Physical frailty predicts cognitive decline among community-dwelling older Japanese women: A prospective cohort study from the Otassha study

Abstract

Background: Physical frailty and cognitive decline are common issues in geriatrics within an aging society, yet the association between them remains controversial. This study aims to evaluate the association between physical frailty and cognitive decline among community-dwelling older Japanese women.

Methods: A prospective cohort study was conducted in an urban area of Tokyo, Japan, involving community-dwelling older adults 65 years or older. Physical frailty was evaluated using the Japanese version of the Cardiovascular Health Study criteria, consisting of five components: shrinking, weakness, exhaustion, slowness, and low activity. Participants were classified as robust, pre-frail, or frail based on the presence of one or more criteria. Cognitive decline was defined as at least a three-point decrease in the Mini-Mental State Examination score from baseline. The association between physical frailty and cognitive decline was examined using binomial logistic regression, adjusting for potential confounders. The analysis yielded multivariable odds ratios (ORs) and 95 % confidence intervals (CIs), with robust participants using as the reference group.

Results: A total of 2,122 individuals participated in the baseline survey, with 805 included in the analysis (mean age: 72.9 ± 5.1 years). At baseline, 363 participants were classified as pre-frail, while 32 were classified as frail. During the two-year follow-up period, 68 participants experienced cognitive decline. The multivariable OR (95 % CI) for frailty, using robust as the reference, was 3.50 (1.13, 10.80). Furthermore, a linear relationship was observed between physical frailty and cognitive decline.

Conclusion: Among older Japanese women, there exists a dose-response relationship between physical frailty status and cognitive decline.

Keywords: Cognitive decline; MMSE; Physical frailty; Prospective cohort study.