G Norman, J C Prior, T G Elliott (2000)  Preserved forearm endothelial responses with acute exposure to progesterone: A randomized cross-over trial of 17-beta estradiol, progesterone, and 17-beta estradiol with progesterone in healthy menopausal women.   J Clin Endocrinol Metab 85: 12. 4644-4649 Dec  
Abstract: Regularly menstruating women are relatively protected from cardiovascular disease. Epidemiological and endothelial function studies attribute this protection to estradiol (E(2)), but both progesterone (P) and E(2) are normally present. A range of vascular effects of added progestins have been described, from neutral to detrimental, but the effects of P per se on endothelial function in humans have not been reported. We therefore investigated the acute effects of E(2), P, and E(2) combined with P, on endothelium-dependent and -independent forearm blood flow responses. Using venous occlusion plethysmography, forearm blood flow (FBF) was measured during acute brachial artery infusions, achieving physiologic levels of 17-beta-E(2), P, and 17-beta-E(2) with P in healthy menopausal women with no cardiovascular disease risk factors. Vehicle or hormones were infused, in random order, on 4 days, 1 week apart. Flow responses were measured during coinfusions of hormone with the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator sodium nitroprusside. Twenty-seven healthy menopausal women were studied, and all had normal baseline endothelial responses. Small ( approximately 15%), statistically nonsignificant increases in endothelium-dependent flow responses were seen after all acute hormone treatments. No impairment in response was seen with P alone or in combination with 17-beta-E(2). In healthy menopausal women without cardiovascular disease risk factors and without baseline defects in endothelial function, acute exposure to physiologic levels of 17-beta-E(2), P, and 17-beta-E(2) with P produced equivalent endothelium-dependent responses. These data suggest that P does not have detrimental vascular effects in humans.
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A Tenenhouse, L Joseph, N Kreiger, S Poliquin, T M Murray, L Blondeau, C Berger, D A Hanley, J C Prior (2000)  Estimation of the prevalence of low bone density in Canadian women and men using a population-specific DXA reference standard: the Canadian Multicentre Osteoporosis Study (CaMos).   Osteoporos Int 11: 10. 897-904  
Abstract: The Canadian Multicentre Osteoporosis Study (CaMos) is a prospective cohort study which will measure the incidence and prevalence of osteoporosis and fractures, and the effect of putative risk factors, in a random sample of 10,061 women and men aged > or = 25 years recruited in approximately equal numbers in nine centers across Canada. In this paper we report the results of studies to establish peak bone mass (PBM) which would be appropriate reference data for use in Canada. These reference data are used to estimate the prevalence of osteoporosis and osteopenia in Canadian women and men aged > or = 50 years. Participants were recruited via randomly selected household telephone listings. Bone mineral density (BMD) of the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry using Hologic QDR 1000 or 2000 or Lunar DPX densitometers. BMD results for lumbar spine and femoral neck were converted to a Hologic base. BMD of the lumbar spine in 578 women and 467 men was constant to age 39 years giving a PBM of 1.042 +/- 0.121 g/cm2 for women and 1.058 +/- 0.127 g/cm2 for men. BMD at the femoral neck declined from age 29 years. The mean femoral neck BMD between 25 and 29 years was taken as PBM and was found to be 0.857 +/- 0.125 g/cm2 for women and 0.910 +/- 0.125 g/cm2 for men. Prevalence of osteoporosis, as defined by WHO criteria, in Canadian women aged > or = 50 years was 12.1% at the lumbar spine and 7.9% at the femoral neck with a combined prevalence of 15.8%. In men it was 2.9% at the lumbar spine and 4.8% at the femoral neck with a combined prevalence of 6.6%.
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H A McKay, M A Petit, R W Schutz, J C Prior, S I Barr, K M Khan (2000)  Augmented trochanteric bone mineral density after modified physical education classes: a randomized school-based exercise intervention study in prepubescent and early pubescent children.   J Pediatr 136: 2. 156-162 Feb  
Abstract: BACKGROUND: Of the few exercise intervention studies focusing on pediatric populations, none have confined the intervention to the scheduled physical education curriculum. OBJECTIVE: To examine the effect of an 8-month school-based jumping program on the change in areal bone mineral density (aBMD), in grams per square centimeter, of healthy third- and fourth-grade children. STUDY DESIGN: Ten elementary schools were randomized to exercise (n = 63) and control groups (n = 81). Exercise groups did 10 tuck jumps 3 times weekly and incorporated jumping, hopping, and skipping into twice weekly physical education classes. Control groups did regular physical education classes. At baseline and after 8 months of intervention, we measured aBMD and lean and fat mass by dual-energy x-ray absorptiometry (Hologic QDR-4500). Calcium intake, physical activity, and maturity were estimated by questionnaire. RESULTS: The exercise group showed significantly greater change in femoral trochanteric aBMD (4.4% vs 3.2%; P <.05). There were no group differences at other sites. Results were similar after controlling for covariates (baseline aBMD change in height, change in lean, calcium, physical activity, sex, and ethnicity) in hierarchical regression. CONCLUSIONS: An easily implemented school-based jumping intervention augments aBMD at the trochanteric region in the prepubertal and early pubertal skeleton.
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1999
M A Petit, J C Prior, S I Barr (1999)  Running and ovulation positively change cancellous bone in premenopausal women.   Med Sci Sports Exerc 31: 6. 780-787 Jun  
Abstract: PURPOSE: Exercise is understood to exert positive effects on bone. However cancellous bone has not been shown to increase with exercise. Previous results of our 1-yr observational prospective study in ovulatory women related 20% of the change in cancellous spinal bone mineral density (BMD), measured by quantitative computed tomography (QCT), to luteal phase length (the time from ovulation to menstruation, LL). METHODS: The 66 women who documented exercise daily included normally active women (N = 23) and those who ran consistently or were increasing running in preparation for a marathon (N = 43). Exercise did not affect BMD change in the women as a whole. We re-evaluated those data to determine whether exercise-related effects on spinal cancellous BMD change in regularly cycling premenopausal women were related to ovulatory characteristics. The potential relationship of exercise to BMD change was reanalyzed by stratifying women into tertiles according to average LL documented by quantitative basal temperature analysis. RESULTS: Repeated-measures ANOVA indicated independent positive effects of both luteal length (P = 0.001) and activity (P = 0.041). The 11 runners with LL > 10.9 d had a nonsignificant 0.5% increase in lumbar BMD while the 15 who averaged short LL (<9.9 d) experienced a significant 3.6% loss. In the runners as a group, however, kilometers run per week was negatively related to BMD change throughout (r = -0.347, P = 0.024). CONCLUSIONS: These data are the first to indicate that, in women with regular cycles, luteal length and exercise independently and positively affect change in spinal cancellous BMD.
