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M C Nevitt

Publications and source records attributed to M C Nevitt.

At least 19 recordsLinked to original sources
PubMed1997

Calcium intake and fracture risk: results from the study of osteoporotic fractures.

The relation between dietary calcium, calcium, and vitamin D supplements and the risk of fractures of the hip (n = 332), ankle (n = 210), proximal humerus (n = 241), wrist (n = 467), and vertebrae (n = 389) was investigated in a cohort study involving 9,704 US white women aged 65 years or older. Baseline assessments took place in 1986-1988 in four US metropolitan areas. Dietary calcium intake was assessed at baseline with a validated food frequency questionnaire. Data on new nonvertebral fractures were collected every 4 months during a mean of 6.6 years of follow-up; identification of new vertebral fractures was based on comparison of baseline and follow-up radiographs of the spine done a mean of 3.7 years apart. Results were adjusted for numerous potential confounders, including weight, physical activity, estrogen use, protein intake, and history of falls, osteoporosis, and fractures. There were no important associations between dietary calcium intake and the risk of any of the fractures studied. Current use of calcium supplements was associated with increased risk of hip (relative risk = 1.5, 95% confidence interval 1.1-2.0) and vertebral (relative risk = 1.4, 95% confidence interval 1.1-1.9) fractures; current use of Tums antacid tablets was associated with increased risk of fractures of the proximal humerus (relative risk = 1.7, 95% confidence interval 1.3-2.4). There was no evidence of a protective effect of vitamin D supplements. Although a true adverse effect of calcium supplements on fracture risk cannot be ruled out, it is more likely that our findings are due to inadequately controlled confounding by indications for use of supplements. In conclusion, this study did not find a substantial beneficial effect of calcium on fracture risk.

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PubMed1997

Correlates of fear of falling and activity limitation among persons with rheumatoid arthritis.

OBJECTIVES: To examine factors associated with fear of falling, activity limitation due to fear of falling, and how persons modified their activities in response to fear of falling, among older persons with rheumatoid arthritis (RA). METHODS: Participants in a panel study of RA who were over age 50 (n = 570) were questioned about whether they experienced fear of falling and whether and how they limited activities due to fear of falling. RESULTS: Fifty percent reported fear of falling, and 38% modified activities due to fear of falling. Correlates of fear of falling included female gender, depressive symptoms, poor physical functioning, minor fall-related injuries, and a greater number of painful joints. Correlates of limiting activities due to fear of falling included worse self-rated health, poor physical functioning, and high painful joint count. Activities commonly affected included stair climbing, walking, and outings. CONCLUSIONS: Fear of falling and limiting activities are common problems for persons with RA. Persons at risk should be targeted for appropriate interventions.

Accidental Falls↗
PubMed1997

Incidence rates of falls among Japanese men and women living in Hawaii.

Japanese people in both Japan and in Hawaii have a lower incidence of hip fractures than white people in Hawaii or on the mainland of the United States. Hip fractures usually occur after a fall, and differing incidence rates of falls might contribute to the observed differences in hip fracture rates. To investigate this possibility we undertook a prospective study of falls among elderly Japanese men and women living in Hawaii using intensive surveillance methods similar to those used in studies of predominantly white populations. For our Japanese participants, the incidence rates of total falls were 139 per 1000 person years for men and 276 per 1000 person years for women. Age adjusted rate ratios of falls for predominantly white populations compared with our Japanese participants ranged from 1.8 to 2.3 for women and from 2.6 to 4.7 for men. The risk of injuries when they did fall, however, was not lower for our Japanese participants than reported for white participants. For our Japanese population, past falls, female gender, and daytime hours were associated with an increased incidence of falls.

Accidental Falls↗
PubMed1997

Bone mineral density and aortic calcification: the Study of Osteoporotic Fractures.

