Biomedical subjects

Steven R Cummings

Publications and source records attributed to Steven R Cummings.

At least 73 records · Page 4Linked to original sources

PubMed2003

Phytoestrogen supplements for the treatment of hot flashes: the Isoflavone Clover Extract (ICE) Study: a randomized controlled trial.

CONTEXT: Clinical trials demonstrating increased risk of cardiovascular disease and breast cancer among women randomized to hormone replacement therapy have increased interest in other therapies for menopausal symptoms. Dietary supplements containing isoflavones are widely used as alternatives to hormonal therapies for hot flashes, but there is a paucity of data supporting their efficacy. OBJECTIVE: To compare the efficacy and safety of 2 dietary supplements derived from red clover with placebo in symptomatic menopausal women. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo-controlled trial of menopausal women, aged 45 to 60 years, who were experiencing at least 35 hot flashes per week. The study was conducted between November 1999 and March 2001 at 3 US medical centers and included women who were recently postmenopausal (mean [SD], 3.3 [4.5] years since menopause) experiencing 8.1 hot flashes per day. Women were excluded if they were vegetarians, consumed soy products more than once per week, or took medications affecting isoflavone absorption. INTERVENTION: After a 2-week placebo run-in, 252 participants were randomly assigned to Promensil (82 mg of total isoflavones per day), Rimostil (57 mg of total isoflavones per day), or an identical placebo, and followed-up for 12 weeks. MAIN OUTCOME MEASURE: The primary outcome measure was the change in frequency of hot flashes measured by participant daily diaries. Secondary outcome measures included changes in quality of life and adverse events. RESULTS: Of 252 participants, 246 (98%) completed the 12-week protocol. The reductions in mean daily hot flash count at 12 weeks were similar for the Promensil (5.1), Rimostil (5.4), and placebo (5.0) groups. In comparison with the placebo group, participants in the Promensil group (41%; 95% confidence interval [CI], 29%-51%; P =.03), but not in the Rimostil group (34%; 95% CI, 22%-46%; P =.74) reduced hot flashes more rapidly. Quality-of-life improvements and adverse events were comparable in the 3 groups. CONCLUSION: Although the study provides some evidence for a biological effect of Promensil, neither supplement had a clinically important effect on hot flashes or other symptoms of menopause.

Dietary Supplements↗

PubMed2003

Relationship of changes in physical activity and mortality among older women.

CONTEXT: Physical activity has been related to reduced mortality, but it is not clear whether changes in physical activity affect mortality among older women. OBJECTIVE: To examine the relationship of changes in physical activity and mortality among older women. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study conducted at 4 US research centers (Baltimore, Md; Portland, Ore; Minneapolis, Minn; and Monongahela Valley, Pa) among 9518 community-dwelling white women aged 65 years or older who were assessed at baseline (1986-1988), 7553 of whom were reassessed at a follow-up visit (1992-1994; median, 5.7 years later). MAIN OUTCOME MEASURES: Walking and other physical activities at baseline and follow-up; vital status, with cause of death confirmed by death certificates/discharge summaries, tracked for up to 12.5 years after baseline (up to 6.7 years after the follow-up visit). RESULTS: Compared with continually sedentary women, those who increased physical activity levels between baseline and follow-up had lower mortality from all causes (hazard rate ratio [HRR], 0.52; 95% confidence interval [CI], 0.40-0.69), cardiovascular disease (HRR, 0.64; 95% CI, 0.42-0.97), and cancer (HRR, 0.49; 95% CI, 0.29-0.84), independent of age, smoking, body mass index, comorbid conditions, and baseline physical activity level. Associations between changes in physical activity and reduced mortality were similar in women with and without chronic diseases but tended to be weaker among women aged at least 75 years and among those with poor health status. Women who were physically active at both visits also had lower all-cause mortality (HRR, 0.68; 95% CI, 0.56-0.82) and cardiovascular mortality (HRR, 0.62; 95% CI, 0.44-0.88) than sedentary women. CONCLUSION: Increasing and maintaining physical activity levels could lengthen life for older women but appears to provide less benefit for women aged at least 75 years and those with poor health status.

Aged↗

PubMed2003

The relation of C-reactive protein levels to total and cardiovascular mortality in older U.S. women.

