Functional limitation and cognitive impairment among 80+ year old Chinese.

Abstract

This study examined functional limitation in relation to cognitive impairment among 80+ year old Chinese. Cognitively-intact adults ≥80 years old (n = 5161) came from the 1998 Chinese Longitudinal Healthy Longevity Survey. Cognitive impairment was assessed by Mini-Mental State Examination. Functional limitation was assessed by Katz activities of daily living (ADLs). Cox regressions were performed to examine the relationship between functional limitation in 1998 and cognitive impairment onset during the follow-up period of 1998-2012. Compared to those without ADLs limitation at baseline, participants with ADLs limitations were 49% more likely to develop cognitive impairment during follow-up. A dose-response relationship was identified - compared to those without ADLs limitation at baseline, those with one, two to five and all six ADLs limitations were 46, 50 and 180% more likely to develop cognitive impairment during follow-up, respectively. Baseline functional limitation strongly predicted cognitive impairment incidence in 80+ year old Chinese.