Lower body function and mortality in Mexican American elderly people

Background. The purpose of this analysis was to examine the differential im pact of performance-based and self-reported lower body measures on 2-year m ortality in Mexican American elderly persons. Methods. Data employed are from the Hispanic Established Population for Epi demiological Studies of the Elderly, a probability survey of 3050 community -dwelling Mexican Americans aged 65 and older from the five Southwestern st ates interviewed in 1993 and 1994. Of the baseline sample with complete dat a. 198 persons were confirmed deceased 2 years later. A three-task, perform ance-based. lower body function measure consisting of a short walk, balance . and repeated chair stands tests was used. Self-reported lower body functi on was measured by a 4-item Activities of Daily Living (ADL) measure involv ing the lower body. Results. The three-task. lower body function measure was a significant pred ictor of 2-year mortality. The short walk alone was as predictive as the su mmary measure. The predictive ability of both measures was minimally reduce d by the inclusion of the self-reported ADL measure and life-threatening me dical conditions. Finally. the ADL measure was not a significant predictor of mortality with all the other variables in the analysis. Conclusion. Objective measures of lower body function were significant pred icators of mortality in Mexican American elderly persons, as found in the g eneral population. Unlike previous studies, the ADL measure was not an inde pendent predictor of mortality after controlling for the objective measure and other risk factors. Additional research is needed to address why object ive measures of function are such strong predictors of death.