Abstract
<title>Abstract</title> <p>Background Prefrailty is a transitional, potentially reversible stage between robustness and frailty. Identifying modifiable factors associated with prefrailty is critical for frailty prevention. Although sleep disturbances are associated with frailty, evidence linking subjective sleep quality to prefrailty remains limited, particularly among community-dwelling older adults. Objective To determine whether subjective sleep quality is independently associated with prefrailty among community-dwelling older adults. Methods This cross-sectional study included 110 community-dwelling older adults aged ≥ 65 years who participated in a community-based physical fitness assessment program. Frailty status was assessed using the revised Japanese Cardiovascular Health Study (J-CHS) criteria. Two participants classified as frail were excluded because of the small sample size. The remaining participants were classified as robust (n = 70) or prefrail (n = 40). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Physical, respiratory, and cognitive function were also evaluated. Binary logistic regression analysis identified factors independently associated with prefrailty. Results The prevalence of prefrailty was 36.4%. The mean PSQI score was 7.96 ± 2.29 points, and 86.4% of participants exceeded the cutoff for poor sleep quality. In binary logistic regression analysis, PSQI score was the only factor independently associated with prefrailty (odds ratio [OR] = 1.38, 95% confidence interval [CI]: 1.10–1.72, p = 0.005). Each one-point increase in PSQI score increased the odds of prefrailty by 37.7%. Age, cognitive function, muscle strength, gait speed, balance ability, skeletal muscle mass, and respiratory function were not significantly associated with prefrailty. These findings suggest that subjective sleep quality may identify vulnerability before measurable declines in physical performance. Conclusions Poor subjective sleep quality was independently associated with prefrailty among community-dwelling older adults. Sleep quality may represent an early, modifiable marker of vulnerability preceding measurable declines in physical performance. Incorporating sleep assessment into community-based screening programs may improve early identification of older adults at risk of frailty progression.</p>