We investigated the contextual effects of community social capital on functional ability among older people with functional disability in Japan, and the cross-level interaction effects between community social capital and individual psychosocial characteristics. We used data from the Japan Gerontological Evaluation Study for 1936 men and 2207 women nested within 320 communities and followed for 46 months. We used objective data for functional ability trajectories derived from the national long-term care-insurance system, and a validated measure of health-related community social capital comprising three components: civic participation, social cohesion, and reciprocity. A multilevel survival analysis with a community-level random intercept showed that in communities with high civic participation, women who actively participated in any community group showed greater functional ability improvement than did women who did not participate (pinteraction = 0.05). In communities with high social cohesion, older men who perceived that their communities' social cohesion was high showed greater functional ability improvement than men who perceived it to be low (pinteraction = 0.02). Community social capital can thus affect functional ability improvements variously, depending on individual psychosocial characteristics and gender. Community interventions aiming to foster social capital should focus on people who are excluded from existing opportunities to participate.
Keywords: Japan; functional disability; multilevel analysis; older people; social capital.