Prolonged social isolation and cognitive function in older adults: lack of informal social contact versus formal social activity as the source of social isolation

Abstract

Objectives This study investigates the cognitive function trajectories associated with prolonged social isolation, while distinguishing between a lack of informal social contact and a lack of formal social activity as the source of social isolation. Methods Data from the Korean Longitudinal Study of Ageing spanning 12 years between 2006 and 2018 were analyzed. A lack of frequent informal social contact or formal social activity was used to assess social isolation, and cognitive function was measured by Korean Mini-Mental State Examination. Fixed effects regression models were used to account for unobserved individual-level confounders. Results A prolonged absence of frequent informal social contact was linked to a decline in cognitive function up to the three waves of exposure (b = −2.135), but cognitive function has not declined further since then. A persistent lack of formal social activity was associated with a decline in cognitive function up to the fifth and subsequent waves of exposure (b = −3.073). No gender differences were observed in these relationships. Conclusion Prolonged social isolation, particularly a lack of formal social activity, can pose a significant threat to the cognitive health of older adults.