Sleep Quality and Mental Health of High-Level Esports Competitors: A Cross-Sectional Study

<b>Background:</b> Sleep quality and mental health are important concerns for esports competitors. However, epidemiological data regarding sleep quality and psychological distress among high-level esports players remain limited. <b>Objective:</b> This study aimed to examine sleep quality and mental health status among high-level esports competitors in Japan and to identify factors associated with psychological distress. <b>Methods:</b> This cross-sectional study included 275 competitors (269 males, 3 females, and 3 who did not report sex) participating in the 2023 National Prefectural Esports Championship. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), psychological distress using the Kessler Psychological Distress Scale (K6), and depressive symptoms using the Patient Health Questionnaire-9 (PHQ-9). Multivariable logistic regression analyses were performed to identify associated factors. <b>Results:</b> The response rate was 61.8% (275/445). Poor sleep quality (PSQI > cut-off) was observed in 38.5% of competitors. Based on the K6, 24.4% reported psychological distress above the mild threshold, and 29.5% reported mild or greater depressive symptoms according to the PHQ-9. Overall mental health levels were comparable to those reported in previous studies of general populations. Nighttime esports training was significantly associated with psychological distress (adjusted odds ratio 3.80; 95% confidence interval 1.50-9.64; <i>p</i> = 0.005). <b>Conclusions:</b> More than one-third of Japanese esports competitors experience poor sleep quality, and approximately one-quarter report mild or greater psychological distress. Nighttime esports training may be an important factor associated with mental health among competitors. Further longitudinal studies are warranted to clarify temporal relationships and to examine whether reducing nighttime training is associated with improved mental health outcomes among esports competitors.