Falls and cognitive decline in Mexican Americans 75 years and older

Background: Little is known about long-term emotional and cognitive consequences of falls. We examined the association between falls and subsequent cognitive decline, and tested the hypothesis that depression would mediate any falls-cognition association among cognitively intact Hispanic Elders. Methods: We used data from the Hispanic Established Population for the Epidemiological Study of the Elderly to examine change in Mini Mental State Examination (MMSE) scores over the 6-year period according to number of falls. All participants (N=1,119) had MMSE scores >= 21 and complete data on Center for Epidemiologic Studies of Depression Scale, social and demographic factors, medical conditions (diabetes, heart attack, stroke, and hypertension), and hand grip muscle strength. Results: At baseline, participants' mean age was 80.8 years (range, 74-109), mean education was 6.3 years (range, 0-17), and mean MMSE was 25.2 (range, 21-30). Of the 1,119 participants, 15.8% experienced one fall and 14.4% had two or more falls. In mixed model analyses, having two or more falls was associated with greater decline in MMSE score (estimate =-0.81, standard error =0.19, P<0.0001) compared to having no fall, after adjusting for age, sex, marital status, and education. The magnitude of the association decreased (estimate =-0.65, standard error=0.19, P=0.0007) when adjustment was made for high depressive symptoms, suggesting a possible mediating effect of depression on the falls-cognition association. Female sex, high level of education, and high performance in hand grip muscle strength were associated with a slower decline in MMSE scores. Conclusion: Having two or more falls was independently associated with steeper decline in cognition over 6 years, with a possible mediating effect of depression on the falls-cognition association.