PURPOSE: To determine whether serum C-reactive protein levels, a sensitive indicator of inflammation, are associated with the risk of cardiovascular mortality among older women. METHODS: We conducted a case-cohort study within the Study of Osteoporotic Fractures, a population-based study involving 9,704 women aged > or = 65 years from four U.S. centers. We randomly selected 400 women from the entire cohort plus an additional random sample of 92 women from the 1,125 women in the cohort who had died during the first 6 years of follow-up. Baseline serum C-reactive protein levels were measured using a high-sensitivity immunoassay. Cause-specific mortality was ascertained by review of death certificates and hospitalization records. Multivariable Cox proportional hazards regression was used to determine the association between C-reactive protein levels and cardiovascular mortality. RESULTS: During 6 years of follow-up, 150 of the 492 women died, including 52 who died of cardiovascular disease. After adjusting for potential confounders, women with C-reactive protein levels in the highest quartile (>3.0 mg/L) had a 8.0-fold (95% confidence interval [CI]: 2.2 to 29) greater risk of cardiovascular mortality than those in the lowest quartile (< or = 1.0 mg/L). The association remained strong in women who did not smoke or take estrogen, and when early deaths were excluded. Women who smoked and whose C-reactive protein levels were above the first quartile had a very high risk of cardiovascular mortality (relative risk [RR] = 13; 95% CI: 3.4 to 47). C-reactive protein levels were not associated with noncardiovascular mortality (RR = 0.92; 95% CI: 0.4 to 2.1). CONCLUSION: C-reactive protein level was an independent predictor of cardiovascular mortality in older women.

Age Distribution↗

PubMed2003

Intentional and unintentional weight loss increase bone loss and hip fracture risk in older women.

OBJECTIVES: To test the hypothesis that unintentional weight loss increases the rate of bone loss and risk of hip fracture more than intentional weight loss. DESIGN: Prospective cohort study. SETTING: Four communities within the United States. PARTICIPANTS: Six thousand seven hundred eighty-five elderly white women with measurement of weight change and assessment of intention to lose weight. MEASUREMENTS: Weight change between baseline and fourth examinations (average 5.7 years between examinations) and assessment of intention to lose weight. Weight loss was defined as a decrease of 5% or more from baseline weight, stable weight was defined as less than a 5% change from baseline weight, and weight gain was defined as an increase of 5% or more from baseline weight. Rate of change in bone mineral density at the hip between fourth and sixth examinations (average 4.4 years between examinations) was measured using dual-energy x-ray absorptiometry. Incident hip fractures occurring after the fourth examination until June 1, 2001 (average follow-up 6.6 years) was confirmed using radiographic reports. RESULTS: The adjusted average rate of decline in total hipbone density steadily increased from -0.52% per year in women with weight gain to -0.68% per year in women with stable weight to -0.92% per year in women with weight loss (P-value for trend <.001). Higher rates of hip-bone loss were observed in women with weight loss irrespective of body mass index (BMI) or intention to lose weight. During follow-up of an average 6.6 years after the fourth examination, 400 (6%) of the cohort suffered a first hip fracture. Women with weight loss had 1.8 times the risk (95% confidence interval (CI)=1.43-2.24) of subsequent hip fracture as those with stable or increasing weight. The association between weight loss and increased risk of hip fracture was consistent across categories of BMI and intention to lose weight. Even voluntary weight loss in overweight women with a BMI of 25.9 kg/m2 (median) or greater increased the risk of hip fracture (multivariate hazard ratio=2.48, 95% CI=1.33-4.62). CONCLUSION: Older women who experience weight loss in later years have increased rates of hip-bone loss and a two-fold greater risk of subsequent hip fracture, irrespective of current weight or intention to lose weight. These findings indicate that even voluntary weight loss in overweight elderly women increases hip fracture risk.

Aged↗

PubMed2003

Lipid-lowering drug use and breast cancer in older women: a prospective study.

