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Steven R Cummings

Publications and source records attributed to Steven R Cummings.

At least 19 recordsLinked to original sources
PubMed2007

Predictors of non-spine fracture in elderly men: the MrOS study.

UNLABELLED: We examined determinants of nonvertebral fracture in elderly men from six U.S. communities followed an average of 4.1 years. Six clinical risk factors predicted fracture risk independent of hip BMD: tricyclic antidepressant use, previous fracture, inability to complete a narrow walk trial, falls in previous year, age > or =80 years, and depressed mood. INTRODUCTION: There are few prospective studies of fracture determinants in men. We examined the associations between a comprehensive set of clinical risk factors and risk of nonspine fracture in older men and whether determinants of fracture risk were independent of total hip BMD. MATERIALS AND METHODS: A total of 5995 men > or =65 years of age were recruited from six communities in the Unites States and followed prospectively for an average of 4.1 years. Baseline assessments of demographic, lifestyle, medical history, functional status, anthropometry, and cognitive, visual, and neuromuscular function were assessed by questionnaire or examination. Triannual mailed questionnaires ascertained incident fracture; reported fractures were adjudicated by physicians using medical records and X-ray reports. Proportional hazards models were used to develop multivariable models, selecting variables and controlling for BMD. RESULTS: Of 5876 men, 4.7% (N = 275) reported an incident nonspine fracture during follow-up (11.46/1000 person-years). Tricyclic antidepressant use (hazard ratio [HR], 2.36; 95% CI, 1.25-4.46), history of fracture at or after age 50 (HR, 2.07; 95% CI, 1.62-2.65), inability to complete a narrow walk trial (HR, 1.70; 95% CI, 1.23-2.34), falls in previous year (HR, 1.59; 95% CI, 1.23-2.05), age > or =80 years (HR, 1.33; 95% CI, 1.01-1.76), depressed mood (HR, 1.72; 95% CI, 1.00-2.95), and decreased total hip BMD (HR, 1.53; 95% CI, 1.34-1.74) were independently related to increased risk. Compared with having none (48.0% of men), having three or more of the clinical risk factors (4.9% of men) increased fracture risk 5-fold, independent of BMD. Having three or more risk factors and being in the lowest tertile of BMD was associated with a 15-fold greater risk than having no risk factors and being in the highest BMD tertile. CONCLUSIONS: Several clinical risk factors were independently associated with nonspine fractures in elderly men. The combination of multiple risk factors and low BMD was a very powerful indicator of fracture risk.

Aged↗
PubMed2006

Effects of continuing or stopping alendronate after 5 years of treatment: the Fracture Intervention Trial Long-term Extension (FLEX): a randomized trial.

CONTEXT: The optimal duration of treatment of women with postmenopausal osteoporosis is uncertain. OBJECTIVE: To compare the effects of discontinuing alendronate treatment after 5 years vs continuing for 10 years. DESIGN AND SETTING: Randomized, double-blind trial conducted at 10 US clinical centers that participated in the Fracture Intervention Trial (FIT). PARTICIPANTS: One thousand ninety-nine postmenopausal women who had been randomized to alendronate in FIT, with a mean of 5 years of prior alendronate treatment. INTERVENTION: Randomization to alendronate, 5 mg/d (n = 329) or 10 mg/d (n = 333), or placebo (n = 437) for 5 years (1998-2003). MAIN OUTCOME MEASURES: The primary outcome measure was total hip bone mineral density (BMD); secondary measures were BMD at other sites and biochemical markers of bone remodeling. An exploratory outcome measure was fracture incidence. RESULTS: Compared with continuing alendronate, switching to placebo for 5 years resulted in declines in BMD at the total hip (-2.4%; 95% confidence interval [CI], -2.9% to -1.8%; P<.001) and spine (-3.7%; 95% CI, -4.5% to -3.0%; P<.001), but mean levels remained at or above pretreatment levels 10 years earlier. Similarly, those discontinuing alendronate had increased serum markers of bone turnover compared with continuing alendronate: 55.6% (P<.001) for C-telopeptide of type 1 collagen, 59.5% (P < .001) for serum n = propeptide of type 1 collagen, and 28.1% (P<.001) for bone-specific alkaline phosphatase, but after 5 years without therapy, bone marker levels remained somewhat below pretreatment levels 10 years earlier. After 5 years, the cumulative risk of nonvertebral fractures (RR, 1.00; 95% CI, 0.76-1.32) was not significantly different between those continuing (19%) and discontinuing (18.9%) alendronate. Among those who continued, there was a significantly lower risk of clinically recognized vertebral fractures (5.3% for placebo and 2.4% for alendronate; RR, 0.45; 95% CI, 0.24-0.85) but no significant reduction in morphometric vertebral fractures (11.3% for placebo and 9.8% for alendronate; RR, 0.86; 95% CI, 0.60-1.22). A small sample of 18 transilial bone biopsies did not show any qualitative abnormalities, with bone turnover (double labeling) seen in all specimens. CONCLUSIONS: Women who discontinued alendronate after 5 years showed a moderate decline in BMD and a gradual rise in biochemical markers but no higher fracture risk other than for clinical vertebral fractures compared with those who continued alendronate. These results suggest that for many women, discontinuation of alendronate for up to 5 years does not appear to significantly increase fracture risk. However, women at very high risk of clinical vertebral fractures may benefit by continuing beyond 5 years. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT 00398931.