OBJECTIVE: To investigate the relationship between bone mineral density (in the axial and appendicular skeleton) and calcification of the aorta. DESIGN: Cross-sectional study. SETTING: Community-based study. PARTICIPANTS: A total of 2051 women aged 65 years and older enrolled in the Study of Osteoporotic Fractures. MEASUREMENTS: Bone mineral density (BMD) at the hip, spine, calcaneus, proximal and distal radius; calcification of the aorta (AC); demographic and lifestyle variables; dietary history; functional status; blood pressure; anthropomorphic measures. RESULTS: The prevalence of AC increased with age, ranging from 60% at ages 65 to 69 years to 96% at 85 years and older. BMD in women with calcified arterial plaques was lower (P < .001) when compared with those with no plaques, at all sites measured except the lumbar spine. After adjustment for age, BMD at the hip, spine and calcaneus was not associated with the presence of plaques; only a weak association between BMD and AC remained at the distal and proximal radius. The independent correlates of AC were age, smoking status, systolic blood pressure, coffee drinking, central obesity and a history of diabetes or stroke; current estrogen use was protective. CONCLUSIONS: The results of this study indicate that osteopenia and the deposition of calcific plaques in the wall of the aorta are independent processes that occur as women age. They are probably not causally linked.

Age Distribution↗
PubMed1997

Low thyrotropin levels are not associated with bone loss in older women: a prospective study.

The relationship between excess thyroid hormone and bone loss is controversial. To determine whether low TSH levels, indicating excessive thyroid hormone, are associated with low bone mass or accelerated bone loss in older women, we performed a prospective cohort study of 458 women over age 65 yr participating in the multicenter Study of Osteoporotic Fractures. Three hundred and twenty-three women were randomly selected from the entire cohort of 9704; an additional 135 randomly selected thyroid hormone users were studied. Medical history, medication use, and calcaneal bone mineral density (BMD) were assessed at the baseline visit. Serum was collected and stored at -190 C. Hip and spine BMD were measured approximately 2 yr later, and follow-up calcaneal and hip BMD measurements were obtained after mean follow-up periods of 5.7 and 3.5 yr, respectively. TSH levels were determined in baseline serum samples using a third generation chemiluminescent assay. After adjustment for age, weight, previous hyperthyroidism, and use of estrogen, bone loss over 4-6 yr was similar in women with low, normal, or high TSH. For example, femoral neck bone loss was -0.3%/yr (95% confidence interval, -0.8%, 0.3%) among women with low TSH (< or = 0.1 mU/L) and -0.5%/yr (95% confidence interval, -0.7%, -0.3%) in those with normal TSH (0.1-5.5 mU/L). There were no statistically significant differences in baseline bone mass of the calcaneus, spine, or femoral neck or trochanteric hip subregions. Baseline total hip BMD was 6% lower (P = 0.01) in women with low TSH. Similar results were obtained in analyses confined to women not taking estrogens. We found no consistent evidence that low TSH, a sensitive biochemical marker of excess thyroid hormone, was associated with low BMD or accelerated bone loss in older ambulatory women.

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PubMed1997

Bone mineral density and blood flow to the lower extremities: the study of osteoporotic fractures.

This study tests the hypothesis that reduced blood flow to the lower extremities may affect bone remodeling, resulting in a decrease in bone mineral density (BMD). BMD was measured in the axial and appendicular skeleton of 1292 elderly women (mean age, 71 years) enrolled in the Study of Osteoporotic Fractures. The ratio of the posterior tibial and brachial systolic blood pressures, the ankle/arm index, was used as a measure of blood flow to the legs. In the cross-sectional analysis, this index was positively correlated with BMD at the radius, calcaneus, and hip, but not at the spine. A decrease in the index of 2 standard deviations (SD) (as might occur in patients with moderate arterial disease) was associated with a decrease of 3.7% (95% CI, 1.7%, 5.8%) in hip BMD. The effect size at the hip decreased from 3.7 to 1.8% (and was not statistically significant) when adjustment was made for smoking and/or body mass index (BMI). In the prospective analysis, the rate of bone loss at the hip and calcaneus was greater (p < 0.05) among women whose annual decrease in ankle/arm index was more than 1 SD greater than the mean decrease. This increase was independent of estrogen use, smoking, BMI, pattern of fat distribution, history of diabetes, exercise, and ability to walk. The results from this prospective community-based study provide the first evidence that among relatively healthy older women decreased vascular flow in the lower extremities may be associated with an increased rate of bone loss at the hip and calcaneus.