OBJECTIVE: To test the hypothesis that use of lipid-lowering drugs reduces the risk of breast cancer in older women. METHODS: This was a multicenter prospective cohort study conducted at four community-based clinical centers in the United States, including 7528 Caucasian women, mean age 77 years. The main outcome measure was incident breast cancer confirmed by medical record and pathology reports identified over an average of 6.8 years (244 cases). RESULTS: The use of lipid-lowering drugs was reported by 576 women (7.7%). The age-adjusted incidence of breast cancer was 3.1/1000 person-years among statin users, 1.4 among women using other lipid-lowering agents, and 5.0 among nonusers. After adjustment for age and body weight, the relative risk (RR) of breast cancer among statin users was 0.28 (95% confidence intervals [CI] 0.09-0.86), and among women who used other lipid-lowering drugs, it was 0.37 (95% CI 0.14-0.99) in comparison to nonusers. The combined group of lipid-lowering drug users had a 68% reduction in the risk of breast cancer (95% CI 32%-85%). Further adjustment for hormone use, family history of breast cancer, mammography use, or other risk factors did not alter the results. CONCLUSIONS: Older women who use lipid-lowering drugs may have a reduced risk of breast cancer. Given the widespread use of statins in older women, these results could have a large public health impact. However, these findings need confirmation in other prospective studies, as they were based on a small number of breast cancer events.

Aged↗

PubMed2003

A new framework for describing and quantifying the gap between proof and practice.

BACKGROUND: Substantial gaps often exist between every day practice and best practice as defined by research evidence. We present a framework for defining, analyzing, and quantifying such proof-to-practice gaps. METHOD: An intervention's use can be plotted over time as ideal and actual uptake curves among candidates and noncandidates. Gaps of underuse are deviations from ideal uptake among candidates and can be quantified as underuse NNPs (Number Not Prevented): the number of disease events each year that would have been prevented, but were not, because of underuse among candidates of the intervention. Gaps of overuse are deviations from ideal uptake among non candidates and can be similarly quantified as overuse NNPs. RESULTS: Applying our method to the underuse of beta-blockers at hospital discharge postmyocardial infarction (MI) in the United States demonstrates an annual NNP of 2995 first-year post-MI deaths not prevented (sensitivity analysis range 455-20,409). Our NNP analysis framework highlights challenges to the determination of efficacy and efficiency, the definition of what constitutes proof, rapid recognition of proof when it does occur, the definition of eligible candidates, and the definition of the proportion of candidates treated. CONCLUSION: League tables of NNPs can help policy makers compare the clinical consequences of underuse and overuse of diverse interventions, while the NNP framework provides a systematic approach for describing and analyzing the components of proof-to-practice gaps. Such gap analyses can help organizations direct their resources to reducing gaps of greatest clinical consequence.

Adrenergic beta-Antagonists↗

PubMed2003

Estrogen metabolites and the risk of breast cancer in older women.

BACKGROUND: Women who metabolize a large proportion of their estrogen via the 16alpha hydroxylation pathway could be at a higher risk of breast cancer. The objective of this study was to test the hypothesis that serum concentrations of 2-hydroxyestrone (2-OHE1) and 16alpha-hydroxyestrone (16alpha-OHE1), as well as their ratio, predict the risk of breast cancer in older women. METHODS: We performed a case-cohort study of 272 women with confirmed incident breast cancer and 291 controls chosen randomly from the cohort. Estrogen metabolites were measured in serum collected at the baseline examination and stored at -120 degrees C. Incident breast cancers were confirmed by medical records and pathology reports during an average follow-up of 8.7 years. RESULTS: Mean concentrations of 2-OHE1 and 16alpha-OHE1, adjusted for age and body mass index, were 3% to 4% higher in cases compared with controls: 2-OHE1 was 176 pg/mL and 169 pg/mL and 16alpha-OHE1 was 233 pg/mL and 226 pg/mL in cases and controls, respectively. There was, however, no difference in the ratio of 2-OHE1 to 16alpha-OHE1. The risk of breast cancer in women with the highest quartile of this ratio compared with those in the lowest quartile was 1.17 (95% confidence interval = 0.73-1.87). CONCLUSION: The study results do not support the hypothesis that the ratio of 2-OHE1 to 16alpha-OHE1 predicts breast cancer risk.

Aged↗

PubMed2003

BMD at multiple sites and risk of fracture of multiple types: long-term results from the Study of Osteoporotic Fractures.

