Association between impaired objective alertness and poor subjective health: a study on physicians’ work-style reform surveillance in Japan

Sleep health is recognized as a fundamental component of health and safety in the workplace. Alertness assessed by the psychomotor vigilance test (PVT) is a key dimension of sleep health. Impaired PVT performance is associated with depression and burnout, but its relation to self-rated health (SRH) remains unclear. In this cross-sectional study, 378 physicians (268 men, 110 women) at Juntendo University Hospital completed a questionnaire and a 3-min PVT after duty hours. Participants were dichotomized as "healthy" or "unhealthy" group based on SRH. PVT lapses (reaction time ≥355 ms) and mean reciprocal reaction time (rRT) were categorized into quartiles. Multivariable logistic regression estimated odds ratios (ORs) for poor SRH with covariates including the Karolinska Sleepiness Scale (KSS) and the 20-item Center for Epidemiologic Studies Depression Scale (CES-D ≥20). Compared with the lowest quartile, the highest quartile of lapses showed an adjusted OR for poor SRH of 4.50 (95% CI, 1.68-12.02), and the lowest quartile of mean rRT yielded an OR of 3.76 (1.36-10.37). These associations remained robust after further adjustment for night-shift duration, snoring, caffeine intake, and either KSS or CES-D. PVT-assessed alertness independently predicts physicians' SRH, suggesting its utility for health monitoring among hospital physicians.