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PubMed2006

A 55-year-old woman with osteopenia.

About half of postmenopausal women have a bone density T score at the femoral neck between -1.0 and -2.5. Bone density in this range was termed "osteopenia" by a World Health Organization working group. Osteopenia is not a disease and the label can cause unnecessary anxiety. Osteopenia encompasses a wide range of fracture risks; an individual patient's risk can be estimated from her age, bone mineral density, and clinical risk factors. Regardless of bone mineral density, regular exercise and adherence with vitamin D and calcium intake may reduce the risk of hip fracture. Osteopenia by itself is not an indication for treatment. Decisions about pharmacological treatment to prevent fractures should be based on the patient's risk of fractures, evidence about the efficacy and nonskeletal effects of the specific treatment, and the patient's preferences.

Bone Density↗
PubMed2006

Endogenous testosterone levels, physical performance, and fall risk in older men.

BACKGROUND: Gonadal steroid levels decline with age in men. Whether low testosterone levels affect the development of common age-related disorders, including physical functioning and falling, is unclear. METHODS: This longitudinal, observational follow-up study sought to determine whether low testosterone levels are associated with physical performance and fall risk in older men. A total of 2587 community-based men aged 65 to 99 years were selected using a stratified random sampling scheme from a study cohort of 5995 volunteers. Bioavailable testosterone and estradiol levels and physical performance measures were determined from baseline. Incident falls were ascertained every 4 months during 4 years of follow-up. Generalized estimating equations were used to estimate risk ratios for the relation of sex steroids to falls. RESULTS: Fifty-six percent of the men reported at least 1 fall; many fell frequently. Lower bioavailable testosterone levels were associated with increased fall risk. Men with testosterone levels in the lowest quartile had a 40% higher fall risk than those in the highest quartile. The effect of low testosterone levels was most apparent in younger men (65-69 years) (relative risk, 1.8; 95% confidence interval, 1.2-2.7); testosterone level was not associated with falls in the oldest men (>/=80 years). Lower testosterone concentrations were associated with reduced physical performance. However, the association between low testosterone levels and fall risk persisted despite adjustment for performance. CONCLUSIONS: Falls were common among older men. Fall risk was higher in men with lower bioavailable testosterone levels. The effect of testosterone level was independent of poorer physical performance, suggesting that the effect of testosterone on fall risk may be mediated by other androgen actions.

Accidental Falls↗
PubMed2006

Risk factors for breast cancer in older women: the relative contribution of bone mineral density and other established risk factors.

AIM: To determine the contribution of bone mineral density (BMD) to breast cancer risk relative to other established breast cancer risk factors in postmenopausal women with osteoporosis. METHODS: Data for this analysis comprised those collected from women randomized to placebo in the MORE and CORE trials (N = 2,576). Risk factors measured at baseline included age, family history of breast cancer, estradiol level, body mass index, prior hormone therapy, BMD and vertebral fracture status. Cox proportional hazards regression models were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Over a total of 13,698 woman-years of follow-up, 65 incident breast cancers occurred. In univariate analyses, older age and family history of breast cancer were the strongest predictors of breast cancer risk, associated with a 2.4- and 2.6-fold increase in breast cancer incidence. A higher estradiol level was associated with a 1.9-fold increase in breast cancer incidence. The association between femoral neck BMD and breast cancer incidence was only significant after adjustment for age (P = 0.03). The final multivariable model included age, family history, estradiol, BMD, and the BMD-estradiol interaction since the effect of BMD on breast cancer varied by estradiol level (interaction P-value, 0.04); in those with a lower estradiol level, a higher BMD was associated with a 2.6-fold increased in breast cancer. CONCLUSION: Overall, BMD is a relatively weak predictor of breast cancer risk in these postmenopausal women with osteoporosis, after taking into consideration age, family history and endogenous estradiol level.

