**Background:** Poor sleep quality negatively affects learning, academic performance, and interpersonal relationships among students. Medical students are particularly vulnerable due to high academic demands and stressful professional roles. While global studies report poor sleep quality prevalence ranging from 41% in Iran to 90% in China among medical students, limited evidence exists from Nepal, especially from publicly funded medical colleges. This study aimed to determine the prevalence and correlates of poor sleep quality among undergraduate medical students at a government medical college in Nepal.
**Methods:** A cross-sectional web-based survey was conducted in March 2021 at Maharajgunj Medical Campus, Institute of Medicine, Kathmandu—the largest government medical college in Nepal. Using random sampling proportionate to study year, 250 students were approached from a total of 383 MBBS students. The final sample included 212 participants (response rate 85%). Sleep quality was assessed using the 19-item Pittsburgh Sleep Quality Index (PSQI), with a global score > 5 indicating poor sleep quality. Depression was measured using the Patient Health Questionnaire-9 (PHQ-9; score ≥ 10 considered depressive disorder), and smartphone addiction using the Smartphone Addiction Scale Short Version (SAS-SV; score > 32 considered problematic). Substance use was assessed via WHO ASSIST. Multivariable logistic regression was performed, including variables with p < 0.1 in bivariate analysis. Adjusted odds ratios (AOR) were calculated at 95% CI with p < 0.05 considered significant.
**Key Results:** Among 212 participants (67.9% male, 63.2% Brahmin/Chhetri), 38.2% (81 students) had poor sleep quality. The mean global PSQI score was 5.36 ± 3.3. Female students had a higher proportion of poor sleep quality (44.1%) than males (35.4%). Regarding sleep patterns, 21.2% slept less than 6 hours, 5.1% had sleep latency > 60 minutes, and 79.3% used no sleep medication. Depression was present in 27.8% of participants, 44.8% were smartphone-addicted, 42.0% were current alcohol users, and 26.4% were current smokers. Multivariable logistic regression revealed four significant correlates of poor sleep quality: depression (AOR = 4.5, 95% CI: 1.8–10.8), current alcohol use (AOR = 2.5, 95% CI: 1.2–5.4), poor academic achievement (having failed the previous year's exam) (AOR = 3.4, 95% CI: 1.1–10.9), and being a fourth-year student compared to first-year (AOR = 3.6, 95% CI: 1.1–11.5). Smartphone addiction, smoking, study choice, and self-reported health problems were significant in bivariate analysis but not in the adjusted model.
**Clinical Implications:** The 38.2% prevalence of poor sleep quality among Nepalese medical students is substantial, though lower than the 44.3% reported in a private Nepalese medical college. The strong association with depression (4.5 times higher odds) underscores the bidirectional relationship between sleep and mental health, suggesting that routine screening for both sleep quality and depressive symptoms should be integrated into medical school health services. The elevated risk among fourth-year students (3.6 times higher than first-year) likely reflects the transition from preclinical to clinical training with increased workload, examinations, and hospital rotations. The authors recommend redesigning the fourth-year syllabus to reduce academic load, implementing academic counseling focused on mental health and sleep hygiene, and developing programs to discourage alcohol consumption. Limitations include the cross-sectional design (precluding causal inference), self-report bias, potential non-response bias (particularly regarding substance use), and use of non-validated Nepali language tools, though English-medium education mitigated language concerns.