Multi-dimensional social frailty index for predicting disability and mortality in community-dwelling older adults: JAGES cohort

BACKGROUND AND OBJECTIVES: We explored the association between a constructed multi-dimensional social frailty index and incidence of disability and all-cause mortality among community-dwelling older adults, examining its prognostic validity. RESEARCH DESIGN AND METHODS: We obtained data from the 2016 Japan Gerontological Evaluation Study (JAGES), surveying community-dwelling individuals aged ≥65 years, not certified as requiring long-term care, at baseline. The analytical sample comprised 73,472 participants (mean age, 73.7 years; 53.4% women) from 18 municipalities across 10 prefectures in Japan. The social frailty index comprised seven items across four domains: general resources (subjective financial conditions), social resources (living arrangements; social networks [visiting friends]), social behavior/activities (social participation; decreased frequency of going out), and basic social needs fulfillment (emotional social support; social cohesion [community attachment]). Incident disability and all-cause mortality were recorded over a mean 3.5-year follow-up. Associations were examined using Cox proportional hazards models adjusted for demographics, health status, and physical, cognitive, and depressive symptoms. RESULTS: Participants were classified as socially non-frail (51.6%), socially pre-frail (39.5%), and socially frail (9.0%). Higher social frailty scores were significantly associated with increased risk of disability and mortality. In the demographics and health status-adjusted model, incident disability hazard ratios were 1.41 for social pre-frailty and 1.77 for social frailty, whereas corresponding mortality hazard ratios were 1.35 and 1.65, respectively (all P < 0.001). DISCUSSION: The multi-dimensional social frailty index demonstrated robust prognostic validity for adverse health outcomes. IMPLICATIONS: Integrating social dimensions into frailty assessments may facilitate early interventions, inform policy development, and improve health maintenance in aging populations.