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M C Nevitt

Publications and source records attributed to M C Nevitt.

At least 73 records · Page 4Linked to original sources
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.

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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.

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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.

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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.

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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.

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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.

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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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PubMed1995

Is postmenopausal estrogen therapy associated with neuromuscular function or falling in elderly women? Study of Osteoporotic Fractures Research Group.

BACKGROUND: Muscle strength declines with advancing age; the causes of this are uncertain. In women, strength begins to decline around the time of menopause, suggesting that hormonal changes might influence strength. To determine the effect of postmenopausal estrogen use on muscle strength, neuromuscular function, and the risk of falling, we examined 9704 participants aged 65 years or more enrolled in the Study of Osteoporotic Fractures. METHODS: We measured hip abductor, triceps extensor, and hand-grip muscle strength, balance, gait speed, and self-reported functional disability. Falls during the first year of follow-up were determined from postcards that participants mailed every 4 months indicating whether they had fallen in the previous 4 months (> 99% complete follow-up). RESULTS: After adjusting for age, medications, medical history, and personal habits, current estrogen users did not differ in a clinically meaningful way from those who had never used estrogen on tests of hip abductor strength (mean difference, 0.15 kg; 95% confidence interval, -0.05 to 0.34 kg), triceps extensor strength (0.005 kg; -0.17 to 0.18 kg), or grip strength (0.30 kg; 0.00 to 0.59 kg). Gait speed, time to stand five times from a chair, balance, self-reported disability, and incidence of falls (odds ratio, 1.12; 95% confidence interval, 0.87 to 1.44) also did not differ between current users and never users. In addition, current users were similar to past users on all measures. CONCLUSION: We found no evidence that postmenopausal estrogen use has beneficial effects on muscle strength or neuromuscular function or that it reduces the risk of falling.

Accidental Falls↗
PubMed1995

Radiographic osteoarthritis of the hip and bone mineral density. The Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To examine the cross-sectional association between radiographic features of hip osteoarthritis (OA) and bone mineral density (BMD) of the hip, spine, and appendicular skeleton among Caucasian women ages 65 and older who were participating in the Study of Osteoporotic Fractures. METHODS: Pelvis radiographs of 4,855 subjects were assessed for individual radiographic features of hip OA: osteophytes, joint space narrowing, subchondral sclerosis, cysts, and femoral head deformity. Hips were graded on a summary scale of 0 (no OA) to 4 (severe OA) based on the number of radiographic features present. Appendicular BMD was measured in all subjects, and hip and spine BMD in 84% of the group. We used linear regression to examine the association of BMD with hip OA, and to adjust for age, weight, and other determinants of bone mass. RESULTS: Three hundred fifty-one women (7.2%) had mild (grade 2) and 228 (4.7%) had moderate to severe (grade 3-4) radiographic evidence of hip OA. Women with grade 3-4 hip OA had a higher age-adjusted BMD at the femoral neck and Ward's triangle (9-10%; P < 0.0001), trochanter (4%; P < 0.01), lumbar spine (8%; P < 0.0001), and distal radius and calcaneus (5%; P < 0.0001 [for each comparison]) compared with those with grade 0-1 OA in the worse hip. Elevations in BMD were greatest in the femoral neck of hips with OA, in women with bilateral hip OA, and in women with hip osteophytes. These findings were essentially unchanged by adjustment for determinants of bone mass. CONCLUSION: Elderly Caucasian women with moderate to severe radiographic hip OA had higher BMD in the hip, spine, and appendicular skeleton than did women without hip OA. Our findings are consistent with a role of elevated BMD in the pathogenesis of hip OA.

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PubMed1995

Rheumatoid arthritis and bone mineral density in elderly women. The Study of Osteoporotic Fractures Research Group.

Previous studies have suggested that women with rheumatoid arthritis (RA) have decreased bone mineral density (BMD) in both the appendicular and axial skeleton. The purpose of this investigation was to determine the association of RA and BMD from a community-based sample of ambulatory Caucasian women age 65 and over. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the hip and lumbar spine and by single photon absorptiometry (SPA) at the distal radius and calcaneus. Study subjects included 120 postmenopausal women with RA who were further classified according to corticosteroid use, i.e., never users, current users, and ex-users, and 7966 age-similar controls. Elderly women with RA had a lower age-adjusted bone density of the distal radius, calcaneus, hip, and lumbar spine. Women with RA who were current users of steroids had the lowest BMD at both appendicular sites and at the hip, but those who never used steroids also had a significantly decreased BMD at all sites. The BMD of women with RA who had never used steroids remained significantly decreased at the distal radius, calcaneus, and hip after adjustment for age, BMD determinants, and functional outcomes of RA. Functional outcomes of RA largely accounted for the lower BMD of women who were currently using steroids. Women with RA have lower appendicular and axial bone mass that is not attributable to the use of steroids. Those currently taking steroids have even lower appendicular and axial bone mass that may reflect their poorer functional outcome and is likely to increase the risk of fractures.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1995

Comparison of methods for defining prevalent vertebral deformities: the Study of Osteoporotic Fractures.