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1998
S I Barr, J C Prior, K C Janelle, B C Lentle (1998)  Spinal bone mineral density in premenopausal vegetarian and nonvegetarian women: cross-sectional and prospective comparisons.   J Am Diet Assoc 98: 7. 760-765 Jul  
Abstract: OBJECTIVE: To compare spinal bone mineral density (BMD) and 1-year BMD change between premenopausal vegetarian and nonvegetarian women. DESIGN: Cross-sectional comparison of spinal BMD at baseline and prospective comparison of a subsample. SETTING: A western Canadian metropolitan area. SUBJECTS/SAMPLES: Healthy vegetarian (n = 15 lacto-ovo-vegetarian, n = 8 vegan) and nonvegetarian (n = 22) women aged 20 to 40 years, with regular menstrual cycles and stable body weight completed baseline measurements. Twenty of these women (6 lacto-ovo-vegetarian, 5 vegan, 9 nonvegetarian) participated in repeat measurements at approximately 13 months. STATISTICAL ANALYSES PERFORMED: Descriptive statistics, independent sample and paired t tests, 1-way analysis of variance, correlation analysis, and stepwise multiple regression were used to compare groups and to assess associations with BMD. RESULTS: At baseline, subjects were 27.2 +/- 5.1 years old. Vegetarians had lower body mass index (21.1 +/- 2.3 vs 22.7 +/- 1.9, P < .05) and percent body fat (24.0 +/- 5.5% vs 27.4 +/- 5.1%, P < .05); they also tended to have lower BMD (1.148 +/- 0.111 g/cm2 vs 1.216 +/- 0.132 g/cm2, P = .06), although this was not apparent with weight as a covariate (P = .14). Baseline BMD was predicted by vitamin B-12 intake and total body fat (R2 = .24, P = .001). Participants in the follow-up differed only in their being older than nonparticipants. Over 1 year, mean BMD increased significantly (1.1%): by diet group, nonvegetarians' BMD increased but vegetarians' BMD was unchanged. No other monitored variables were associated with BMD change. APPLICATIONS/CONCLUSIONS: Vegetarian women should be aware of links between low BMD and low body weight/body fat, and should maintain adequate intakes of nutrients believed to affect BMD.
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1997
J C Prior, Y M Vigna, J D Wark, D R Eyre, B C Lentle, D K Li, P R Ebeling, L Atley (1997)  Premenopausal ovariectomy-related bone loss: a randomized, double-blind, one-year trial of conjugated estrogen or medroxyprogesterone acetate.   J Bone Miner Res 12: 11. 1851-1863 Nov  
Abstract: The purpose of this study was to contrast the effects of conventional estrogen treatment with medroxyprogesterone on cancellous and cortical bone change in the first year following premenopausal ovariectomy. This 1-year double-blind randomized therapy trial was stratified by osteoporosis family history and performed in an academic medical center and community hospitals. Premenopausal women 45 +/- 5 years old, postovariectomy for benign diseases were provided 600 mg/day of calcium and randomized to daily therapy with conjugated equine estrogen (CEE, 0.6 mg) or medroxyprogesterone (MPA, 10 mg). The primary outcome variable was spinal quantitative computed tomography (QCT) bone density change over 1 year with additional outcomes of dual-energy X-ray absorptiometry (DXA) of proximal femur (FN), whole body (WB), and spine segment (WBS) and N-telopeptide, bone-specific alkaline phosphatase, and other bone marker, hormonal, and weight changes. Results in the 33 women completing the study, whose initial bone densities were normal (QCT 133 mg/cm3, femoral neck 0.94 g/cm2, whole body DXA 1.13 g/cm2), showed annual QCT loss during CEE therapy of -11.5 mg/cm3 (p < 0.0007) and MPA bone loss of -19.7 mg/cm3 (p < 0.0001). Losses were marginally greater on MPA than CEE (p = 0.04). Extremely high postovariectomy (5 days) and pretreatment resorption markers (> 3 SD above premenopausal normal levels) were significantly related to bone loss. Across the year, resorption decreased during CEE but increased on MPA treatment. Significant DXA bone losses were prevented by CEE treatment (-1.4% FN, -.4% WB, and -1.5% WBS, all NS). However, DXA bone loss was not prevented by MPA treatment (-5% FN, -2.8% WB, and -6.1% WBS, all p < 0.03). Average weight gain was significant (+ 3.2 +/- 4.0 kg) and greater on CEE than MPA (+ 4.7 vs. + 2.0 kg, p = 0.049). In conclusion, CEE therapy did not prevent significant 8% cancellous spinal bone loss in the first year following premenopausal ovariectomy, despite supplementation with 600 mg/day of calcium, good control of vasomotor symptoms, and nearly 5 kg of gain in weight. Significant DXA bone loss, however, was prevented by CEE, but not by MPA therapy. These unexpected results were statistically related to high bone resorption following ovariectomy, which CEE suppressed but MPA did not. Bone formation markers increased during MPA therapy but were unchanged during CEE therapy.
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1996
J C Prior, S I Barr, R Chow, R A Faulkner (1996)  Prevention and management of osteoporosis: consensus statements from the Scientific Advisory Board of the Osteoporosis Society of Canada. 5. Physical activity as therapy for osteoporosis.   CMAJ 155: 7. 940-944 Oct  
Abstract: OBJECTIVE: To examine exercise as a therapy for people with osteoporosis. OPTIONS: Immobilization, standing low-load and high-load physical activities. OUTCOMES: Risk of injury, quality of life, risk of falls and fractures, strength and posture and pain management. EVIDENCE: Relevant epidemiologic studies, clinical trials and reviews were examined, including the large-scale FICSIT trial in the United States, a prospective 4-year study of women enrolled in an exercise program in Toronto and the large-scale Study of Osteoporotic Fractures. VALUES: Minimizing risk of injury and increasing quality of life were given a high value. BENEFITS, HARMS, AND COSTS: Moderate physical activity in people with osteoporosis can reduce the risk of falls and fractures, decrease pain and improve fitness and overall quality of life. It may also stimulate bone gain and decrease bone loss. Its positive effects are an adjunct to other interventions, such as hormonal therapy. It may give patients the confidence to resume regular activity and can provide social interaction and support. During exercise programs, proper nutrition is necessary to prevent excessive weight loss and impaired immune function resulting from inadequate protein, vitamin and mineral intake. RECOMMENDATIONS: Immobilization should be avoided if possible in anyone with osteoporosis or at increased risk for osteoporosis. Regular, moderate physical activity is recommended for those with osteoporosis. Elderly people should be assessed for risk of falling to identify those in greatest need of an exercise program. Community group exercise programs are beneficial. Younger people with osteoporosis also need exercise that will preserve or improve bone mass, muscular strength, endurance and cardiovascular fitness. Weight loss as a result of physical activity should be avoided and adequate intake of protein, vitamins and minerals assured. Because the benefits of physical activity are independent of the effect of other therapies, physical activity is an essential adjunct to appropriate nutrition and other therapies. Validation: These recommendations were developed by the Scientific Advisory Board of the Osteoporosis Society of Canada at its 1995 Consensus Conference. They are in agreement with the position taken on osteoporosis and exercise by the United States Center for Disease Control and Prevention and the American College of Sports Medicine. SPONSORS: Sponsors of the 1995 conference included the Dairy Farmers of Canada, Eli Lilly Canada, Inc., Hoffmann-La Roche Canada Ltd., Merck Frosst Canada Inc. and Procter & Gamble Pharmaceuticals Canada Inc.
