Risk factors for falls and for serious injuries on falling among older Japanese women in Hawaii

OBJECTIVES: To evaluate if similar constellations of factors underlie the r isks of falls and injuries on falling for Japanese women as reported for pr edominately white populations. DESIGN: A prospective cohort study SETTING: The island of Oahu PARTICIPANTS: The older Japanese women who participated in the Hawaii Osteo porosis Study (mean age = 74 +/- 5 (SD) years). MEASUREMENTS:As outcomes: falls and serious injuries on falling. As predict ors: anthropometric measurements, measurements of neuromuscular performance , activities of daily living (ADLs), past falls, and other suspected risk f actors for falls and serious injuries. RESULTS: In multivariable models, four subject characteristics were positiv ely associated with having a fall (having a fall in the past year (RR = 2.0 (95% CI, 1.5-2.8)), slow chair stands (RR = 1.4 (95% CI, 1.0-1.9), a short height (RR = 1.5 (95% CI, 1.1-2.1)), difficulties with five or more ADLs ( RR = 1.5 (95% CI, 1.1-2.1))). Two subject characteristics were negatively a ssociated with having a fall (ability to perform a full. tandem balance wit h eyes closed (RR = .7 (95% CI, .5-1.0)) and having a long functional reach (RR = .7 (95% CI,.5-1.0))). The RRs represent as nearly as possible compar isons of the upper (or lower) quartile and the remaining quartiles. In mult ivariable models, long times for chair stands (odds ratio (OR) = 3.0 (95% C I, 1.5-6.1)) and a low BMI (OR = 3.1 (95% CI, 1.5-6.4)) were positively ass ociated with having a serious injury among women who had a fall. Among the same women, taking part in an activity they did frequently (OR = .3 (95% CI , .1-.8)) and slow foot reaction times (OR = .3 (95% CI, .1-.8)) were assoc iated negatively with having a serious injury. CONCLUSIONS: The results from this Japanese cohort support the conclusion t hat women at high risk of falling and serious fall injuries can be identifi ed using a questionnaire and simple, performance-based tests of neuromuscul ar function. The risk factors for falling overlapped, but were distinct fro m, those for suffering a serious injury once a fall had occurred.