AIM: This study examined the short-term effects of participation in Kayoi-no-ba - community gathering places for residents to contribute to care prevention with the support of volunteers in Japan - on frailty status during the coronavirus disease 2019 (COVID-19) pandemic, based on a 1-year longitudinal study of older adults. METHODS: Participants (n = 3899) were aged ≥65 years. At baseline, they were classified into four groups, based on their frequency of participation in Kayoi-no-ba before and after the COVID-19 pandemic: the nonparticipation group, the continued participation group, the interrupted participation group and the new participation group. Frailty status, assessed using the modified Kihon Checklist, was the dependent variable. A generalized linear mixed-effects model was used to compare frailty status changes after a 1-year follow up in the four groups. RESULTS: The frailty prevalence at baseline was 30.8% in the nonparticipation group, and 37.2% in the participation group. The frailty prevalence in the participation group was significantly reduced at the 1-year follow up (-3.9 percentage points [95% CI -7.4, -0.5]), compared with that of the nonparticipation group. In subgroup analyses, the frailty prevalence was reduced at the 1-year follow up in the order of continued participation group (-4.5 percentage points [95% CI -8.9, -0.2]), new participation group (-4.0 percentage points [95% CI -12.9, 5.0]), and interrupted participation group (-2.4 percentage points [95% CI -9.1, 4.3]), compared with the nonparticipation group (P = 0.024 for trend). CONCLUSIONS: Even during the COVID-19 pandemic, participation in Kayoi-no-ba was effective in preventing/reducing frailty. Thus, avoiding prolonged nonparticipation in Kayoi-no-ba might be important. Geriatr Gerontol Int 2025
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