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J C Prior, Y M Vigna, S I Barr, S Kennedy, M Schulzer, D K Li (1996)  Ovulatory premenopausal women lose cancellous spinal bone: a five year prospective study.   Bone 18: 3. 261-267 Mar  
Abstract: Healthy premenopausal women with regular cycles are believed to be increasing or maintaining bone density. However, few studies have prospectively documented spinal cancellous bone, the bone that changes rapidly in response to reproductive hormones, in this population. Furthermore, our previous one-year study documented that 24% of the one-year bone change by quantitative computed tomography (QCT) was related to subclinical ovulatory disturbances (short luteal phase and non-ovulation) in the presence of regular menstrual cycles. The purpose of this study was to document the cancellous bone change over five years in this initially ovulatory, premenopausal cohort of 66 healthy women. Thirty-seven women, who continued to be premenopausal and have regular cycles, completed this five-year study. Those enrolled differed only by being older and weighing less than those who could not be contacted (n = 19) or who declined to participate (n = 10). Documentation of current ovulatory characteristics was obtained for at least three cycles in 27 women. At the five-year assessment, the volunteers were 40.6 (range 26-47) years old, weighed 58.5 (41-77) kg, and were 160.9 (149-174) cm in height. All were premenopausal, healthy, nonsmokers with regular menstrual cycles (mean 27.7, range 24-33 days). Six women with intervening events (such as pregnancy or use of oral contraceptives) had interval (12 to 60 months) QCT changes similar to the remaining 31 (-7.98 vs. -4.92 mg/cm, p = 0.1, respectively). Mean five-year QCT was 143.0 +/- 20.2 mg/cm, whereas the initial mean value was 151.9 +/- 20.1 mg/cm. Significant QCT loss over five years (-8.9 +/- 6.2 mg/cm) (95% Cl -6.9 to -11.0) correlated with QCT change in the first year (r = 0.629, p < 0.001). First-year change was not related to the subsequent four-year interval change (r = -0.056, p = 0.74), however. Five-year QCT change was not related to age, weight, osteoporosis family history, estimated calcium intake, or exercise, but did correlate with year one luteal index (luteal/cycle length) (r = 0.339, p = 0.043). Significant cancellous spinal bone loss occurs in healthy, ovulatory premenopausal women, and is influenced by subclinical disturbances of ovulation.
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1995
C M Lebrun, D C McKenzie, J C Prior, J E Taunton (1995)  Effects of menstrual cycle phase on athletic performance.   Med Sci Sports Exerc 27: 3. 437-444 Mar  
Abstract: The purpose of this study was to examine the effects of menstrual cycle phase on four selected indices of athletic performance: aerobic capacity, anaerobic capacity, isokinetic strength, and high intensity endurance. Sixteen eumenorrheic women (VO2max > or = 50 ml.kg-1.min-1) were tested during the early follicular (F) and midluteal (L) phases of the menstrual cycle. Cycle phases were confirmed by serum estradiol and progesterone assays. No significant differences were observed between F and L tests in weight, percent body fat, sum of skinfolds, hemoglobin concentration, hematocrit, maximum heart rate, maximum minute ventilation, maximum respiratory exchange ratio, anaerobic performance, endurance time to fatigue (at 90% of VO2max), or isokinetic strength of knee flexion and extension. Both absolute and relative VO2max, however, were slightly lower in L than in F (F = 3.19 +/- 0.09.min-1, L = 3.13 +/- 0.08.min-1, P = 0.04; and F = 53.7 +/- 0.9 ml.kg-1.min-1, L = 52.8 +/- 0.8 ml.kg-1.min-1, P = 0.06). These results suggest that the cyclic increases in endogenous female steroid hormones of an ovulatory menstrual cycle may have a slight, deleterious influence on aerobic capacity, with potential implications for individual athletes. Nevertheless, the cycle phase did not impact significantly on the majority of the other performance tests and cardiorespiratory variables measured in this study.
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S I Barr, K C Janelle, J C Prior (1995)  Energy intakes are higher during the luteal phase of ovulatory menstrual cycles.   Am J Clin Nutr 61: 1. 39-43 Jan  
Abstract: We compared energy and macronutrient intakes across the menstrual cycle in participants (n = 42) in a study that assessed the frequency of ovulatory disturbances in regularly cycling vegetarians and nonvegetarians. Women kept daily basal body temperature records for six consecutive menstrual cycles and provided 3-d diet records near the beginning, middle, and end of different cycles. On completion of the study, temperature records were quantitatively analyzed to determine whether cycles were ovulatory, and if so, the date the luteal phase began. Diet records kept near the beginning and end of cycles were matched with temperature analysis results, and women were grouped according to whether the end-of-cycle record was kept during the luteal phase of an ovulatory cycle (group 1, n = 29), or during an anovulatory cycle or before luteal phase onset of a short luteal phase cycle (group 2, n = 13). Group 1 had higher energy intakes during the luteal than during the follicular phase (9.27 +/- 2.69 vs 8.01 +/- 2.36 MJ/d, P < 0.0001), whereas intakes of group 2 did not differ across the cycle (7.91 +/- 2.18 vs 8.20 +/- 1.48 MJ/d, NS). Both groups' macronutrient intakes were similar in records kept near the beginning and end of cycles. Documentation of ovulation is necessary in studies assessing premenopausal women's energy intakes.
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J C Prior, D W McKay, Y M Vigna, S I Barr (1995)  Medroxyprogesterone increases basal temperature: a placebo-controlled crossover trial in postmenopausal women.   Fertil Steril 63: 6. 1222-1226 Jun  
Abstract: OBJECTIVE: To assess whether temperature is increased by medroxyprogesterone (MPA) and thus whether basal temperature records could be used to determine ovulation during cyclic MPA therapy. DESIGN: A 2-month double-blind placebo-controlled crossover trial in which oral basal temperature was measured daily. SETTING: Normal human volunteers in an academic medical environment. SUBJECTS: Eleven postmenopausal women not taking gonadal hormones. INTERVENTION: Medroxyprogesterone acetate (10 mg/d) or placebo, calendar days 16 to 25, with crossover. MAIN OUTCOME MEASURES: Comparison of mean temperature days 17 to 26 during MPA versus placebo; comparison of differences between temperatures days 7 to 16 and 17 to 26 in MPA versus placebo months; and analysis for a significant monthly thermal shift. RESULTS: The mean temperatures during MPA treatment averaged 0.27 degrees C higher than during the placebo phase and showed a significant change from pretreatment to "treatment" phases during MPA but not during placebo cycles. Eight of the MPA and one of the placebo cycles showed a shift from lower to higher temperatures days 16 to 25. CONCLUSIONS: Medroxyprogesterone acetate has a physiological progesterone-like thermal effect. Therefore basal temperature data cannot reliably indicate ovulation during cyclic MPA administration.
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1994
J C Prior, N Alojado, D W McKay, Y M Vigna (1994)  No adverse effects of medroxyprogesterone treatment without estrogen in postmenopausal women: double-blind, placebo-controlled, crossover trial.   Obstet Gynecol 83: 1. 24-28 Jan  
Abstract: OBJECTIVE: To determine whether cyclic medroxyprogesterone treatment given without estrogen causes adverse symptoms in postmenopausal women. METHODS: This was a placebo-controlled, double-blind, crossover trial of 10 days/month of medroxyprogesterone and placebo treatments given during 2 consecutive months in random order. Participants recorded their physiologic and emotional experiences on a 0-4 scale using a daily diary form. Eleven postmenopausal women aged 43-63 completed the study. The subjects were not taking hormones. Height, weight, and serum estradiol concentration were measured once. In each woman, the sum of scores for the 10 days of medroxyprogesterone was compared to the sum of scores for the 10 days of placebo using nonparametric tests. RESULTS: No significant differences in scores were found between the 10 days on medroxyprogesterone and the 10 days on placebo. The median and range for the composite scores for premenstrual-like symptoms were 26 (20-67) during medroxyprogesterone and 25 (19-40) during placebo (P = .39). CONCLUSIONS: Medroxyprogesterone given alone does not cause adverse symptoms in postmenopausal women. Therefore, medroxyprogesterone therapy, by itself, cannot explain the side effects reported by postmenopausal women taking combined hormones.
