Association between gait speed and bone strength.pdf

REGULAR ARTICLE Association between gait speed and bone strength in community-dwelling postmenopausal Japanese women Takahiko Sakazaki ? Teruhiko Koike ? Yuji Yanagimoto ? Yoshiharu Oshida Received: 5 November 2011 / Accepted: 10 January 2012  The Japanese Society for Hygiene 2012 Abstract Objectives It is unclear whether gait speed can be used to predict bone status or to diagnose osteopenia or osteopo- rosis. The aim of our study was to determine whether the measurement of physical performance predicts bone strength in community-dwelling postmenopausal Japanese women. Methods We measured speed of sound (SOS), weight bearing index (WBI), maximum or usual gait speed, step length of each gait, single leg balance time with or without eyes closed, and grip strength among 1,061 postmenopausal women (mean age ± standard deviation 68 ± 8 years). Results After adjustments for age and body mass index, SOS was associated with maximum or usual gait speed and with step length during maximum speed gait, but not with WBI, grip strength, single-leg balance time with or without eyes closed, or step-length time during usual gait speed. When subjects were divided into quartile groups based on WBI (a marker of lower extremity strength), significant associations between usual or maximum gait speed and SOS were found only in the lowest and second lowest groups (first and second quartiles). Finally, analysis of sensitivity and specificity at various cut-off points of maximum gait speed to predict decreased SOS showed relatively high specificity compared with the corresponding sensitivity among those with low gait speed. Conclusions Maximum gait speed together with WBI may be a useful and specific test to predict bone status in postmenopausal older women. Keywords Weight bearing index  Speed of sound  Gait speed  Postmenopausal women  Physical function Introduction Life expectancy in developed countries was prolonged by approximately 30 years during the twentieth century. The result