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PubMed2006

Effect of raloxifene on the incidence of invasive breast cancer in postmenopausal women with osteoporosis categorized by breast cancer risk.

PURPOSE: To assess the effect of raloxifene, indicated for osteoporosis treatment and prevention, on invasive breast cancer in subgroups of postmenopausal women defined by risk factors for breast cancer. EXPERIMENTAL DESIGN: Data from the 4-year Multiple Outcomes of Raloxifene Evaluation (MORE) trial (N=7,705) and a follow-up study, the 4-year Continuing Outcomes Relevant to Evista (CORE) trial (N=4,011), were analyzed. Prespecified subgroups were defined by age (>or=65 versus<65 years), age at menopause (>or=49 versus<49 years), body mass index (>or=25 versus<25 kg/m2), family history of breast cancer (yes/no), serum estradiol level (5-10 versus<5, >10 versus<5 pmol/L), prior estrogen therapy (yes/no), and bone mass at MORE baseline, and 5-year predicted risk, assessed using the modified Gail model (>or=1.67 versus<1.67%), at CORE baseline. Time-to-first invasive breast cancer was analyzed using Cox proportional hazards models. RESULTS: In the placebo group, older age, higher estradiol level, and a family history of breast cancer were associated with an increased breast cancer risk (P<0.05). Raloxifene therapy was associated with a reduced breast cancer risk in both women at lower and those at higher breast cancer risk. Hazard ratio point estimates were 0.11 to 0.67, corresponding to a 33% to 89% reduction in breast cancer risk with raloxifene versus placebo. The therapy by family history interaction was significant (P=0.04). CONCLUSIONS: Raloxifene therapy was associated with a reduced risk of invasive breast cancer in postmenopausal women irrespective of the presence/absence of risk factors; its effect was greater in women with a family history of breast cancer.

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PubMed2006

Comparison of methods to measure low serum estradiol levels in postmenopausal women.

CONTEXT: Accurate measurement of low serum estradiol (E(2) < 30 pg/ml or < 110 pmol/liter) is needed to study relationships between endogenous E(2) and risks of diseases in older women. OBJECTIVE: The objective of this study was to determine whether an extraction-based (indirect) assay or a non-extraction-based (direct) assay correlates better with mass spectrometry and body mass index (BMI). DESIGN/SETTING: In a pilot study of 40 postmenopausal women, endogenous E(2) measurements from three indirect and four direct assay methods and gas chromatography-tandem mass spectrometry (GC-MS/MS) were compared. A confirmatory study compared an indirect and a direct assay, selected among those in the pilot study, to GC-MS/MS; this study was conducted in 374 postmenopausal women not taking hormone therapy from the Ultra Low-dose TRansdermal estrogen Assessment (ULTRA) trial. MAIN OUTCOMES: Pearson correlation coefficients among E(2) measurements by assay methods and BMI, and their confidence intervals, by bias-corrected bootstrap method, were used. RESULTS: In the pilot study, E(2) by three indirect assays correlated better (P < 0.03) with GC-MS/MS and with BMI than measurements by four direct assays. In the confirmatory study, the indirect assay correlated better (P < 0.01) with GC-MS/MS and BMI than the direct assay. Measurements by the indirect and direct assays were overestimated, but deviations in direct assay measurements were less precise. Mean E(2) by the indirect and direct assays were higher (by 14 and 68%, respectively) and less reproducible than by GC-MS/MS. CONCLUSION: Until mass spectrometry is practical for wide use, extraction-based indirect assays may be preferable for measuring low postmenopausal serum E(2).

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PubMed2006

Renal function and heart failure risk in older black and white individuals: the Health, Aging, and Body Composition Study.