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V H Livingstone, P W Gout, S D Crickmer, K Fox, J C Prior (1994)  Serum lactogens possessed normal bioactivity in patients with lactation insufficiency.   Clin Endocrinol (Oxf) 41: 2. 193-198 Aug  
Abstract: OBJECTIVE: Insufficient breast milk is the most common reason for premature termination of breast-feeding. The causes of lactation insufficiency are usually multifactorial; in a small percentage of cases it is due to primary lactation failure of unknown origin. The aim of this study was to investigate whether lactation insufficiency of unknown origin could be caused by serum lactogens that had reduced biological activity. DESIGN: Women with lactation insufficiency of unknown origin and normal lactating controls were subjected to a standardized breast-feeding test for assessment of milk production. Thirty minutes later, serum samples were obtained for determination of total lactogen bioactivity, using an in-vitro bioassay, and levels of prolactin (PRL) and growth hormone (GH) using radioimmunoassay (RIA). PATIENTS: Twelve lactating mothers with a clinical diagnosis of lactation insufficiency of unknown origin were compared with 12 matched mothers with normal lactation. MEASUREMENTS: The Nb2 lymphoma cell bioassay was used to measure total lactogen bioactivity in sera. Conventional RIA kits were used to estimate serum PRL and GH concentrations. RESULTS: Mean milk yield on standardized test feed was 21.6 ml for patients and 146.5 ml for controls. In both patient and control groups the total serum lactogen bioactivity ranged from about 150 to 5000 mIU/l, while the serum RIA (PRL+GH) levels ranged from about 350 to over 7000 mIU/l. There was no evidence of lactogens with reduced bioactivity in the patients' sera. CONCLUSION: Lactation insufficiency in the women studied cannot be explained by serum lactogens that possess unusually low bioactivity.
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S I Barr, K C Janelle, J C Prior (1994)  Vegetarian vs nonvegetarian diets, dietary restraint, and subclinical ovulatory disturbances: prospective 6-mo study.   Am J Clin Nutr 60: 6. 887-894 Dec  
Abstract: Ovulatory function was prospectively assessed over 6 mo in 23 vegetarians and 22 nonvegetarians with clinically normal menstrual cycles. Subjects were 20-40 y of age, of stable weight (body mass index, in kg/m2, of 18-25), on current diets for > or = 2 y, and not using oral contraceptives. Quantitative analysis of basal body temperature records classified cycles as normally ovulatory, short luteal phase (< 10 d), or anovulatory. Subjects completed the Three-Factor Eating Questionnaire (subjects completed the Three-Factor Eating Questionnaire (subscales for restraint, hunger, and disinhibition) and kept three 3-d food records. Vegetarians had lower BMIs (21.1 +/- 2.3 vs 22.7 +/- 1.9, P < 0.05), percentage body fat (24.0 +/- 5.5% vs 27.4 +/- 5.1%, P < 0.05), and restraint scores (6.4 +/- 4.4 vs 9.5 +/- 3.7, P < 0.05). Mean cycle lengths were similar, but vegetarians had longer luteal phase lengths (11.2 +/- 2.6 vs 9.1 +/- 3.8 d, P < 0.05). Cycle types also differed (chi 2 = 9.64, P < 0.01): vegetarians had fewer anovulatory cycles (4.6% vs 15.1% of cycles). Compared with those with restraint scores below the median, highly restrained women had fewer ovulatory cycles (3.6 +/- 2.3 vs 5.0 +/- 1.4, P < 0.05) and shorter mean luteal phase lengths (7.4 +/- 4.1 vs 10.7 +/- 3.1 d, P < 0.05). We conclude that ovulatory disturbances and restrained eating are less common among vegetarians, and that restraint influences ovulatory function.
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J C Prior, Y M Vigna, S I Barr, C Rexworthy, B C Lentle (1994)  Cyclic medroxyprogesterone treatment increases bone density: a controlled trial in active women with menstrual cycle disturbances.   Am J Med 96: 6. 521-530 Jun  
Abstract: OBJECTIVE: Bone loss occurs in young women who experience amenorrhea or ovulatory disturbances. The purpose of this study was to determine whether bone loss could be prevented by simulating a more normal hormonal pattern, using treatment with cyclic medroxyprogesterone, with or without calcium supplementation, in physically active women with disturbed menstruation. DESIGN: This study was a 1-year randomized, double-blind, placebo-controlled trial. Women who were stratified by menstrual cycle disturbance were randomized into four groups. The outcome variable was the change in spinal bone density measured by dual energy techniques. SETTING: A large metropolitan area. PARTICIPANTS: Sixty-one healthy, normal-weight physically active premenopausal women aged 21 to 45 years who experienced amenorrhea, oligomenorrhea, anovulation, or short luteal phase cycles completed the study. INTERVENTION: Therapies were cyclic medroxyprogesterone (10 mg/day for 10 days per month) and calcium carbonate (1,000 mg/day of calcium) in four groups: (A) (n = 16) cyclic medroxyprogesterone plus calcium carbonate; (B) (n = 16) cyclic medroxyprogesterone with calcium placebo; (C) (n = 15) placebo medroxyprogesterone with active calcium; or (D) (n = 14) both medroxyprogesterone and calcium placebos. RESULTS: The initial bone density (mean = 1.12 g/cm2) did not differ by group (P = 0.85). The 1-year bone density change was strongly related to treatment with medroxyprogesterone (P = 0.0001) and weakly to calcium (P = 0.072) treatment. Bone density increased significantly (+1.7% +/- 0.5%, +/- SEM, P = 0.004) in the medroxyprogesterone-treated groups (A and B), did not change in the calcium-treated group (C) (-0.7% +/- 0.6%, P = 0.28), and decreased on both placebos (D) (-2.0% +/- 0.6%, P = 0.005). CONCLUSIONS: Cyclic medroxyprogesterone increased spinal bone density in physically active women experiencing amenorrhea or ovulatory disturbances. POTENTIAL CLINICAL SIGNIFICANCE: Amenorrhea, oligomenorrhea, anovulation, and short luteal phase cycles are common in premenopausal women and associated with spinal bone loss occurring at a stage of life when bone density would normally be stable or increasing. This controlled trial shows a significant gain in bone in women in the cyclic medroxyprogesterone intervention group, whereas those subjects in the placebo group lost bone. Calcium supplementation appeared to be helpful but did not reach statistical significance. The implications of these findings for the prevention of osteoporosis warrant further investigation.
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S I Barr, J C Prior, Y M Vigna (1994)  Restrained eating and ovulatory disturbances: possible implications for bone health.   Am J Clin Nutr 59: 1. 92-97 Jan  
Abstract: We assessed the relationship between dietary restraint and menstrual cycle characteristics in 27 ovulatory women, previous participants in a longitudinal study of spinal cancellous bone mineral density (BMD). Subjects completed the restraint scale of the Three Factor Eating Questionnaire, recorded basal temperature and exercise for at least three menstrual cycles, and completed a 3-d food record. Cycle lengths of women in the upper and lower tertiles of scores for restraint were similar [27.8 +/- 1.0 (mean +/- SE) vs 27.6 +/- 0.8 d], but luteal phase length was shorter in the former group (8.6 +/- 0.9 vs 10.8 +/- 0.5 d, P < 0.05). Age, body mass index, percent body fat, waist-hip ratio, reported energy intake, and activity were similar between groups. Because the previous longitudinal study found associations between ovulatory disturbances and bone loss, we assessed spinal BMD using dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT). BMD of women in upper and lower restraint tertiles, respectively, did not differ: DXA, 1.15 +/- 0.05 vs 1.20 +/- 0.06 g/cm2; and QCT, 140 +/- 7 vs 133 +/- 7 mg/cm3. Additional prospective studies, however, appear warranted. In conclusion, this study's results provide evidence that high dietary restraint is associated with a shortened luteal phase length.