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PubMed1997

Calcium for prevention of osteoporotic fractures in postmenopausal women.

A systematic review of the literature was conducted to assess the effectiveness of calcium supplements and/or dietary calcium for the prevention of osteoporotic fractures in postmenopausal women. Studies were identified by conducting a Medline search using the text words "fracture" and "calcium" for the period 1966 to March 1997 and by reviewing articles known to the authors. Only studies with fracture outcomes were eligible. There were 14 studies of calcium supplements (including 4 randomized trials), 18 studies of dietary calcium and hip fracture (no randomized trials), and 5 studies of dietary calcium and other fracture sites (no randomized trials). The 4 randomized trials of calcium supplements (mean calcium dose: 1050 mg) found relative risk (RR) reductions between 25% and 70%. Meta-analytic techniques for dose-response data were used to investigate and pool the findings of 16 observational studies of dietary calcium and hip fracture. These hip fracture studies were not consistent and heterogeneity of study findings (p = 0.02) was not easily explained by subject characteristics or study design. Pooling study results gave an odds ratio (OR) of 0.96 (95% confidence interval, (CI) 0.93-0.99) per 300 mg/day increase in calcium intake (the equivalent of one glass of milk). This is likely to be an underestimate of calcium's true effect because of inaccurate measurement of dietary calcium in observational studies. This review supports the current clinical and public health policy of recommending increased calcium intake among older women for fracture prevention.

Adult↗
PubMed1997

Aspirin and nonsteroidal antiinflammatory drug use in elderly women: effects on a marker of bone resorption. The Study of Osteoporotic Fractures Research Group.

OBJECTIVE: Epidemiological studies suggest nonsteroidal antiinflammatory drug (NSAID) and aspirin use is associated with a modest increase in bone mineral density of the hip and lumbar spine. The ability of NSAID to block prostaglandin E2 production has been shown to impair osteoclast activity in animal models. To determine if regular use of these compounds inhibits bone resorption, we assessed NSAID or aspirin use and N-telopeptide crosslink excretion in elderly postmenopausal women. METHODS: N-telopeptide crosslink excretion was assessed from a consecutive sample of 499 women from the Study of Osteoporotic Fractures, age > 65 years, who provided a morning urine sample. Questionnaire, examination, and bone mineral density data were obtained at the same visit. RESULTS: In unadjusted models, daily use of NSAID or aspirin was associated with a reduction of 12.5% (95% CI 0.5, 24.5) in N-telopeptide crosslink excretion (p < 0.05). After adjustment for potential confounders, N-telopeptide crosslink excretion was -4.8% (95% CI -24.4, 14.8) in NSAID users and +7.6% (-9.3, 24.5) in aspirin users compared to nonusers. CONCLUSION: Regular use of either NSAID or aspirin by elderly women was not associated with reduction in N-telopeptide crosslink excretion compared to nonusers.

Aged↗
PubMed1996

Randomised trial of effect of alendronate on risk of fracture in women with existing vertebral fractures. Fracture Intervention Trial Research Group.