BACKGROUND: Chronic kidney disease is a risk factor for heart failure, an association that may be particularly important in blacks who are disproportionately affected by both processes. Our objective was to determine whether the association of chronic kidney disease with incident heart failure differs between blacks and whites. METHODS: The study population comprised participants in the Health, Aging, and Body Composition Study without a diagnosis of heart failure (1124 black and 1676 white community-dwelling older persons). The main predictors were quintiles of cystatin C and creatinine concentrations and estimated glomerular filtration rate. The main outcome measure was incident heart failure. RESULTS: Over a mean 5.7 years, 200 participants developed heart failure. High concentrations of cystatin C and low estimated glomerular filtration rate were each associated with heart failure, but the magnitude was greater for blacks than for whites (cystatin C concentration: adjusted hazard ratio for quintile 5 [> or =1.18 mg/dL] vs quintile 1 [<0.84 mg/dL] was 3.0 [95% confidence interval 1.4-6.5] in blacks and 1.4 [95% confidence interval, 0.8-2.5] in whites; estimated glomerular filtration rate: adjusted hazard ratio for quintile 5 (<59.2 mL/min) vs quintile 1 (>86.7 mL/min) was 2.7 [95% confidence interval, 1.4-4.9] in blacks and 1.8 [95% confidence interval, 0.9-3.6] in whites). For cystatin C, this association was observed at more modest decrements in kidney function among blacks as well. The population attributable risk of heart failure was 47% for blacks with moderate or high concentrations of cystatin C (> or =0.94 mg/dL) (56% prevalence) but only 5% among whites (64% prevalence). CONCLUSION: The association of kidney dysfunction with heart failure appears stronger in blacks than for whites, particularly when cystatin C is used to measure kidney function.

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PubMed2006

Impact of seafood and fruit consumption on bone mineral density.

OBJECTIVES: Over the past decade, dietary choices and nutrition have proven to be major modulators of bone mineral density (BMD) in men and women. We investigated environmental determinants, specifically dietary habits, of BMD by using multiple regression models in a rural Chinese population. METHODS: BMDs were measured at the hip and total body in 5848 men and 6207 women, aged 25-64. Dietary and supplemental intakes were assessed by a simple, one-page questionnaire tailored to collect nutritional information from large rural populations. Another questionnaire was used to collect information on the subjects' age, disease history, smoking, alcohol consumption, physical activity as well as women's menstrual status and reproductive history. Multiple regression models were used to assess the relationships among dietary variables and BMD, after adjusting for age, BMI (body mass index), weight, occupation, smoking status, and alcohol consumption. RESULTS: Increasing seafood consumption was significantly associated with greater BMD in women (p<0.001), especially those consuming more than 250 g per week of seafood. One thousand and three hundred and twenty-four men and 1479 women consumed >250 g of fruit per week. Higher fruit intake was found to be significantly associated with higher BMD in both sexes (p<0.05). High vegetable consumption, however, did not positively impact BMD. CONCLUSIONS: This study with its large population size has identified preventive measures, as well as some risk factors, involved in bone loss and osteoporosis. Our results highlight the importance of several dietary variables as significant determinants of BMD. It also emphasizes the role of dietary intake in general and shows that specific foods, such as fruits and seafood, can positively impact BMD.

Absorptiometry, Photon↗
PubMed2006

The effects of organic nitrates on osteoporosis: a randomized controlled trial [ISRCTN94484747].

BACKGROUND: Osteoporotic fractures are common and are associated with increased morbidity, mortality and health care costs. The most effective way to moderate increases in health care costs and the sickness and premature death associated with osteoporotic fractures, is to prevent osteoporosis. Several lines of evidence suggest that nitrates, drugs typically prescribed for the treatment of angina, may be effective in preventing postmenopausal osteoporosis. METHODS: We have designed a multicentre randomized controlled trial to determine the effects of nitrates on bone. The trial consists of two studies. The objective of the first study is to determine whether isosorbide mononitrate at 20 mg/day or nitroglycerin ointment at 15 mg/day leads to fewer headaches. The nitrate that is best tolerated will be used in a second study with one main objective: To determine if postmenopausal women with a T-score at the lumbar spine (L1 to L4) between 0 and -2.0 randomized to two years of treatment with intermittent nitrates have a greater increase in spine bone mineral density as compared to women randomized to placebo. We hypothesize that: 1. Women will report fewer headaches when they are randomized to intermittent nitroglycerin ointment at 15 mg/day compared to intermittent oral isosorbide mononitrate at 20 mg/day, and, 2. After two years, women randomized to intermittent nitrates will have a greater percent increase in lumbar spine bone mineral density compared with women randomized to placebo. DISCUSSION: We have completed our pilot study and found that transdermal nitroglycerin was associated with fewer headaches than oral isosorbide mononitrate. We are currently recruiting patients for our second main study.