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1993
1992
J C Prior, Y M Vigna, D W McKay (1992)  Reproduction for the athletic woman. New understandings of physiology and management.   Sports Med 14: 3. 190-199 Sep  
Abstract: A physically active and athletic lifestyle is not only a healthy but a fulfilling choice for women. Although there is extensive literature on 'athletic amenorrhoea' which implies that exercise causes loss of the menstrual cycle, there is inadequate scientific evidence for a causal relationship. The reproductive system adapts to environmental, nutritional, emotional and physical stressors or 'threats' by downward adjustment towards the premenarcheal pattern. The hormonal milieu of this adaptation is low gonadal steroid and high glucocorticoid levels which synergistically increase the risk for a negative bone balance. Athletic women may become amenorrhoeic if reproductive immaturity, emotional stress and undernutrition coexist with increasing exercise loads. Treatment for athletic women with menstrual cycle changes requires that hypothalamic stressors be identified and decreased. In addition, as progesterone deficiency (from disorders of ovulation, whether flow is regular or absent) is the most prevalent menstrual cycle change, treatment with medroxyprogesterone on days 16 to 25 of their cycle will not only provide regular flow (if estrogen levels are sufficient) but will also promote increased bone density.
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1991
1990
J C Prior, Y M Vigna, M T Schechter, A E Burgess (1990)  Spinal bone loss and ovulatory disturbances.   N Engl J Med 323: 18. 1221-1227 Nov  
Abstract: BACKGROUND: Osteoporosis develops in women with estrogen deficiency and amenorrhea who lose bone at an accelerated rate. It is not known to what extent bone loss differs between ovulatory women with regular menstrual cycles who are training intensely and those who are sedentary. METHODS: We measured the density of cancellous spinal bone from the 12th thoracic vertebra to the 3rd lumbar vertebra by quantitative computed tomography on two occasions one year apart in 66 premenopausal women 21 to 42 years of age. All the women had two consecutive ovulatory cycles immediately before entering the study. Twenty-one women were training for a marathon, 22 ran regularly but less intensively, and 23 had normal levels of activity. The lengths of the women's menstrual cycles and luteal phases, diet, exercise levels, and hormonal levels were also determined. We defined ovulatory disturbances as anovulatory cycles and cycles with short luteal phases. RESULTS: The mean (+/- SD) spinal bone density in the 66 women decreased 3.0 +/- 4.8 mg per cubic centimeter per year (2.0 percent per year) (P less than 0.001). Amenorrhea did not develop in any woman during the year of observation (only 2.7 percent of the cycles were greater than 36 days long). Ovulatory disturbances occurred in 29 percent of all cycles, however. Bone loss was strongly associated with these disturbances (r = 0.54, 24 percent of the variance). The 13 women who had anovulatory cycles lost bone mineral at a rate of 6.4 +/- 3.8 mg per cubic centimeter per year (4.2 percent per year). The women training for a marathon had menstrual cycles similar to those of the women in the other two groups. CONCLUSION: Decreases in spinal bone density among women with differing exercise habits correlated with asymptomatic disturbances of ovulation (without amenorrhea) and not with physical activity.
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J C Prior, Y M Vigna, M Schulzer, J E Hall, A Bonen (1990)  Determination of luteal phase length by quantitative basal temperature methods: validation against the midcycle LH peak.   Clin Invest Med 13: 3. 123-131 Jun  
Abstract: Basal temperature data are known to provide unreliable assessments of luteal phase length when they are evaluated by qualitative, visual-pattern methods. This study of 24 cycles in 24 women compared the serum LH peak day with the luteal phase onset day determined by three quantitative basal temperature methods: a) a new computerized least mean square method developed by the authors; b) the mean temperature method reported by Vollman; and c) a computerized version of the World Health Organization cumulative sum method of Royston. The luteal phase onset day determined by the three quantitative basal temperature methods, (a, b, and c) correlated well with the midcycle LH peak (r = 0.879, 0.891, and 0.791, respectively, all p less than 0.001). The cumulative sum method, however, was only able to analyze 19/24 cycles. The mean delay between the LH peak day and the luteal phase onset day determined by thermal shift was 2.4 +/- 1.5, 2.7 +/- 1.4, and 4.1 +/- 2.0 d (mean +/- SD), respectively. The mean temperature method, but not the other two methods, showed an increasing delay between the LH peak day and the thermal shift day with longer follicular phase lengths. Rectal and oral temperature data from the same cycle give identical luteal onset days when analyzed by the least mean square and mean temperature methods, but discrepant days by the cumulative sum analysis. The least mean square technique is a reliable and precise method for population documentation of luteal phase lengths.
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J C Prior (1990)  Progesterone as a bone-trophic hormone.   Endocr Rev 11: 2. 386-398 May  
Abstract: Experimental, epidemiological, and clinical data indicate that progesterone is active in bone metabolism. Progesterone appears to act directly on bone by engaging an osteoblast receptor or indirectly through competition for a glucocorticoid osteoblast receptor. Progesterone seems to promote bone formation and/or increase bone turnover. It is possible, through estrogen-stimulated increased progesterone binding to the osteoblast receptor, that progesterone plays a role in the coupling of bone resorption with bone formation. A model of the interdependent actions of progesterone and estrogen on appropriately-"ready" cells in each bone multicellular unit can be tied into the integrated secretions of these hormones within the ovulatory cycle. Figure 5 is an illustration of this concept. It shows the phases of the bone remodeling cycle in parallel with temporal changes in gonadal steroids across a stylized ovulatory cycle. Increasing estrogen production before ovulation may reverse the resorption occurring in a "sensitive" bone multicellular unit while gonadal steroid levels are low at the time of menstrual flow. The bone remodeling unit would then be ready to begin a phase of formation as progesterone levels peaked in the midluteal phase. From this perspective, the normal ovulatory cycle looks like a natural bone-activating, coherence cycle. Critical analysis of the reviewed data indicate that progesterone meets the necessary criteria to play a causal role in mineral metabolism. This review provides the preliminary basis for further molecular, genetic, experimental, and clinical investigation of the role(s) of progesterone in bone remodeling. Much further data are needed about the interrelationships between gonadal steroids and the "life cycle" of bone. Feldman et al., however, may have been prophetic when he commented; "If this anti-glucocorticoid effect of progesterone also holds true in bone, then postmenopausal osteoporosis may be, in part, a progesterone deficiency disease."
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1989
J C Prior, Y M Vigna, D Watson (1989)  Spironolactone with physiological female steroids for presurgical therapy of male-to-female transsexualism.   Arch Sex Behav 18: 1. 49-57 Feb  
Abstract: The clinical and hormonal response to 12-month therapy with the antiandrogen, spironolactone, in conjunction with near-physiologic doses of female gonadal steroids in 50 transsexual males, is presented. An unselected referred series of 61 men with the psychiatric diagnosis of transsexualism was treated; 10 subjects who had received previous gonadal surgery and 1 man with Klinefelter's syndrome were excluded. Twenty-seven conventionally treated (CT; high-dose estrogen), age 34.4 +/- 10.5 years, mean +/- SD, and 23 untreated patients (SPS), age 30.7 +/- 6.2 years, were studied. Following the initial visit, all 50 were begun on spironolactone and low-dose female hormone therapy. Despite high-dose estrogen treatment for more than 2 years, the mean testosterone (T) level for the CT group was not in the female range (169 +/- 193 ng/dl; normal 20-80). Spironolactone, in doses of 200-600 mg/day, lowered T to the female range in both groups after 12 months (CT 87 +/- 111 and SPS 49 +/- 41 ng/dl). This was achieved in the CT group despite decreases in estrogen dose and discontinuation of parenteral therapy. SPS subjects experienced significant decreases in plasma T (642 +/- 236 to 49 +/- 41 ng/dl, p less than 0.001). Systolic blood pressure dropped (128 +/- 14 to 121 +/- 14 mm Hg, p less than 0.05). The clinical response, including decreased male pattern hair, breast development, feminization, and lack of erections was excellent in most subjects.