BACKGROUND: Previous studies have shown that alendronate can increase bone mineral density (BMD) and prevent radiographically defined (morphometric) vertebral fractures. The Fracture Intervention Trial aimed to investigate the effect of alendronate on the risk of morphometric as well as clinically evident fractures in postmenopausal women with low bone mass. METHODS: Women aged 55-81 with low femoral-neck BMD were enrolled in two study groups based on presence or absence of an existing vertebral fracture. Results for women with at least one vertebral fracture at baseline are reported here. 2027 women were randomly assigned placebo (1005) or alendronate (1022) and followed up for 36 months. The dose of alendronate (initially 5 mg daily) was increased (to 10 mg daily) at 24 months, with maintenance of the double blind. Lateral spine radiography was done at baseline and at 24 and 36 months. New vertebral fractures, the primary endpoint, were defined by morphometry as a decrease of 20% (and at least 4 mm) in at least one vertebral height between the baseline and latest follow-up radiograph. Non-spine clinical fractures were confirmed by radiographic reports. New symptomatic vertebral fractures were based on self-report and confirmed by radiography. FINDINGS: Follow-up radiographs were obtained for 1946 women (98% of surviving participants). 78 (8.0%) of women in the alendronate group had one or more new morphometric vertebral fractures compared with 145 (15.0%) in the placebo group (relative risk 0.53 [95% Cl 0.41-0.68]). For clinically apparent vertebral fractures, the corresponding numbers were 23 (2.3%) alendronate and 50 (5.0%) placebo (relative hazard 0.45 [0.27-0.72]). The risk of any clinical fracture, the main secondary endpoint, was lower in the alendronate than in the placebo group (139 [13.6%] vs 183 [18.2%]; relative hazard 0.72 [0.58-0.90]). The relative hazards for hip fracture and wrist fracture for alendronate versus placebo were 0.49 (0.23-0.99) and 0.52 (0.31-0.87). There was no significant difference between the groups in numbers of adverse experiences, including upper-gastrointestinal disorders. INTERPRETATION: We conclude that among women with low bone mass and existing vertebral fractures, alendronate is well tolerated and substantially reduces the frequency of morphometric and clinical vertebral fractures, as well as other clinical fractures.

Aged↗
PubMed1996

Association of estrogen replacement therapy with the risk of osteoarthritis of the hip in elderly white women. Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To determine whether postmenopausal estrogen replacement therapy is associated with a reduced risk of radiographic findings of osteoarthritis (OA) of the hip. DESIGN: Cross-sectional study. SUBJECTS: White women (N = 4366; age, > or = 65 years) who were participants in a cohort study of osteoporotic fractures. MEASUREMENTS AND METHODS: Radiographs of the pelvis that were obtained in all subjects were assessed for radiographic features of OA of the hip on a summary scale of 0 (none) to 4 (severe OA). Postmenopausal estrogen use was assessed by interview. The association of current and past oral estrogen use with OA of the hip was analyzed by using logistic regression, adjusting for potential confounding variables (eg, indicators of osteoporosis and correlates of estrogen use). RESULTS: Five hundred thirty-nine women (12.3%) had mild or greater radiographic findings of OA of the hip in at least 1 hip, and 214 women (4.9%) had moderate to severe findings; 17% and 24% of the women were current and past users of oral estrogen, respectively. Women who were currently using oral estrogen had a significantly reduced risk of any OA of the hip (adjusted odds ratio [OR], 0.62; 95% confidence interval [CI], 0.49-0.86) and moderate to severe manifestation of disease (OR, 0.54; 95% CI, 0.33-0.88). Current users who had taken estrogen for 10 years or longer had a greater reduction in the risk of any OA of the hip (OR, 0.57; 95% CI, 0.40-0.82) compared with that of users for less than 10 years (OR, 0.75; 95% CI, 0.47-1.24). Current estrogen use for 10 years or longer was associated with a nonsignificant trend for a reduced risk of moderate to severe symptomatic disease (OR, 0.59; 95% CI, 0.28-1.29). CONCLUSION: Postmenopausal estrogen replacement therapy may protect against OA of the hip in elderly white women.

Aged↗
PubMed1996

Mortality following fractures in older women. The study of osteoporotic fractures.

BACKGROUND: Most investigators have hypothesized that the increase in mortality following osteoporotic fractures reflects poor underlying health status in addition to the acute effects of the fracture. METHODS: We observed 9704 ambulatory women aged 65 years or older enrolled in the Study of Osteoporotic Fractures. We obtained reports of fractures and deaths every 4 months and reviewed death certificates and hospital discharge summaries. Multivariable proportional hazards models were used to determine the association between fractures and age-adjusted mortality. RESULTS: During a mean follow-up of 5.9 years, 1737 women had nonspine fractures, with a postfracture mortality rate of 3 per 100 woman-years, compared with 1.8 per 100 woman-years in those who did not have fractures (P < .001). After adjusting for other factors associated with mortality, women (n = 361) with fractures of the hip or pelvis had a 2.4-fold (95% confidence interval, 1.7-3.3) increase in mortality. However, only 9 (14%) of the 64 deaths that occurred after hip or pelvic fractures were caused or hastened by the fracture. By contrast, 11 (17%) of these deaths seemed to have been a result of chronic conditions that has contributed to the hip or pelvic fracture, and 44 (69%) of the deaths were not clearly related to the fracture. CONCLUSIONS: Mortality is increased following several types of fractures in older women. Most of the increase following hip and pelvic fractures is due to underlying conditions and probably would not be affected by reductions in the incidence of these fractures.