UNLABELLED: In a large cohort of U.S. women aged 65 and older, we report the relationships of BMD measured at several sites, and subsequent fracture risk at multiple sites over > 8 years of follow-up. Although we found almost all fracture types to be related to low BMD, the overall proportion of fractures attributable to low BMD is modest. INTRODUCTION: Although several studies have reported the relationship between bone mineral density (BMD) and subsequent fracture risk, most have been limited by short follow-up time, BMD measures at only one or two sites, or availability of data for only select fracture types. MATERIALS AND METHODS: In the multicenter Study of Osteoporotic Fractures (SOF), we studied the relationship of several different BMD measures to fracture risk of multiple types in 9704 non-black women aged 65 and older. We previously reported on the relationship of peripheral BMD measures to risk of several types of fracture during an average 2.2-year follow-up period. In this expanded analysis, we present results of the relationship of both peripheral and central BMD measures and fractures of multiple types during 10.4 and 8.5 years of follow-up, respectively. We also report population attributable risk (PAR) estimates for osteoporosis and risk of several types of fracture. RESULTS: Our results show that almost all types of fractures have an increased incidence in women with low BMD. However, hip BMD is somewhat more strongly related to most of the fracture types studied than spine or peripheral BMD measures. Nonetheless, the proportion of fractures attributable to osteoporosis (based on a standard definition of osteoporosis) is modest, ranging from < 10% to 44% based on the most commonly used definition of osteoporosis (BMD T-score < -2.5). CONCLUSION: Finding effective prevention strategies for fractures in older women will require additional interventions beside preventions for bone loss, such as prevention of falls and other fracture risk factors.

Aged↗

PubMed2003

Nulliparity and fracture risk in older women: the study of osteoporotic fractures.

Whether nulliparity increases fracture risk is unclear from prior studies, which are limited by small samples or lack of measured bone mineral density. No study has evaluated whether the effect of parity differs by skeletal site. We prospectively analyzed the relationship of parity to the risk of incident nontraumatic hip, spine, and wrist fractures in 9704 women aged 65 years or older participating in the Study of Osteoporotic Fractures to determine if parity reduces postmenopausal fracture risk, and if so, if this risk reduction is (1) greater at weight-bearing skeletal sites and (2) independent of bone mineral density. Parity was ascertained by self-report. Incident hip and wrist fractures were determined by physician adjudication of radiology reports (mean follow-up, 9.8 years) and spine fractures by morphometric criteria on serial radiographs. The relationship of parity to hip and wrist fracture was assessed by proportional hazards models. Spine fracture risk was evaluated by logistic regression. Compared with parous women, nulliparous women (n = 1835, 19%) had an increased risk of hip and spine, but not wrist, fractures. In multivariate models, parity remained a significant predictor only for hip fracture. Nulliparous women had a 44% increased risk of hip fractures independent of hip bone mineral density (hazards ratio, 1.44; 95% CI, 1.17-1.78). Among parous women, each additional birth reduced hip fracture risk by 9% (p = 0.03). Additionally, there were no differences in mean total hip, spine, or radial bone mineral density values between nulliparous and parous women after multivariate adjustment. In conclusion, childbearing reduces hip fracture risk by means that may be independent of hip bone mineral density.

Aged↗

PubMed2002

Clinical use of bone densitometry: scientific review.

CONTEXT: Osteoporosis causes substantial morbidity and costs $13.8 billion annually in the United States. Measurement of bone mass by densitometry is a primary part of diagnosing osteoporosis and deciding a preventive treatment course. Bone mineral densitometry has become more widely available and commonly used in practice. OBJECTIVE: To review evidence about the value of various clinical applications of bone densitometry. DATA SOURCES: A MEDLINE search was performed to update previous meta-analyses of the relationship between various measurements of bone density and risk of vertebral and hip fracture. We used data from the prospective Study of Osteoporotic Fractures to estimate risk of fracture from bone density and age in postmenopausal women. STUDY SELECTION AND DATA EXTRACTION: When available, meta-analyses and systematic reviews are emphasized in the review. DATA SYNTHESIS: Bone mineral density (BMD) predicts fracture and can be used in combination with age to estimate absolute risk of fractures in postmenopausal white women. Hip BMD predicts hip fracture more strongly than other measurements of BMD. There are insufficient data to translate BMD results into risk of fracture for men and nonwhite women. The benefits of treatments to prevent fractures depend on BMD: women with osteoporosis have a greater risk of fractures and greater benefit from treatments than women without osteoporosis. CONCLUSIONS: Guidelines based on systematic reviews and a cost-effectiveness analysis have suggested that it is worthwhile to measure BMD in white women older than 65 years and perhaps to use risk factors to select younger postmenopausal women for densitometry. Other potential clinical applications of BMD that have not yet been adequately studied include screening men or nonwhite women, monitoring BMD in patients receiving treatment, and using BMD to identify patients who should be evaluated for secondary causes of osteoporosis.

Absorptiometry, Photon↗

PubMed2002

Clinical use of bone densitometry: clinical applications.

