Effects of a short-term, low-frequency occupational participation programme on health-related quality of life in community-dwelling older adults: A multicentre quasi-experimental study

Introduction: Promoting health-related quality of life in community-dwelling older adults is central to occupational therapy practice in super-ageing societies. However, evidence for short-term, low-frequency occupational participation programmes remains limited. Methods: A multicentre, non-randomised within-subject longitudinal study was conducted in Japanese community groups. Participants served as their own controls during a usual activity period, followed by a 3-month intervention comprising three monthly sessions. Primary outcomes were MOS 36-Item Short-Form Health Survey component scores (Physical Component Summary, Mental Component Summary, Role/Social Component Summary), analysed using linear mixed-effects models. Secondary outcomes (Self-Completed Occupational Performance Index, Frenchay Activities Index, Japanese version of the Montreal Cognitive Assessment, Geriatric Depression Scale [15-item version]) were analysed using Friedman tests with Kendall’s W among completers. Results: Among 139 participants (mean age 80.4 years), the Intervention−Usual contrast was significant for Mental Component Summary but not for Physical Component Summary or Role/Social Component Summary. Among completers, Self-Completed Occupational Performance Index and Japanese version of the Montreal Cognitive Assessment showed significant changes over time, whereas Frenchay Activities Index and Geriatric Depression Scale (15-item version) showed no significant change. No adverse events occurred. Conclusion: A brief, low-frequency occupational participation programme may be associated with favourable changes in mental health-related quality of life and occupational participation among community-dwelling older adults. However, the effect size was small and the clinical significance of the observed change remains uncertain. Changes in Japanese version of the Montreal Cognitive Assessment scores were also observed but should not be interpreted as confirmed improvement in cognitive function. Trial Registration: UMIN-CTR, UMIN000055565. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000063305