Objectives: This study aimed to examine the effectiveness of a walking point project with incentives for increasing walking time, preventing the decline of physical function and worsening depression among older adults. Methods: We used data from the Japan Gerontological Evaluation Study, which included subjects aged ≥65 years who lived in Yokohama City in 2013 and 2016. We obtained information on the subjects' participation in the "Yokohama Walking Point (YWP)," a program launched by Yokohama City in 2014, from the 2016 survey data. We excluded individuals with missing data for sex, age, walking time per day (<30, 30-59, 60-89, or ≥90 min/day), physical function (5 physical function category items on the Kihon Checklist), depression (15-item Geriatric Depression Scale), and participation status in the YWP. We used data from 4,509 eligible respondents. Changes in walking time, physical function, and depression were designated as dependent variables, and participation status in the YWP was designated as the independent variable in the multiple regression analysis with inverse probability of treatment weighting (IPTW), after adjusting for demographic variables, socioeconomic status, health status, and behavior. Results: Among the total subjects, 758 (16.8%) participated in the YWP. The IPTW method showed that participants in the YWP had significantly higher walking times (B=3.61, 95% CI: 1.04, 6.17), less decline in physical function, and less depression (B=-0.13, 95% CI: -0.23, -0.03; B=-0.21, 95% CI: -0.42, -0.01) than those who did not participate in the YWP. Conclusions: Our findings suggest that the YWP, with incentives, effectively increased walking time and prevented worsening of physical function and depression among older adults. The municipality's health point project, based on the number of steps, is a useful population approach for promoting health among older adults.
Keywords: incentives; older adults; propensity scores; walking.