Cerebral white matter lesions, gait, and the risk of incident falls: a prospective population-based study.

BACKGROUND AND PURPOSE The association between cerebral white matter lesions (WMLs) and the risk of falls in older people is uncertain, with no supporting prospective evidence. We aimed to determine the risk of incident falls associated with WML volume, and the interactions between WML volume, gait, and other sensorimotor factors leading to falls. METHODS We conducted a prospective, population-based study (n=294, mean age 72.3 years, independently mobile). Volumetric MRI, computerized gait measures, and sensorimotor measures of falls risk were obtained at baseline. Incident falls were recorded prospectively over a 12-month period. Using regression modeling, we estimated the risk of incident falls associated with baseline WML volume. RESULTS Increasing baseline WML volume was independently associated with any incident fall (P=0.01) and multiple incident falls (P=0.02). The risk of incident falls was doubled in people with lesion volumes in the highest quintile of its distribution compared with the lowest (adjusted relative risk, 2.32; 95% CI, 1.28-4.14). Greater lesion volume was also associated with poorer gait and greater gait variability (both P<0.001). The effect of WML volume on the risk of falls was magnified in people with poorer quadriceps muscle strength (P=0.03) and greater gait variability (P=0.001). CONCLUSIONS These data provide the first prospective evidence to our knowledge demonstrating that WMLs are strong risk factors for falls in the general older population. WMLs present potential therapeutic targets for interventional trials in falls prevention.