Journal Article↗
PubMed2006

Thiazolidinedione use and bone loss in older diabetic adults.

CONTEXT: Activation of peroxisome proliferator-activated receptor-gamma by thiazolidinediones (TZDs) results in lower bone mass in mice. OBJECTIVE: The objective of the study was to determine whether TZD use is associated with changes in bone mineral density (BMD) in older adults with type 2 diabetes. DESIGN: We analyzed 4-yr follow-up data from the Health, Aging, and Body Composition observational study. SETTING: The study was conducted in a general community. PATIENTS: White and black, physically able men and women, aged 70-79 yr at baseline with diabetes defined by self-report, use of hypoglycemic medication, elevated fasting glucose (>/=126 mg/dl), or elevated 2-h glucose tolerance test (>/=200 mg/dl) participated in the study. MAIN OUTCOME MEASURES: Whole-body, lumbar spine (derived from whole body), and hip BMD were measured by dual-energy x-ray absorptiometry at 2-yr intervals. RESULTS: Of 666 diabetic participants, 69 reported TZD use at an annual visit, including troglitazone (n = 22), pioglitazone (n = 30), and/or rosiglitazone (n = 31). Those with TZD use had higher baseline hemoglobin A(1c) and less weight loss over 4 yr but similar baseline BMD and weight than others with diabetes. In repeated-measures models adjusted for potential confounders associated with TZD use and BMD, each year of TZD use was associated with greater bone loss at the whole body [additional loss of -0.61% per year; 95% confidence interval (CI) -1.02, -0.21% per year], lumbar spine (-1.23% per year; 95% CI -2.06, -0.40% per year), and trochanter (-0.65% per year; 95% CI -1.18, -0.12% per year) in women, but not men, with diabetes. CONCLUSION: These observational results suggest that TZDs may cause bone loss in older women. These results need to be tested in a randomized trial.

Absorptiometry, Photon↗
PubMed2006

Association of endothelial nitric oxide synthase genotypes with bone mineral density, bone loss, hip structure, and risk of fracture in older women: the SOF study.

Nitric oxide (NO) is an important bone-signaling molecule. We examined the associations between the Glu298Asp polymorphism of NOS3, indices of bone strength, and the incidence of fracture among 6691 women aged 65 years and older enrolled in the Study of Osteoporotic Fractures. Calcaneal BMD was measured at an initial exam and after an average of 5.9 years of follow-up. Hip BMD was measured at an initial exam and after 3.7 years of follow-up. Baseline spine BMD and hip structural parameters were measured. Incident hip fractures were confirmed by review of radiographic reports; follow-up was greater than 98% complete. Incident vertebral fractures were defined by morphometry using lateral spine radiography at baseline and an average of 3.7 years later. The frequencies of the NOS3 Glu298Asp genotypes were Glu/Glu=46.2%, Glu/Asp=42.7%, and Asp/Asp=11.1%. There were no significant associations between NOS3 genotypes and initial calcaneal BMD, hip BMD, or rate of change in hip or calcaneal BMD. None of the hip structural parameters differed substantially by genotype. NOS3 genotype was not significantly associated with either incident or prevalent radiographic vertebral fractures. Women with the heterozygous Glu/Asp genotype had a borderline statistically significantly lower rate of hip fracture than either the Glu/Glu genotype (HR=0.87, 95% CI: 0.74, 1.01) or the Asp/Asp genotype (HR=0.78, 95% CI: 0.62, 0.98). In conclusion, the Glu298Asp polymorphism does not contribute substantially or consistently to indices of bone strength in this sample of older white women, although our findings suggest allelic variation at the NOS3 locus maybe associated with hip fracture risk. Confirmation of these findings is needed in other populations and with additional markers within and flanking the NOS3 gene region.

Age Factors↗
PubMed2006

Calcium plus vitamin D supplementation and the risk of fractures.

