Long‐Term Predictive Value of Locomotive Function for Multifaceted Health‐Related Quality of Life: A Longitudinal Study of Community‐Dwelling Older Japanese Adults

INTRODUCTION: While physical function and health-related quality of life (HRQOL) are recognized as important factors in aging, evidence regarding their long-term associations remains limited. This study investigated whether baseline physical function measures predict HRQOL after 8 years in community-dwelling adults. METHODS: We conducted a longitudinal analysis of data from community health checkups in rural Japan. Of 678 baseline participants (2012-2014), 130 adults (mean age 62.1 ± 7.7 years, 52.3% female) with complete follow-up data were analyzed. Physical function was assessed using the Timed Up & Go Test (TUG), 10-m gait time, grip strength, and back muscle strength. HRQOL was measured using the SF-36 questionnaire. Multivariable linear regression analyses examined associations between baseline physical function and 8-year follow-up HRQOL, adjusting for baseline HRQOL and covariates. RESULTS: Cross-sectional associations at baseline were limited. However, longitudinal analyses revealed robust associations. After adjustment, TUG was significantly associated with follow-up Physical Functioning (B = -3.53, p = 0.021), Role-Physical (B = -11.40, p < 0.001), Social Functioning (B = -6.20, p < 0.001), Role-Emotional (B = -7.69, p < 0.001), and Mental Health (B = -6.28, p < 0.001). The 10-m gait time showed similar associations. Muscle strength measures were primarily associated with Bodily Pain outcomes. CONCLUSIONS: Baseline locomotive measures, particularly TUG and gait speed, independently predict multiple HRQOL domains after 8 years. These simple assessments during routine checkups may identify individuals at risk for long-term HRQOL decline, supporting early preventive interventions.