The Relationship between Psychological Distress and Physical Frailty in Japanese Community-Dwelling Older Adults: A Cross-Sectional Study

Background: Older adults’ mental health and physical frailty have been a frequent research focus, but few studies have investigated the relationship between them. Objectives: To investigate the association between mental health and physical frailty in community-dwelling older Japanese people. Design: Cross-sectional study from the Itoshima Frail Study. Setting: Itoshima City, Fukuoka, Japan. Participants: A total of 919 community-dwelling older individuals aged 65–75 years. Measurements: Physical frailty was measured based on five criteria proposed by the Fried scale, and the subjects were classified into three groups: robust, pre-frailty, and frailty. Psychological distress was used to assess the subjects’ mental health, with the Kessler 6-Item Psychological Distress Scale (K6) score; the subjects were divided into three groups based on their K6 score: 0–1, 2–4, and ≥5. Psychological distress was defined by K6 score ≥5. Ordinal logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (CIs) between the psychological distress and physical frailty status. Results: Psychological distress was identified in 190 subjects (20.7%). Forty-six subjects (5.0%) presented with physical frailty, and 24 subjects (2.6%) had both psychological distress and physical frailty. With the increase in the K6 score, more subjects had pre-frailty and physical frailty (p<0.001). Significant positive associations were observed between psychological distress and the risks of pre-frailty (OR 2.94, 95%CI: 1.95–4.43) and frailty (OR 10.71, 95%CI: 4.68–24.51), even in a multivariable-adjusted analysis. In a subgroup analysis of components of frailty, one-point increment in K6 score was associated with higher odds of shrinking and fatigue. Conclusion: A severe psychological distress was associated with increased risks of physical frailty and the frailty sub-items of shrinking and fatigue in community-dwelling older Japanese adults.