Decline in cognitive and functional skills increases mortality risk in nondemented elderly

Objective: To investigate the relation between rate of decline in cognitive and functional/ physical abilities and risk of death in nondemented elderly. Methods: Data were included from individuals participating in a prospective study of aging and dementia in Medicare recipients, 65 years and older, residing in northern Manhattan. The authors included 878 members of the cohort who had measures of memory, cognitive, language, or functional scores over three study intervals, excluding all participants who were demented or had more than one problem in activity of daily living (ADL) skills at baseline. Participants were classified as showing no decline, slow, medium, or rapid rate of decline, based on the slope of change in cognitive and functional/ physical factors. The authors used survival methods to examine the relation of rate of decline in cognitive and functional performance to subsequent mortality in younger and older nondemented elderly and across three ethnic groups, adjusting for potential confounders. Results: Nondemented elderly with preserved ADL skills who showed rapid rates of decline on measures of visuospatial reasoning/cognitive, language, ADL, and instrumental ADL functions were approximately twice as likely to die as nondemented elderly who showed no decline or slower rates of decline, while rate of decline in memory or in measures of extremity mobility was not related to risk of death. The association of the rate of decline to risk of death was stronger in relatively young ( <= 75 years) than in older participants. Conclusions: Rate of decline in cognitive and functional skills predicts mortality in nondemented elderly.