Osteoporosis represents a difficult problem for physicians because, although many diagnostic tests are available, interpreting their results is not straightforward. As a result, many patients, even those with clear indications such as long-term steroid therapy or vertebral fractures on radiography, do not get screened or treated. Current evidence-based guidelines recommend screening for all white women older than 65 years and not already receiving an osteoporosis treatment and for many nonwhite women. For postmenopausal women who are younger than 65 years and have strong risk factors for osteoporosis, screening may also be beneficial. The optimal testing strategy depends on what is available locally. The best role for follow-up testing is still being defined, and interpretation of such testing is tricky. Reports of results can be hard to understand; a randomized controlled trial of clearer reports increased testing and decreased confusion about the meaning of test results. Densitometry might be more effectively used in practice if strategies such as having patients fill out a short questionnaire to assess for risk factors or creating a nurse-based system were used to identify patients. Clinicians need better approaches for identifying patients most likely to benefit from screening, systems that facilitate their application, and test results that are easy to interpret.

Absorptiometry, Photon↗

PubMed2002

American Society of Clinical Oncology technology assessment of pharmacologic interventions for breast cancer risk reduction including tamoxifen, raloxifene, and aromatase inhibition.

OBJECTIVE: To update an evidence-based technology assessment of chemoprevention strategies for breast cancer risk reduction. POTENTIAL INTERVENTIONS: Tamoxifen, raloxifene, aromatase inhibition, and fenretinide. OUTCOMES: Outcomes of interest include breast cancer incidence, breast cancer-specific survival, overall survival, and net health benefit. EVIDENCE: A comprehensive, formal literature review was conducted for relevant topics. Testimony was collected from invited experts and interested parties. The American Society of Clinical Oncology (ASCO) prescribed technology assessment procedure was followed. VALUES: More weight was given to published randomized trials. BENEFITS/HARMS: A woman's decision regarding breast cancer risk reduction strategies is complex and will depend on the importance and weight attributed to information regarding both cancer- and noncancer-related risks and benefits. CONCLUSIONS: For women with a defined 5-year projected breast cancer risk of > or= 1.66%, tamoxifen (at 20 mg/d for 5 years) may be offered to reduce their risk. Risk/benefit models suggest that greatest clinical benefit with least side effects is derived from use of tamoxifen in younger (premenopausal) women (who are less likely to have thromboembolic sequelae and uterine cancer), women without a uterus, and women at higher breast cancer risk. Data do not as yet suggest that tamoxifen provides an overall health benefit or increases survival. In all circumstances, tamoxifen use should be discussed as part of an informed decision-making process with careful consideration of individually calculated risks and benefits. Use of tamoxifen combined with hormone replacement therapy or use of raloxifene, any aromatase inhibitor or inactivator, or fenretinide to lower the risk of developing breast cancer is not recommended outside of a clinical trial setting. This technology assessment represents an ongoing process and recommendations will be updated in a timely matter. VALIDATION: The conclusions were endorsed by the ASCO Health Services Research Committee and the ASCO Board of Directors.

Antineoplastic Agents, Hormonal↗

PubMed2002

Epidemiology and outcomes of osteoporotic fractures.

Bone mass declines and the risk of fractures increases as people age, especially as women pass through the menopause. Hip fractures, the most serious outcome of osteoporosis, are becoming more frequent than before because the world's population is ageing and because the frequency of hip fractures is increasing by 1-3% per year in most areas of the world. Rates of hip fracture vary more widely from region to region than does the prevalence of vertebral fractures. Low bone density and previous fractures are risk factors for almost all types of fracture, but each type of fracture also has its own unique risk factors. Prevention of fractures with drugs could potentially be as expensive as medical treatment of fractures. Therefore, epidemiological research should be done and used to identify individuals at high-risk of disabling fractures, thereby allowing careful allocation of expensive treatments to individuals most in need.

Age Distribution↗

PubMed2002

Serum estradiol level and risk of breast cancer during treatment with raloxifene.

