Physical Function, Life Expectancy, and Cognitive Impairment in Older Adults: A 12-Year Longitudinal Cohort Study

Preventing dementia is crucial due to its current and projected global prevalence. Older adults with cognitive impairment/dementia have worse physical function than healthy individuals. However, it is important to quantify the association between performance-based physical function and life expectancy. This study aimed to assess how performance-based physical function affects life expectancy in older adults with and without mild cognitive impairment and dementia.

This research includes an observational, longitudinal cohort study design.

This study used data from the National Health and Aging Trends Study (2011-2023), including 15,202 participants aged ≥65 years.

Physical function was measured using the Short Physical Performance Battery and dementia status was based on validated tests and self-reported diagnosis. Data analysis was conducted from October 2023 through February 2024.

At aged 65, women and men with good physical function gained 3.3 years (95% CI, 1.7-4.8) and 2.9 years (95% CI, 1.4-4.4) of cognitive impairment-free life, respectively, compared with those with poor function. Participants also lived longer beyond a mild cognitive impairment (MCI) diagnosis, but not beyond a dementia diagnosis, than those with poor function.

Maintaining good physical function in older adults is associated with increased life expectancy free of MCI or dementia, and may extend life without dementia in persons with MCI. These findings underscore the importance of promoting active aging to mitigate the burden of cognitive decline.