Late-Life Social Activity and Cognitive Decline in Old Age

TLDR

The study followed 1,138 dementia‑free adults (mean age 79.6) for up to 12 years (average 5.2) and used mixed‑effects models adjusted for demographic, health, and personality factors to show that higher social activity predicts slower cognitive decline. Each one‑point increase in social activity score corresponded to a 47% reduction in the rate of global cognitive decline, with the most active group experiencing a 70% slower decline, and these effects were consistent across all cognitive domains and not driven by baseline impairment. JINS 2011; 17:998–1005.

Abstract

Abstract We examined the association of social activity with cognitive decline in 1138 persons without dementia at baseline with a mean age of 79.6 ( SD = 7.5) who were followed for up to 12 years (mean = 5.2; SD = 2.8). Using mixed models adjusted for age, sex, education, race, social network size, depression, chronic conditions, disability, neuroticism, extraversion, cognitive activity, and physical activity, more social activity was associated with less cognitive decline during average follow-up of 5.2 years ( SD = 2.7). A one point increase in social activity score (range = 1–4.2; mean = 2.6; SD = 0.6) was associated with a 47% decrease in the rate of decline in global cognitive function ( p < .001). The rate of global cognitive decline was reduced by an average of 70% in persons who were frequently socially active (score = 3.33, 90 th percentile) compared to persons who were infrequently socially active (score = 1.83, 10 th percentile). This association was similar across five domains of cognitive function. Sensitivity analyses revealed that individuals with the lowest levels of cognition or with mild cognitive impairment at baseline did not drive this relationship. These results confirm that more socially active older adults experience less cognitive decline in old age. ( JINS , 2011, 17 , 998–1005)