Aged↗
PubMed1996

Aspirin and NSAID use in older women: effect on bone mineral density and fracture risk. Study of Osteoporotic Fractures Research Group.

Prostaglandin inhibition by aspirin or nonsteroidal anti-inflammatory drug (NSAIDs) may inhibit bone loss and preserve bone mineral density (BMD) in vitro and in animal models. The effect of these agents on BMD and fracture risk in postmenopausal women in unknown. We assessed the risk factors for osteoporosis and the use of aspirin and NSAIDs in 7786 white women over age 65. Axial BMD was measured at the same time, and fractures were prospectively documented over the subsequent 4 years of follow-up. In age-adjusted analyses, daily use of aspirin or NSAIDs was associated with a 2.3-5.8% increase in BMD of the hip and spine. The relationship persisted even after adjustment for weight, a variety of medications, self-reported arthritis, and for radiographic findings of osteoarthritis, but the multiply adjusted increase in BMD was only 1.0-3.1%. Fracture risk was similar among daily users of aspirin and NSAIDs and nonusers. After adjustment for potential confounders, among daily aspirin users the relative risk of hip fracture was 1.1 (95% confidence interval [CI]: 0.7, 1.6), and among daily NSAID users the risk was 0.9 (CI: 0.6, 1.4). Considering all nonspine fractures together, the risk among aspirin users was 1.0 (CI: 0.8. 1.2), and among NSAID users the risk was also 1.0 (CI; 0.8, 1.2). Regular use of aspirin or NSAIDs may have a modest beneficial effect on BMD in postmenopausal women. This effect persists after adjustment for obesity and the presence of osteoarthritis. However, among women who take aspirin or NSAIDs regularly, there is no clinically significant protective effect on the subsequent risk of fractures.

Aged↗
PubMed1996

Predictors of ankle and foot fractures in older women. The Study of Osteoporotic Fractures Research Group.

To determine risk factors for ankle and foot fractures, data collected from 9704 women 65 years of age or older from four areas of the United States were analyzed. Self-reported baseline questionnaires covered areas such as lifestyle factors (physical activity, diet, and smoking habits) and functional impairment (history of fracture, falling, and other diseases). Bone mineral density (BMD) and performance on neuromuscular tests were also measured. During 5.9 years of follow-up, 191 women fractured an ankle and 204 women fractured a foot. Proportional hazard models were used to estimate relative risks. In multivariable models, factors associated with ankle fracture included one or more falls in the year prior to baseline (relative risk [RR] 1.5; 95% confidence interval [CI] 1.1-2.1), greater vigorous physical activity (RR per 2 times/week, 1.2; CI 1.1-1.3), weight gain since age 25 (RR per 20% gain, 1.4; CI 1.2-1.5), self-reported osteoarthritis (RR 0.5; CI 0.3-0.8), a sister's history of hip fracture after age 50 (RR 1.7; CI 1.0-3.0), out of house < or = 1 per week (RR 3.0; CI 1.4-6.6), and low distal radius BMD (RR per -0.1 g/cm2, 1.2; CI 1.0-1.4). Factors associated with foot fracture included insulin-dependent diabetes (RR 2.9; CI 1.2-7.2), use of seizure medications (RR 2.3; CI 1.0-5.7) or of benzodiazepines (RR 1.5; CI 1.1-2.2), history of hyperthyroidism (RR 0.5; CI 0.3-1.0), poor far depth perception (RR 0.7; CI 0.5-1.0), and low distal radius BMD (RR per -0.1 g/cm2, 1.3; CI 1.1-1.5). Ankle and foot fractures have different profiles of risk factors that are largely independent of low bone mass.

Aged↗
PubMed1996

Non-syncopal falls in the elderly in relation to home environments.