BACKGROUND: The efficacy of calcium with vitamin D supplementation for preventing hip and other fractures in healthy postmenopausal women remains equivocal. METHODS: We recruited 36,282 postmenopausal women, 50 to 79 years of age, who were already enrolled in a Women's Health Initiative (WHI) clinical trial. We randomly assigned participants to receive 1000 mg of elemental [corrected] calcium as calcium carbonate with 400 IU of vitamin D3 daily or placebo. Fractures were ascertained for an average follow-up period of 7.0 years. Bone density was measured at three WHI centers. RESULTS: Hip bone density was 1.06 percent higher in the calcium plus vitamin D group than in the placebo group (P<0.01). Intention-to-treat analysis indicated that participants receiving calcium plus vitamin D supplementation had a hazard ratio of 0.88 for hip fracture (95 percent confidence interval, 0.72 to 1.08), 0.90 for clinical spine fracture (0.74 to 1.10), and 0.96 for total fractures (0.91 to 1.02). The risk of renal calculi increased with calcium plus vitamin D (hazard ratio, 1.17; 95 percent confidence interval, 1.02 to 1.34). Censoring data from women when they ceased to adhere to the study medication reduced the hazard ratio for hip fracture to 0.71 (95 percent confidence interval, 0.52 to 0.97). Effects did not vary significantly according to prerandomization serum vitamin D levels. CONCLUSIONS: Among healthy postmenopausal women, calcium with vitamin D supplementation resulted in a small but significant improvement in hip bone density, did not significantly reduce hip fracture, and increased the risk of kidney stones. (ClinicalTrials.gov number, NCT00000611.).

Aged↗
PubMed2006

Comparing a supine radiologic versus standing clinical measurement of kyphosis in older women: the Fracture Intervention Trial.

STUDY DESIGN: A study of agreement between different measures of kyphosis, a clinical standing measure (Debrunner kyphometer; Protek AG, Bern, Switzerland) versus a supine radiologic measure (Cobb angle). OBJECTIVES: To determine whether a supine radiologic measure of kyphosis in older women is a reasonable estimate of clinical kyphosis determined in the standing position, and to investigate a computerized assessment of the Cobb angle. SUMMARY OF BACKGROUND DATA: Few studies have investigated kyphosis measurement agreement involving older adults. METHODS: Using data from the Fracture Intervention Trial, we randomly selected 120 women, aged 55-80 years, who had a Debrunner kyphometer measure of kyphosis and supine lateral spine radiographs from which we measured the Cobb angle (either manually or by digitization). We calculated the intraclass correlation coefficient (ICC) from repeated measures analysis of variance to assess the agreement among the: (1) manual Cobb angle and Debrunner kyphometer, (2) digitized Cobb angle and Debrunner kyphometer, and (3) manual and digitized Cobb angle. RESULTS: The mean of both the manual and digitized Cobb angle was 45 degrees (range 18 degrees-83 degrees), and the mean Debrunner kyphometer reading was 48 degrees (range 17 degrees-83 degrees). The ICC between either of the 2 measures of the Cobb angle and Debrunner measurement was 0.68, indicating reasonable agreement. The ICC between the manual and digitized Cobb angle was 0.99, indicating excellent agreement. CONCLUSIONS: There is reasonable agreement between a supine radiologic and standing clinical measurement of kyphosis in older women.

Aged↗
PubMed2006

Adipocytokines and incident diabetes mellitus in older adults: the independent effect of plasminogen activator inhibitor 1.

BACKGROUND: Adipose tissue produces "adipocytokines" of uncertain clinical significance. METHODS: We analyzed the relationships among adiposity, adipocytokines, glycemia, and incident diabetes mellitus in 2356 white and black adults aged 70 to 79 years in the Health, Aging, and Body Composition Study who did not have diabetes at baseline. We measured the levels of adipocytokines adiponectin, leptin, interleukin 6, tumor necrosis factor alpha, and plasminogen activator inhibitor 1. Regional fat area was determined by means of computed tomography. New diabetes was defined as a self-reported diagnosis of diabetes or as a fasting plasma glucose level of 126 mg/dL or greater (>/=7.0 mmol/L) at the second, fourth, or sixth annual examination. RESULTS: A total of 143 participants (14.1 cases per 1000 person-years) developed diabetes across 5 years. Visceral fat area (odds ratio [OR], 1.33; 95% confidence interval [CI], 1.10-1.60 per standard deviation increase) and body mass index (white individuals: OR, 1.65; 95% CI, 1.26-2.15 per standard deviation increase; black individuals: OR, 1.22; 95% CI, 0.99-1.51 per standard deviation increase) independently predicted incident diabetes. Adiponectin, leptin, and plasminogen activator inhibitor 1 attenuated the relationship between adiposity and diabetes. After controlling for body mass index, visceral fat, fasting glucose, fasting insulin, high-density lipoprotein cholesterol, triglycerides, and hypertension at baseline, plasminogen activator inhibitor 1 was the only adipocytokine independently associated with increased odds of diabetes (OR, 1.35; 95% CI, 1.01-1.81). Fasting glucose level at baseline remained a strong predictor of incident diabetes, whereas associations with body mass index and visceral fat were attenuated. CONCLUSIONS: Adipocytokines and glycemia partially account for the relationship between adiposity and risk of type 2 diabetes due to adiposity. Plasminogen activator inhibitor 1 may be a useful predictor of diabetes in addition to measurements of body fat.