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1988
J Chapitis, D H Riddick, L M Betz, J R Brumsted, M Gibson, J C Prior, P W Gout (1988)  Physicochemical characterization and functional activity of fibroid prolactin produced in cell culture.   Am J Obstet Gynecol 158: 4. 846-853 Apr  
Abstract: Evidence from our laboratory with the use of cultured (primary and passaged) cells has extended our initial observation that human uterine fibroid is an extrapituitary source of prolactin. Fibroid prolactin antigen in conditioned medium reacted specifically in radioimmunoassay for human pituitary prolactin. Control experiments demonstrated that the radioimmunoassay results were not spurious due to degradation of tracer 125I-labeled prolactin. Immunoparallel dilution curves indicated antigenic relatedness of pituitary and fibroid prolactin. In a calibrated Sephadex G-100 column, fibroid prolactin eluted in the same region (20.3 to 20.9 kd) as purified pituitary prolactin. Glycosylated prolactin, detected by concanavalin A affinity column chromatography, appeared to constitute only a small percentage of fibroid prolactin made in culture. The ratio of fibroid prolactin bioactivity (lactogen Nb2 lymphoma bioassay) to antigen (radioimmunoassay) was 0.77. These data indicate that human uterine fibroid tissue produces a molecule similar to or, perhaps, identical with pituitary prolactin.
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1987
J C Prior (1987)  Physical exercise and the neuroendocrine control of reproduction.   Baillieres Clin Endocrinol Metab 1: 2. 299-317 May  
Abstract: Reproductive change during conditioning exercise (physical training provides a model of hypothalamic adaptation to alterations in the external and internal environment. Parallels exist between the reproductive changes with exercise and those occurring with physical illness, undernutrition and psychological trauma. Although menstrual cyclicity may be disrupted in younger women, luteal phase shortening, anovulation and decreased premenstrual symptoms within normal ovulatory cycles are the most frequent observations noted. Baseline LH, prolactin and oestradiol tend to be lower, and other hormones unchanged, in trained women. Testosterone may be decreased within the normal range in men. Recent evidence shows that LH pulse frequency, amplitude and area under the LH curve are decreased in both female and male runners. Interrelationships between increases in central dopamine, endorphin and probably some hypothalamic message(s) relating to nutritional state appear to modulate these reproductive changes. The clinical and therapeutic response to reproductive alterations in the context of exercise differs when these are seen as adaptive and not as disease processes (Prior and Vigna, 1985b).
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J C Prior, T A Cox, D Fairholm, E Kostashuk, R Nugent (1987)  Testosterone-related exacerbation of a prolactin-producing macroadenoma: possible role for estrogen.   J Clin Endocrinol Metab 64: 2. 391-394 Feb  
Abstract: Men with PRL-producing macroadenomas often present with hypogonadism and impotence. This report documents exacerbation of a PRL-secreting tumor after two separate 200-mg testosterone enanthate (T) injections despite continued bromocriptine (BRC) therapy. A 37-yr-old man with a 60-mm invasive tumor and a serum PRL level of 13,969 +/- 332 ng/ml (mean +/- SD) responded to BRC therapy with rapid disappearance of visual field defect, headache, and facial pain as well as decrease in serum PRL to 5,103 +/- 1,446 ng/ml. T injection was followed by severe headache, facial pain, and increase in PRL to 13,471 ng/ml. Visual field deterioration and increased tumor size (height, 40-43 mm) by computed tomography were documented. A relationship between T injection and exacerbation of the prolactinoma was not recognized until after a second T injection 3 months later. After that therapy, baseline PRL increased from 6,900 to 12,995 ng/ml. The hypothesis that T was aromatized to estradiol, directly stimulating lactotrophs, was supported by an increase in serum estradiol from 24 to 51 pg/ml after the second T injection. Although T treatment is accepted as appropriate therapy for hypogonadism in men with prolactinomas, it may not only interfere with the response of the tumor to BRC therapy, but even stimulate tumor growth and secretion.
Notes:
J C Prior, Y Vigna (1987)  Conditioning exercise and premenstrual symptoms.   J Reprod Med 32: 6. 423-428 Jun  
Abstract: Exercise is commonly listed as a remedy for the premenstrual syndrome (PMS), although no study has proven that it is an effective therapy. Numerous reports have suggested that exercise is associated with improved mood and symptoms. In those reports, however, the diagnosis of PMS was not clearly documented, nor was the exercise carefully controlled. Preliminary evidence suggests that exercise training in ovulatory, sedentary women and intensified training in women athletes decrease mild premenstrual symptoms. Although conditioning exercise is associated with short luteal phase and anovulatory cycles, decreases in mild premenstrual symptoms occur prior to menstrual cycle changes. Controlled studies of PMS and exercise training may not only document an effective, nonpharmacologic therapy for PMS but also clarify the hormonal etiology of this complex biobehavioral phenomenon.
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J C Prior, Y Vigna, D Sciarretta, N Alojado, M Schulzer (1987)  Conditioning exercise decreases premenstrual symptoms: a prospective, controlled 6-month trial.   Fertil Steril 47: 3. 402-408 Mar  
Abstract: Six months of exercise training was associated with decreased premenstrual symptoms in two groups of women. There was no change in symptoms in nontraining women. Eight sedentary (ST) women increased running from 0 to 76 +/- 26 km/cycle (mean +/- standard deviation) over 6 months and seven runners (MT) trained for a marathon (42.2 km). Six normally active, nontraining (C-NT) women kept their activity constant. Each subject completed monthly intensity-graded questionnaires or kept daily symptoms diaries concerning premenstrual symptoms. All monitored basal body temperature, weight, and exercise. Gonadal steroids were measured in ST women. For ST subjects, breast (P = 0.005), fluid (P = 0.01), and personal stress (P = 0.025) decreased. MT women experienced decreased fluid (P = 0.034) and depression (P = 0.014). Anxiety tended to decrease (P = 0.087). ST and MT subjects experienced decreases in premenstrual symptoms without documented hormonal, menstrual cycle, or weight changes. These symptom changes appear to be the earliest evidence of the effects of conditioning exercise on the reproductive system.
Notes:
1986
J C Prior, Y Vigna, N Alojada (1986)  Conditioning exercise decreases premenstrual symptoms. A prospective controlled three month trial.   Eur J Appl Physiol Occup Physiol 55: 4. 349-355  
Abstract: Conditioning exercise decreased premenstrual symptoms during 3 months of a prospective controlled training study. Eight women with normal ovulatory menstrual cycles began a running exercise training programme while completing intensity-graded questionnaires concerning molimina. Six sedentary control women followed the same protocol for 3 months but did not exercise. Oral basal temperatures evaluated by mean temperature analysis were obtained for all cycles. Exercise distance and time, average exercise heart rate, basal and maximal heart rate and body weights were recorded prospectively and evaluated during the control (0) and 3rd month of the study. Mid-luteal phase progesterone and estrogen levels were sampled during the analyzed cycles for the exercise group. Molimina did not change over 3 months time in the control group. The exercise group, after increasing distance run to 51.0 +/- 18.1 km/cycle at 3 months, showed decreases in overall molimina (scores on a 9-point scale) 6.5 +/- 1.8 to 3.5 +/- 0.9, p less than 0.01). Breast symptoms decreased from 8.3 +/- 0.7, p less than 0.005. Fluid symptoms also decreased from 7.3 +/- 1.8 to 5.5 +/- 0.9, p less than 0.025. Menstrual cycle intervals, luteal lengths, body weights and mid-luteal estrogen and progesterone levels were normal and unchanged. Moderate exercise training without major weight, hormonal or menstrual cycle alteration significantly decreased premenstrual symptoms.
