Structured exercise, cognitive-social engagement, and cognitive impairment-free life expectancy across four longitudinal aging cohorts.

INTRODUCTION

Whether cognitive-social engagement can compensate for insufficient structured exercise in cognitive aging remains unclear.

METHODS

We harmonized repeated data from four aging cohorts across Asia, North America, and Europe. Structured exercise and cognitive-social engagement were cross-classified at each wave into low-low (LL), high exercise-low engagement (HL), low exercise-high engagement (LH), and high-high (HH). Cohort-specific Cox models and multistate life tables estimated incident cognitive impairment and cognitive impairment-free life expectancy.

RESULTS

Cognitive impairment-free life expectancy from age 50 was 17.5, 23.2, 20.1, and 24.7 years for the low exercise + low cognitive-social engagement (LL), high exercise + low cognitive-social engagement (HL), low exercise + high cognitive-social engagement (LH), and high exercise + high cognitive-social engagement (HH) groups, respectively.

DISCUSSION: Structured exercise and cognitive-social engagement showed combined, non-interchangeable benefits for cognitive aging. These findings support integrated lifestyle strategies for dementia prevention across diverse aging populations, health systems, and prevention settings worldwide.