CONTEXT: As endogenous estradiol increases, risk of breast cancer increases. Raloxifene competes with endogenous estrogen for binding to estrogen receptors in breast tissue. A woman's estradiol level may alter the effects of raloxifene on breast cancer and other outcomes. OBJECTIVE: To test the hypothesis that raloxifene reduces breast cancer risk more in women with relatively high estradiol levels than in women with very low estradiol levels. DESIGN: Analysis of the Multiple Outcomes of Raloxifene Evaluation, a randomized, double-blind, placebo-controlled trial conducted from 1994 to 1999. SETTING: One hundred eighty community settings and medical practices in 25 countries including the United States. PARTICIPANTS: A total of 7290 postmenopausal women aged 80 years or younger with osteoporosis who had baseline serum estradiol concentrations measured by a central laboratory using a sensitive assay. Women with a history of breast cancer or estrogen use were excluded. INTERVENTION: Participants were randomly assigned to receive 60 mg/d or 120 mg/d of raloxifene (n = 4843) or matching placebo (n = 2447) for 4 years. MAIN OUTCOME MEASURE: New cases of histopathologically confirmed breast cancer in the treatment and placebo groups, stratified by estradiol levels. RESULTS: In the placebo group, women with estradiol levels greater than 10 pmol/L (2.7 pg/mL) had a 6.8-fold higher rate of breast cancer (3.0% per 4 years; 95% confidence interval [CI], 1.8%-4.1%) than that of women with undetectable estradiol levels (0.6% per 4 years; 95% CI, 0%-1.1%; P =.005 for trend). Women with estradiol levels greater than 10 pmol/L in the raloxifene group had a rate of breast cancer that was 76% (95% CI, 53%-88%) lower than that of women with estradiol levels greater than 10 pmol/L in the placebo group (absolute rate reduction, 2.2% [95% CI, 1.0%-3.5%; number needed to treat = 45]). In contrast, women with undetectable estradiol levels had similar breast cancer risk whether or not they were treated with raloxifene (risk difference, -0.1%; 95% CI, -0.8% to 0.6%; P =.02 for the interaction). In this cohort, treating women with estradiol levels greater than 10 pmol/L with raloxifene for 4 years would have avoided 47% of breast cancer cases. CONCLUSIONS: Measurement of estradiol level by sensitive assay in postmenopausal women identifies those at high risk of breast cancer who may benefit most from raloxifene. If confirmed, this suggests that measuring estradiol and treating women with high estradiol levels could substantially reduce the rate of breast cancer among postmenopausal women.

Aged↗

PubMed2002

Very low prevalence of hip osteoarthritis among Chinese elderly in Beijing, China, compared with whites in the United States: the Beijing osteoarthritis study.

OBJECTIVE: To compare the prevalence of osteoarthritis (OA) of the hip among elderly persons in China and the US. METHODS: We recruited a population-based sample of 1,506 persons (82% of those enumerated) ages > or = 60 years living in Beijing, China. Subjects answered questions about joint symptoms and underwent radiography of the pelvis. Radiographs of the Beijing subjects were intermingled with hip radiographs of white women ages > or = 65 years from the Study of Osteoporotic Fractures (SOF) and white men and women ages 60-74 years from the First National Health and Nutrition Examination Survey (NHANES-I) and were then interpreted. Radiographic hip OA was defined as the presence of 1 of the following 3 findings in either hip: minimum joint space of < or = 1.5 mm, definite osteophytes and joint space narrowing, or > or = 3 radiographic features of OA. Symptomatic hip OA was defined as both radiographic OA and hip pain. RESULTS: The crude prevalence of radiographic hip OA in Chinese ages 60-89 years was 0.9% in women and 1.1% in men; it did not increase with age. Chinese women had a lower age-standardized prevalence of radiographic hip OA compared with white women in the SOF (age-standardized prevalence ratio 0.07) and the NHANES-I (prevalence ratio 0.22). Chinese men had a lower prevalence of radiographic hip OA compared with white men of the same age in the NHANES-I (prevalence ratio 0.19). There were no cases of symptomatic hip OA in the Chinese men and only 1 case in the Chinese women; 35 cases were expected in both sexes. CONCLUSION: This is the first population-based study of hip OA in China to use standardized radiographic methods and definitions. We found that hip OA was 80-90% less frequent than in white persons in the US. Identification of the genetic and environmental factors that underlie these differences may help elucidate the etiology and prevention of hip OA.

Aged↗

PubMed2002

Improvement in spine bone density and reduction in risk of vertebral fractures during treatment with antiresorptive drugs.

