Community intervention programs prolong the onset of functional disability among older Japanese

Aim: This study examined the effects of a “community-based center” intervention to prevent the onset of functional disability among residents in disaster-affected areas. Methods: We used data from a prospective cohort study conducted from 2010 to 2016 in Iwanuma City, Japan. Participants were community-dwelling independent adults aged ≥65 years. The exposure variable was the experience of using a community-based center. The outcome variable was functional disability onset. The average treatment effect on the treated (ATET) was estimated by adjusting for possible confounders. Additional analysis stratified by sex was conducted considering the sex differences in social participation rates. Results: Among 3794 participants (mean ± SD age = 72.9 ±5.3 years, 46.0% men), 196 (5.2%) used the community-based center, and 849 (22.4%) exhibited disability onset. Of those with functional disabilities, 40 (20.4%) used the community-based center, while 809 (22.5%) did not. The ATET for functional disability onset with community-based center activities across all participants were not significant (ATET: 0.51 years [95% confidence interval [CI] = −0.23; 1.27]). However, the direction of the effect of community-based center activities differed by sex (ATET: −0.14, 95% CI = −2.59; 2.31 for men [n = 18], and 0.66, 95% CI = 0.18; 1.16 for women [n = 178]). Women exhibited a 15.63% (95% CI = 3.58; 27.68) increase in the time until functional disability onset. Conclusions: The use of community-based centers was associated with a longer period without functional disability in women. Geriatr Gerontol Int 2022; 22: 465–470.