Notes:
1985
P S Rennie, J C Prior, N Bruchovsky, P W Gout (1985)  Bioactive forms of serum lactogens: effects of treatment of prolactinoma patients with bromocriptine.   Clin Endocrinol (Oxf) 22: 1. 65-73 Jan  
Abstract: An in vitro bioassay for lactogenic hormones, based on the specific mitogenic effects of lactogens on cultured Nb2 node rat lymphoma cells, was used to measure the levels of lactogens in whole serum and in fractionated serum samples from three patients with prolactin (PRL) secreting pituitary adenomas. Under basal conditions, after pituitary stimulation, and following treatment with bromocriptine which greatly decreased the serum PRL levels, the bioassay (BA) results closely paralleled fluctuations in the sum of radioimmunoassay (RIA) estimates of serum PRL and growth hormone concentrations. The extreme sensitivity (10 pg/ml) of the BA facilitated measurement of PRL in fractions obtained after Sephadex G-100 chromatography of only 0.1 to 0.3 ml of sera from both untreated and bromocriptine-treated prolactinoma patients. In both types of samples, similar heterogenous patterns of bioactive PRL were observed, although most of the recovered activity appeared to be due to monomeric PRL. BA and RIA of fractions obtained after DEAE cellulose chromatography of sera from untreated prolactinoma patients revealed two PRL peaks, the first one containing 75% of the activity. Therapy with bromocriptine led to a reduction in the total serum PRL activity and, in particular, in the activity of the second peak.
Notes:
J C Prior, Y Vigna (1985)  Gonadal steroids in athletic women contraception, complications and performance.   Sports Med 2: 4. 287-295 Jul/Aug  
Abstract: Gonadal steroids are altered by the reproductive system's adaptation to conditioning exercise. Contraceptive options for the athletic woman include all measures appropriate for the sedentary woman. Barrier methods (always with spermicidal jelly) are the preferred choice. The cardiovascular risks, decreased aerobic performance, and shorter time to muscular exhaustion related to oral contraceptives make this a less desirable option. Potential complications from the steroid changes of intense exercise include: low oestrogen and progesterone with risk of loss of trabecular bone and early osteoporosis, and absent progesterone with low normal oestrogen levels associated with risk of endometrial or breast cancer. Therapeutic options for the amenorrhoeic or young athlete include supplemental oral calcium, cyclic oral progesterone, or possibly cyclic physiological oestrogen and progesterone. The anovulatory (usually older) athlete with regular menses needs cyclic progesterone. Medroxyprogesterone 10mg on days 16 to 25 of the cycle or for 10 days monthly can potentially prevent endometrial and breast cancer, give predictable cycles, improve trabecular bone balance and stimulate the return of ovulatory cycles. A practical approach to anovulatory infertility in the athlete includes a 10% reduction in exercise intensity and/or an increase in percentage body fat to 18 to 20%. Cyclic vaginal progesterone (25mg bid) can then treat short luteal phase cycles. With improved understanding of the hormonal adaptations to conditioning exercise, we will be better able to outline contraceptive and therapeutic options in the future.
Notes:
M D Whitaker, J C Prior, B Scheithauer, L Dolman, F Durity, M R Pudek (1985)  Gonadotrophin-secreting pituitary tumour: report and review.   Clin Endocrinol (Oxf) 22: 1. 43-48 Jan  
Abstract: A 34-year-old male with a pituitary adenoma was investigated and demonstrated to have hypersecretion of both gonadotrophins in the basal state. Immunocytochemical staining and electron microscopic examination were positive for tumour cells secreting FSH and LH. Presenting symptoms included visual disturbances, loss of libido, impotence, cold intolerance, frontal headaches, change in skin pigmentation and excessive weight gain. The patient denied alteration in hair distribution, had no acral features, galactorrhoea or gynaecomastia. Surgical extirpation resulted in complete amelioration of his symptoms over a three year follow-up period. Basal and stimulated pituitary function testing results returned to normal post-operatively. A review of the literature documents six other cases of pituitary tumour secreting both LH and FSH in the basal state. More commonly, the pituitary adenoma secretes FSH only. The literature is reviewed with regard to both types of tumour.
Notes:
1984
J C Prior, N C Alojado, J A Hunt, I S Begg (1984)  Use of tactile techniques for self-monitoring of blood glucose in visually impaired patients with diabetes mellitus.   Diabetes Care 7: 4. 313-317 Jul/Aug  
Abstract: Twenty-eight patients with type I diabetes mellitus, legally blind as a result of proliferative retinopathy, were recruited into a program designed to teach and evaluate tactile methods for self-monitoring of blood glucose (SMBG). Vision ranged from "blind" to "able to read large print." Techniques with wipe-off strips (Chemstrip bG or BM Test BG, Boehringer-Mannheim, Canada Ltd., Dorval, Quebec, Canada) use the opposite hand as a guide, operation of timing devices by touch, and special methods for labeling and storing strips. Methods with wash-off strips (Dextrostix, Ames Division, Miles Laboratories, Rexdale, Ontario, Canada) employ the fingers as a guide in directing the wash water. The accuracy of tactile methods was documented. Clinical parameters of glucose control improved in patients with adequate data after 6 mo of tactile SMBG. Glycosylated hemoglobin in 17 patients decreased from 11.3 +/- 2.1% to 9.4 +/- 1.5% (P = 0.005). Patients experienced significantly fewer reactions and low blood sugar readings as well as lowering of mean blood glucose values from 158 +/- 56 to 141 +/- 51 (P = 0.025).
Notes:
D C Daly, C A Walters, J C Prior, S T Kuslis, J Chapitis, J Andreoli, D H Riddick (1984)  Prolactin production from proliferative phase leiomyoma.   Am J Obstet Gynecol 148: 8. 1059-1063 Apr  
Abstract: In vivo and in vitro endometrial stromal synthesis of prolactin occurs after progesterone-induced decidualization. Synthesis of prolactin by myometrium in vitro suggests that cells whose embryologic origin is the loose mesenchyme surrounding the paramesonephric ducts may retain the capacity to synthesize prolactin. Since physiologic myometrial synthesis of prolactin has not been demonstrated in vivo, prolactin genome expression in pathologic conditions was considered. Follicular phase leiomyomas were diced to 8 mm3 and cultured in Dulbecco's modified Eagle's medium (DMEM) with either no hormones, estradiol 200 pg/ml, progesterone 20 ng/ml, or estradiol and progesterone. Media were sampled and changed every other day for 8 days, followed by culture in tritium-labeled leucine DMEM for 2 days. Portions of leiomyomas were homogenized for initial prolactin content, and all samples were assayed for prolactin by radioimmunoassay. Follicular phase leiomyomas contained prolactin (47 +/- 15 ng/gm) in excess of normal serum values. Synthesis was demonstrated during all time periods from leiomyomas not exposed to progesterone. Progesterone variably suppressed the synthesis of prolactin until after 144 hours of culture. Determination of molecular weight on a 60 by 1.5 cm Sephadex G-100 column revealed identical estimates for pituitary, decidual, and leiomyoma prolactin. Tritium-labeled leucine incorporation into prolactin was confirmed by immunoprecipitation of Sephadex G-100 column fractions. Similar antigenicity was confirmed by parallel dilution curves for pituitary, decidual, and leiomyoma prolactin. Preliminary bioactivity in lymphoma proliferation assays confirmed prolactin activity. The conclusion reached was that proliferative phase leiomyomas contained elevated prolactin presumably secondary to in vivo synthesis. This synthesis was confirmed in vitro.
