Abstract

Background: Social activity has long been recognized as an essential component of active aging. However, an overlooked dimension is cross-national comparison within Asia on social activity and its relationship to the functional decline. This study examined functional decline among older Thai and Japanese adults over a two-year period and compared associated social and other factors.

Methods: We collected data from two waves of a longitudinal cohort survey administered in Nakhon Pathom, Thailand and the city of Tosa, Japan, covering community-dwelling adults aged ≥ 65. The data cover basic activities of daily living (ADL), sociodemographic traits, health status, depression, and social activities. A total of 338 Thai and 869 Japanese participants with no functional limitations participated at baseline, and 216 Thai and 480 Japanese  participants completed the follow-up study after two years.

Results: At follow-up, Thai participants reported a higher percentage of functional decline than Japanese participants (22.2% vs. 13.5%). Risk factors  associated with functional decline in Thai participants were increased age, female gender, low economic satisfaction, and low social activity levels. Functional decline among Japanese participants was associated with increased age, low social activity levels, and arthropathy. Low social activity was a strong predictor of decline in ADL, and the association was significant even after adjusting for related factors in Thai and Japanese individuals.

Conclusion: Although there were differences in the variables associated with ADL decline between Thai and Japanese participants, our results support the promotion of social activities for older adults to preserve a healthy functional status.