Adiponectin↗
PubMed2006

Endogenous sex hormones, breast cancer risk, and tamoxifen response: an ancillary study in the NSABP Breast Cancer Prevention Trial (P-1).

BACKGROUND: Prospective studies have shown an association between increased serum levels of estradiol and testosterone and breast cancer risk in postmenopausal women. Raloxifene has been shown to reduce breast cancer risk more in women with high estradiol levels than in those with lower levels. The purpose of this study was to determine whether sex hormone levels were associated with breast cancer risk and with response to tamoxifen in a high-risk population. METHODS: Using a case-cohort design, we studied 135 women with postmenopausal breast cancer and 275 postmenopausal women without breast cancer who were enrolled in the National Surgical Adjuvant Breast and Bowel Project Cancer Prevention Trial (P-1) and who had been treated with tamoxifen or placebo for 69 months. We measured estradiol, testosterone, and sex hormone-binding globulin by using radioimmunoassay in baseline plasma samples. Relative risks (RRs) and 95% confidence intervals (CIs) for invasive breast cancer were estimated for each quartile of sex hormone level using Cox proportional hazards models. All statistical tests were two-sided. RESULTS: Median plasma levels of estradiol, testosterone, and sex hormone-binding globulin were similar between the case and cohort groups. The relative risk of breast cancer for women in the placebo group was not associated with sex hormone levels (risk of estrogen receptor-positive breast cancer in women by quartile of estradiol: Q1 [lowest], RR = 1.0; Q2, RR = 1.16, 95% CI = 0.49 to 2.7; Q3, RR = 1.08, 95% CI = 0.45 to 2.61; and Q4, RR = 1.29, 95% CI = 0.59 to 2.82). The reduced risk of invasive breast cancer in tamoxifen-treated women compared with placebo-treated women was not associated with sex hormone levels. CONCLUSIONS: These data do not support the use of endogenous sex hormone levels to identify women who are at particularly high risk of breast cancer and who are most likely to benefit from chemoprevention with tamoxifen.

Aged↗
PubMed2006

Self-reported sleep and nap habits and risk of falls and fractures in older women: the study of osteoporotic fractures.

OBJECTIVES: To test the association between self-reported sleep and nap habits and risk of falls and fractures in a large cohort of older women. DESIGN: Study of Osteoporotic Fractures prospective cohort study. SETTING: Clinical centers in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela Valley, near Pittsburgh, Pennsylvania. PARTICIPANTS: Eight thousand one hundred one community-dwelling Caucasian women aged 69 and older (mean 77.0). MEASUREMENTS: Sleep and nap habits were assessed using a questionnaire at the fourth clinic visit (1993/94). Fall frequency during the subsequent year was ascertained using tri-annual questionnaire. Incident hip and nonspinal fractures during 6 years of follow-up were confirmed using radiographic reports. RESULTS: Five hundred fifty-three women suffered hip fractures, and 1,938 suffered nonspinal fractures. In multivariate models, women who reported napping daily had significantly higher odds of suffering two or more falls during the subsequent year (odds ratio=1.32, 95% confidence interval (CI)=1.03-1.69) and were more likely to suffer a hip fracture (hazard ratio (HR)=1.33, 95% CI=0.99-1.78) than women who did not nap daily. Those sleeping at least 10 hours per 24 hours had a higher risk of nonspinal fracture than (HR=1.26, 95% CI=1.00-1.58) and a similar but nonsignificant increased risk of hip fracture to (HR=1.43, 95% CI=0.95-2.15) those who reported sleeping between 8 and 9 hours. CONCLUSION: Self-reported long sleep and daily napping are associated with greater risk of falls and fractures in older women. Interventions to improve sleep may reduce their risk of falls and fractures. Future research is needed to determine whether specific sleep disorders contribute to these relationships.

Accidental Falls↗