Physical Function Changes in Older Adults Living in Temporary Housing after the Great East Japan Earthquake.

Introduction: The aging of the global population presents significant challenges in extending healthy life expectancy, particularly among older adults. The prevalence of musculoskeletal disorders and the growing demand for nursing care are expected to reduce healthy life expectancy. These outcomes are particularly influenced by disasters that cause major environmental changes. This study aimed to clarify the long-term effects on physical function resulting from temporary changes in the living environment of older adults who relocated to temporary housing (TH) following the Great East Japan Earthquake. Methods: This retrospective cohort study included 4,680 residents of Soma City, Fukushima Prefecture, aged ≥64 years, who underwent locomotor function examinations between 2013 and 2022. Participants were categorized into two groups: TH (n = 440) and control (n = 4,240). The primary outcomes were grip strength and one-leg standing time. A growth curve model was used to estimate the longitudinal associations. Results: The mean age- and sex-adjusted one-leg standing time was lower in the TH group than in the control group in 2013 (35.5 seconds vs. 39.3 seconds) and remained lower thereafter. The results showed an association between one-leg standing time and TH experience (intercept estimate: -4.32, 95% confidence interval: -7.49 to -1.16). No differences in grip strength were observed between the groups. Conclusions: These results suggest that long-term support is necessary for evacuees, and it is essential to develop and implement support measures that effectively address muscle weakness and other aspects of physical function.