Notes:
1983
C A Walters, D C Daly, J Chapitis, S T Kuslis, J C Prior, W F Kusmik, D H Riddick (1983)  Human myometrium: a new potential source of prolactin.   Am J Obstet Gynecol 147: 6. 639-644 Nov  
Abstract: Human myometrium is shown for the first time to produce prolactin in vitro. This prolactin is similar to pituitary prolactin by criteria of immunologic identity, gel chromatography and bioassay. The de novo synthesis of myometrical prolactin is supported by no detectable prolactin in initial tissue homogenate, nondetectable prolactin production during the first 24 hours of culture, cycloheximide inhibition of prolactin production with recovery of production in control medium, and tritiated leucine incorporation into prolactin. Although human myometrium is capable of producing prolactin without the addition of exogenous hormones, the addition of estrogen and progesterone, respectively, enhances and suppresses prolactin production in contrast to decidualized human endometrium where opposite effects on prolactin production are found.
Notes:
1982
J C Prior, E C Cameron, W J Knickerbocker, V P Sweeney, O Suchowersky (1982)  Dialysis encephalopathy and osteomalacic bone disease: a case-controlled study.   Am J Med 72: 1. 33-42 Jan  
Abstract: Nine patients on long-term hemodialysis with dialysis encephalopathy were studied, with sex matched control subjects for eight of the patients. Each patient with dialysis encephalopathy and control subject were contemporaries in a similar dialysis environment. Rib and other fractures were found in excess in the patients with dialysis encephalopathy (p less than 0.005 and p less than 0.01). These patients had less radiographic hyperparathyroid bone disease, and no more osteopenia as measured by metacarpal thickness than did their control counterparts. Severe osteomalacia was documented by bone biopsy in four of te patients. In a retrospective review of clinical, biochemical and pharmacologic differences, the patients with dialysis encephalopathy were significantly older at the start of dialysis (45.6 years versus 38.6 years, p less than 0.02) and had higher mean concentrations of blood urea nitrogen (BUN) and lower serum hemoglobin in the first year of dialysis than the control subjects. Blood pressure weight, creatinine, calcium, phosphate, alkaline phosphatase and a number of transfusions did not differ significantly. There was no difference in prescribed vitamin D and elemental aluminum in phosphate binders. This study demonstrates that patients with dialysis encephalopathy had more rib fractures without more parathyroid or osteopenic bone disease than did the control subjects and suggests that the etiology of dialysis encephalopathy and osteomalacia is multifactorial.
Notes:
J C Prior, K Cameron, B H Yuen, J Thomas (1982)  Menstrual cycle changes with marathon training: anovulation and short luteal phase.   Can J Appl Sport Sci 7: 3. 173-177 Sep  
Abstract: Fourteen normal women (self-selected from 180 women enrolled) in a marathon training clinic kept basal body temperature (BBT), mileage, and weight records for 48 cycles before the marathon. Entry criteria were: Age 20-45, gynecologic age greater than 5 years, no hormone use, or weight change in 3 months. The women were 35.2 +/- 5.6 years in age, 22.6 +/- 5.1 years gynecologic age, runners of 4.1 +/- 2.5 years with premenstrual symptoms, previous pregnancy 4/14, no infertility and 2/14 remote amenorrhea. BBT records were obtained and analyzed by Vollman's criteria (1977). There was no weight loss. 32/48 cycles were biphasic but only 16 were normal in the length of the premenstrual phase (PreM = luteal, nl 10 - 16 d) with a mean of 11.1 +/- 1.2 days. The other 16 biphasic cycles had short PreM phase of 6.4 +/- 1.8 days. Monophasic (M = anovulatory) cycles occurred in 16/48 records. Cycles which were abnormal (Short PreM and M) differed only in that usual run length was longer (9.6 - 9.9 miles) than in normal cycles (7.9 +/- 2.4 miles). Marathon training may be associated with normal length but M and short PreM type cycles.
Notes:
J C Prior (1982)  Endocrine "conditioning" with endurance training a preliminary review.   Can J Appl Sport Sci 7: 3. 148-156 Sep  
Abstract: The human individual responds as an entire organism to the effect of endurance training. Exercise physiologists have long documented cardiovascular, musculo-skeletal and metabolic effects of conditioning. Only recently are we beginning to understand that there are hormonal and hypothalamic changes which occur with conditioning. These hormonal changes probably serve similar adaptive functions as do the other conditioning responses. Careful controlled studies need to be performed of individuals prior to, early in conditioning, and following extended periods of conditioning looking at hypothalamic function, body morphometric characteristics, psychiatric and psychological testing and menstrual cycle data in order to better understand hormonal conditioning. When hormone changes occurring with endurance training are approached in this light, the complex inter-related alterations will begin to form a pattern. Further studies are needed to document the dynamic and reversible nature of these hormonal adaptations.
Notes:
1980
E C Cameron, J C Prior, H S Ballon (1980)  Hemodialysis patients with a unique mineralizing defect unresponsive to 1,25-dihydroxycholecalciferol. Dialysis osteomalacic syndrome.   Contrib Nephrol 18: 162-171  
Abstract: 5 patients are described who developed severe osteomalacia with spontaneous fractures after 2-4 years on dialysis. Phosphate control, vitamin D2 therapy and parathyroidectomy were ineffective. These individuals showed a hypercalcemic tendency but little histologic or radiographic evidence of osteitis fibrosa. After parathyroidectomy, the hypercalcemic tendency remained and bone biopsy revealed gross osteomalacia. A 6- to 12-month therapeutic trial with 1,25-dihydroxycholecalciferol (1,25[OH]2D3) in 3 did not arrest skeletal deterioration. 4 subsequently developed dialysis encephalopathy. These patients appear to have a unique mineralizing defect unresponsive to 1,25(OH)2D3. This "dialysis osteomalacic syndrome" may result from toxic substances associated with uremia or the hemodialysis regimen.
Notes:
1979
J C Prior, E C Cameron, H S Ballon, D S Lirenman, M V Moriarty, J D Price (1979)  Experience with 1,25-dihydroxycholecalciferol therapy in undergoing hemodialysis patients with progressive vitamin D2-treated osteodystrophy.   Am J Med 67: 4. 583-589 Oct  
Abstract: Six long-term hemodialysis patients with progressive skeletal deterioration during long-term pharmacologic vitamin D2 therapy were treated for six to 12 months with oral 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) to determine its therapeutic effectiveness in vitamin D2-unresponsive osteodystrophy. On bone biopsy, three of the patients had severe osteomalacia and three showed predominant osteitis fibrosa. Previous therapies, including phosphate binders and dialysis schedules, were maintained. The three patients with osteomalacia and the two with osteitis fibrosa showed clinical deterioration. There was no significant change in serum calcium, phosphate, alkaline phosphatase, bone densitometry, immunoreactive parathyroid hormone levels or bone histology. Roentgenograms showed multiple new fractures of ribs and femoral necks in the patients with osteomalacia and increased bone resorption in two of three patients with osteitis fibrosa. 1,25-(OH)2D3 dosage had to be decreased in all patients because of hypercalcemia with a mean tolerated dose of 0.22 microgram/day. In these patients, 1,25-(OH)2D3 was not effective therapy for progressive osteodystrophy unresponsive to pharmacologic vitamin D2.
Notes:
1967
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