Long-term impact of a senior volunteer-driven frailty check programme on care dependency and expenditures: a 10-year population-based cohort study in Japan

BACKGROUND: Although volunteer-driven, community-based interventions to prevent long-term care (LTC) dependency have shown promise, long-term evidence of their effectiveness and economic impact remains scarce. We aimed to evaluate the association of a volunteer-driven frailty check (FC) programme with LTC certification and benefit expenditures. METHODS: We conducted a 10-year retrospective, population-based cohort study in a municipality in Japan. Of 59 812 residents aged ≥65 years (2015-2024), FC participants were matched 1:1 with non-participants separately within each year using propensity scores, and the yearly matched sets were pooled for analysis, yielding 2672 participants and 2672 matched controls. Outcomes were incident LTC certification and annual per-capita LTC expenditures, analysed using Cox proportional hazards and generalised linear mixed-effects models. RESULTS: Among 5344 matched individuals (mean age 73.5 ± 4.9 years), 16.8% of participants and 19.8% of controls received LTC certification [hazard ratio 0.85, 95% confidence interval (CI) 0.75-0.97; absolute risk reduction 3.0%; number needed to treat 33]. Annual per-capita LTC expenditures were consistently lower among participants, with the gap widening over time (cost ratio 0.66, 95% CI 0.51-0.84), yielding cumulative savings of ~JPY443 000 per participant over 10 years. Exploratory analyses indicated slower growth in combined medical and LTC expenditures. CONCLUSION: This programme was associated with lower LTC dependency and slower growth in combined medical and long-term care expenditures. Implemented in 106 municipalities in Japan, this volunteer-led, community-based model may offer a low-cost, scalable intervention to promote healthy ageing and sustainability in super-aged societies, with relevance for countries facing population ageing and fiscal constraints.