Showing papers by "Jeff D. Williamson published in 1998"
TL;DR: The results showed that high bodyfatness is an independent predictor of mobility-related disability in older men and women, and high body fatness in old age should be avoided to decrease the risk of disability.
337 citations
TL;DR: Strength testing may help to identify people close to functional thresholds and, thus, at risk of impaired walking, who would benefit most from strengthening exercises, and Muscle strength was positively but not linearly associated with maximum walking speed.
Abstract: Our aim was to study the association of lower limb strength with maximum walking speed in disabled older women and to try to detect the reserve capacity threshold for maximum walking speed and the minimum strength required for walking at a speed of 1.22 m x s(-1), which is required in crossing signaled intersections. The data are from the baseline of Women's Health and Aging Study, a population-based study on causes and course of disability. Altogether, 1,002 disabled women participated in the tests, which took place at their homes. Maximum isometric hip flexion and knee extension forces were measured on both sides using a handheld dynamometer. For analytic purposes, knee extension torque/body mass ratio (KET/BM) was calculated. Maximum walking speed was measured with a stopwatch during a 4-m walk. KET/BM had a significant effect on walking speed after controlling for number of chronic conditions, balance, use of walking aid, joint pain, age, and body height and mass. A total of 42.3% of the variation in maximum walking speed was explained by these variables. The cumulative percentage distribution of KET/BM of those able to attain a maximum walking speed of 1.22 m x s(-1) (n = 148) was flat to the level of 1.1 N x m x kg(-1), after which it turned upward, indicating that the probability of attaining 1.22 m x s(-1) started to increase after that level. By using segmented linear regression analysis, 2.3 N x m x kg(-1) was found to be the cutoff point beyond which an increase in KET/BM did not correspond to an increase in maximum walking speed. Muscle strength was positively but not linearly associated with maximum walking speed. Strength testing may help to identify people close to functional thresholds and, thus, at risk of impaired walking, who would benefit most from strengthening exercises.
199 citations
TL;DR: This work used data from two large longitudinal studies of older adults (ages 65-100) to estimate transition probabilities from one health state to another, and used those probabilities to estimate the mean additional years of healthy life that an older adult of specified age, sex, and health status would experience.
44 citations
TL;DR: Hip fracture is common among elderly community-dwelling women and is associated with difficulty in performing activities of daily living and is significantly more likely to report difficulty performing 11 activities that map into domains of mobility/exercise tolerance, self-care tasks and higher functioning domains.
Abstract: To estimate the prevalence and impact of self-reported hip fracture in elderly women an age-stratified random sample of 3841 community-dwelling women aged 65 years and above were interviewed to determine the occurrence of 13 chronic conditions and difficulty performing 15 tasks Associations were examined using multiple logistic regression analysis The weighted prevalence of hip fracture was 47 per 100 Prevalence increased with increasing age from 29 per 100 in women aged 65-74 years to 126 per 100 in women aged 85 years and above, and was higher in white women than black women Women with hip fracture were significantly more likely to report concomitant Parkinson's disease (age-adjusted odds ratio [aOR] = 28) and stroke (aOR = 18) After adjustment for potential confounding variables, women with hip fracture were significantly more likely to report difficulty performing 11 activities that map into domains of mobility/exercise tolerance, self-care tasks and higher functioning domains Hip fracture is common among elderly community-dwelling women and is associated with difficulty in performing activities of daily living
39 citations