PURPOSE: To estimate how much the improvement in bone mass accounts for the reduction in risk of vertebral fracture that has been observed in randomized trials of antiresorptive treatments for osteoporosis. METHODS: After a systematic search, we conducted a meta-analysis of 12 trials to describe the relation between improvement in spine bone mineral density and reduction in risk of vertebral fracture in postmenopausal women. We also used logistic models to estimate the proportion of the reduction in risk of vertebral fracture observed with alendronate in the Fracture Intervention Trial that was due to improvement in bone mineral density. RESULTS: Across the 12 trials, a 1% improvement in spine bone mineral density was associated with a 0.03 decrease (95% confidence interval [CI]: 0.02 to 0.05) in the relative risk (RR) of vertebral fracture. The reductions in risk were greater than predicted from improvement in bone mineral density; for example, the model estimated that treatments predicted to reduce fracture risk by 20% (RR = 0.80), based on improvement in bone mineral density, actually reduce the risk of fracture by about 45% (RR = 0.55). In the Fracture Intervention Trial, improvement in spine bone mineral density explained 16% (95% CI: 11% to 27%) of the reduction in the risk of vertebral fracture with alendronate. CONCLUSION: Improvement in spine bone mineral density during treatment with antiresorptive drugs accounts for a predictable but small part of the observed reduction in the risk of vertebral fracture.

Alendronate↗

PubMed2002

Bone mineral density is not diminished by mild to moderate chronic renal insufficiency.

BACKGROUND: Persons with end-stage renal disease are at higher risk for osteopenia and hip fracture relative to the age-matched general population. Persons with mild to moderate chronic renal insufficiency (CRI) may have reduced bone mineral density (BMD) as a result of abnormalities in acid-base and vitamin D-parathyroid hormone homeostasis. METHODS: We analyzed data on 13,848 adults aged 20 and above from the Third National Health and Nutrition Examination Survey (NHANES III; 1988-1994). Regression models were used to determine the relationship between femoral BMD and renal function, the latter assessed using serum creatinine, blood urea nitrogen or Cockcroft-Gault creatinine clearance. To control for confounding, we fit sex-stratified models that adjusted for age, weight, height, race-ethnicity, menopausal status, estrogen use, activity level, family history of osteoporosis, diuretic use, and dietary intake of calcium and alcohol. RESULTS: Although subjects with reduced renal function had significantly lower femoral BMD in unadjusted analysis, the association between CRI and bone mineral density was extinguished after adjustment in the multivariate models. In fact, controlling for only sex, age and weight was sufficient to extinguish any negative association between decreased renal function and decreased bone mineral density. CONCLUSION: Although subjects with worse renal function have significantly lower femoral BMD, this association can be explained by confounding, principally by sex, age and weight. After taking into account the facts that women, older individuals and smaller individuals have less renal function and lower BMD, renal function itself is not independently associated with BMD.

Adult↗

PubMed2002

Rapid resting heart rate: a simple and powerful predictor of osteoporotic fractures and mortality in older women.

OBJECTIVES: To determine whether resting heart rate is associated with several types of osteoporotic fractures, mortality, and cause-specific mortality in older women. DESIGN: A prospective cohort study. SETTING: Four communities across the United States. PARTICIPANTS: We prospectively assessed resting pulse rate in 9,702 women aged 65 and older enrolled in the Study of Osteoporotic Fractures. MEASUREMENTS: Resting pulse was measured in the supine position. Hip, humerus, pelvis, rib, ankle, and wrist fractures were identified by self-report and validated by radiographs. Incident vertebral fractures were assessed by quantitative morphometry. Cause-specific mortality was assessed from death certificates and hospital discharge summaries. RESULTS: Women with resting heart rates of greater than 80 beats per minute (bpm) (n = 1,140 (12%)) had an adjusted 1.6-fold (95% confidence interval (CI) = 1.2-2.0) increased risk of either a hip, pelvis, or rib fracture and a 1.9-fold (95% CI = 1.4-2.5) increased risk of vertebral fracture. A heart rate of 80 bpm or greater was also associated with 1.4-fold (95% Cl = 1.2-1.5) increased all-cause mortality and 1.5-fold (95% CI = 1.2-2.1) increased coronary heart disease mortality. Investigating resting heart rate as a continuous variable, we detected a general pattern of increasing risks with higher heart rate that could not be explained by age, weight, poor health, physical activity, hyperthyroidism, or smoking. CONCLUSIONS: Older women with resting heart rates of 80 bpm or more have an increased risk of several osteoporotic fractures and of mortality that is not explained by other risk factors. Heart rate may be a simple tool for assessing risk of fracture and of death from coronary heart disease in older women.

Age Factors↗