Women with vertebral deformities caused by osteoporosis have more back pain and disability and are at higher risk for subsequent vertebral deformities than women without deformities. Despite the importance of vertebral deformities, there has been a great deal of controversy about how to identify or define them. In order to compare methods for defining vertebral deformities, we studied spinal radiographs from women in the Study of Osteoporotic Fractures (SOF), a cohort study of 9704 non-black women over age 65 recruited from population-based listings in four clinical centers. Using radiographs obtained at the baseline exam, we compared five methods for defining vertebral deformities: one based on a semiquantitative reading by a radiologist and four using vertebral morphometry. The semiquantitative method was compared with the other methods in a random sample of 503 films, while the morphometric methods were compared with each other in a larger sample of 9575 films. We tested a system of "triage" in which only those films with evidence of deformity were assessed by morphometry. We compared the relationship between deformity, defined by each method, and a variety of clinical criteria including bone mineral density at the lumbar spine, height loss since age 25, back pain, and incidence of subsequent deformity. Semiquantitative reading and three of the four morphometry-based methods provided similar relationships to clinical criteria. The fourth morphometry method (based on ratios of each vertebral height to the corresponding height at T4) produced significantly weaker relationships for several of the clinical validation criteria. Triage of radiographs rarely resulted in missed deformities and did not reduce the performance of any of the methods. We conclude that use of any of the similar methods, with or without triage, provides a valid approach to defining vertebral deformities.

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PubMed1995

Hip and calcaneal bone loss increase with advancing age: longitudinal results from the study of osteoporotic fractures.

It is uncertain whether or how rapidly elderly women continue to lose bone with advancing age. To determine rates of change in bone mass at the hip and at the calcaneus in elderly women and to compare these rates of change among estrogen users and nonusers, we prospectively measured rates of change in bone mineral density (BMD) at the total hip and its four subregions (mean +/- SD, 3.55 +/- 0.29 years between examinations) and at the calcaneus (mean +/- SD, 5.69 +/- 0.33 years between examinations) in 5689 community-dwelling white women aged 65 years or older at the baseline examination. The rate of decline in total hip BMD steadily increased from 2.5 mg/cm 2/year (95% confidence interval 2.0 to 2.9) in women 67-69 years old to 10.4 mg/cm 2/year in those aged 85 or older (95% confidence interval 8.4 to 12.4). The rate of bone loss also increased with aging at all subregions of the hip and at the calcaneus. The average loss of bone from the total hip is sufficient to increase the risk of hip fracture by 21% per 5 years in women aged 80 years or older. Compared with nonusers, current estrogen users had a 33% lower age-adjusted mean rate of loss at the total hip (2.9 vs 4.3 mg/cm 2/year, p < or = 0.0001) and a 35% lower age-adjusted mean rate of loss at the calcaneus (3.9 vs 6.0 mg/cm 2/year, p < or = 0.0001). The rate of bone loss in the hip and calcaneus steadily increases with advancing age in older women. Estrogen therapy may significantly decrease this loss. Efforts to understand and prevent bone loss should include elderly women.

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PubMed1995

Body weight versus body fat distribution, adiposity, and frame size as predictors of bone density.

Weight is strongly associated with bone mineral density (BMD), but the mechanism of this effect is not well understood. Weight, height, hip-waist ratio, elbow breadth, adiposity, and BMD were measured in 6705 older women participating in the Study of Osteoporotic Fractures. Adiposity was measured by bioelectric impedance and BMD by single-photon (proximal and distal radius and calcaneus) and dual-energy x-ray absorptiometry (lumbar spine and proximal femur). Age-adjusted associations between weight and BMD were robust at all sites (R2 = 5.9-20.4%), but the addition of other anthropometric variables to the model only marginally improved the association. Adiposity explained a substantial fraction of the effect of weight on BMD, particularly at weight-bearing sites (36-62%). On the other hand, weight explained virtually all the variability of adiposity on BMD at weight-bearing sites (81-100%). At the radial measurement sites, adiposity had more substantial independent contributions. Weight did not seem to influence the relationship between BMD and age. In sum, at weight bearing-sites, the preponderance of the effect of weight on BMD is a direct result of mass effects rather than adiposity, whereas at non-weight-bearing sites, adiposity exerts more important effects, potentially mediated by metabolic factors.

Adipose Tissue↗
PubMed1995

Home hazards and falls in the elderly: the role of health and functional status.

OBJECTIVES: This study was undertaken to determine whether vigorous and frail older people who identify environmental hazards in their homes have an increased risk for falls. METHODS: A 1-year prospective study was conducted among 266 female and 59 male community-dwelling volunteers aged 60 to 93 years who had fallen at least once during the previous year. Composite measures of home safety and of frailty were derived using principal components analysis. Participants were divided into vigorous and frail groups, and associations between baseline home safety measures and falls at home over the follow-up year were compared between the two groups. RESULTS: Frail individuals were more than twice as likely as vigorous individuals to fall during follow-up (rate ratio [RR] = 2.24; 95% confidence interval [CI] = 1.54, 3.27). In the study group as a whole, falls were not strongly associated with the presence of home hazards. However, when compared with vigorous older persons living with fewer home hazards, vigorous older persons living with more home hazards were more likely to fall. The increased risk for falls among vigorous elderly was limited to falls where home hazards were present. By contrast, living with more home hazards was not associated with increased likelihood of falls among frail older persons. CONCLUSIONS: While frail older persons experience higher overall fall rates, vigorous older persons should not be overlooked in fall prevention projects.

Accidental Falls↗