Methods of prevention of falls in the home may differ for healthy and frail individuals. We therefore sought to determine whether measures of health and functioning in older persons are more useful in predicting falls at home not involving home hazards (non-environmental falls) than falls at home related to home hazards (environmental falls), and whether these relationships differ among those who fell once and those who fell multiple times during follow-up. Data for this analysis are from a 1-year prospective cohort study of 325 community-dwelling volunteers aged 60-93 years who had fallen during the year before baseline. In general, associations were stronger between poor functional ability and non-environmental falls than between poor functional ability and environmental falls. Independent predictors of non-environmental first falls during follow-up included Parkinson's disease (adjusted odds ratio (AOR) 7.66, 95% confidence interval (95% CI) 1.15-51.1) and being home alone 10 or more hours per day (AOR 2.36, 95% CI 1.20-4.61); independent predictors of environmental first falls during follow-up included arthritis (AOR 2.60, 95% CI 1.32-5.09) and poor depth perception (AOR 0.73, 95% CI 0.59-0.89, for each unit increase in depth perception score). Also, associations between poor function and falls were generally stronger among participants who fell repeatedly than among individuals who fell only once during the follow-up year. In conclusion, poor function predisposes to non-environmental falls at home in older persons and, to a lesser extent, environmental falls in those who fall repeatedly. Certain functional characteristics such as poor depth perception may predispose to environmental falls to a greater extent than do other disabilities.

Accidental Falls↗
PubMed1996

Validity of self-reported rheumatoid arthritis in elderly women.

OBJECTIVE: To determine the validity of a self-reported physician diagnosis of rheumatoid arthritis (RA) in elderly women. METHODS: Women with self-reported RA were contacted and permission requested to contact their physician. Physicians were mailed a questionnaire requesting information on the subject's arthritic condition. Hand radiographs obtained at study entry were read for changes of RA. RESULTS: The self-reported diagnosis of RA could be confirmed in 26 (21%) individuals. CONCLUSION: The positive predictive value of self-reported RA was low in this cohort. Caution needs to be exercised in the use and interpretation of self-report data concerning arthritic conditions in epidemiologic studies.

Aged↗
PubMed1995

Risk factors for hip fracture in white women. Study of Osteoporotic Fractures Research Group.

BACKGROUND: Many risk factors for hip fractures have been suggested but have not been evaluated in a comprehensive prospective study. METHODS: We assessed potential risk factors, including bone mass, in 9516 white women 65 years of age or older who had had no previous hip fracture. We then followed these women at 4-month intervals for an average of 4.1 years to determine the frequency of hip fracture. All reports of hip fractures were validated by review of x-ray films. RESULTS: During the follow-up period, 192 women had first hip fractures not due to motor vehicle accidents. In multivariable age-adjusted analyses, a maternal history of hip fracture doubled the risk of hip fracture (relative risk, 2.0; 95 percent confidence interval, 1.4 to 2.9), and the increase in risk remained significant after adjustment for bone density. Women who had gained weight since the age of 25 had a lower risk. The risk was higher among women who had previous fractures of any type after the age of 50, were tall at the age of 25, rated their own health as fair or poor, had previous hyperthyroidism, had been treated with long-acting benzodiazepines or anticonvulsant drugs, ingested greater amounts of caffeine, or spent four hours a day or less on their feet. Examination findings associated with an increased risk included the inability to rise from a chair without using one's arms, poor depth perception, poor contrast sensitivity, and tachycardia at rest. Low calcaneal bone density was also an independent risk factor. The incidence of hip fracture ranged from 1.1 (95 percent confidence interval, 0.5 to 1.6) per 1,000 woman-years among women with no more than two risk factors and normal calcaneal bone density for their age to 27 (95 percent confidence interval, 20 to 34) per 1,000 woman-years among those with five or more risk factors and bone density in the lowest third for their age. CONCLUSIONS: Women with multiple risk factors and low bone density have an especially high risk of hip fracture. Maintaining body weight, walking for exercise, avoiding long-acting benzodiazepines, minimizing caffeine intake, and treating impaired visual function are among the steps that may decrease the risk.

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