Association between mental health and duty hours of postgraduate residents in Japan: a nationwide cross-sectional study

The new duty hour (DH) limit for doctors in Japan will begin in 2024, setting the maximum DHs for postgraduate residents at approximately 80 h weekly. To set appropriate limits, understanding the association between DHs and psychological health is necessary. Thus, we assessed the relationship between residents' psychological health and DHs. We conducted a cross-sectional study involving examinees of the General Medicine In-training Examination 2020. Mental health outcomes were measured dichotomously using the Patient Health Questionnaire-2 for depression and Mini-Z 2.0, for burnout, stress, and satisfaction. Weekly DHs were measured in seven categories at 10-h intervals. The prevalence ratios (PRs) between the DH categories were estimated for each outcome. Of the 6045 residents who provided data on DHs and psychological outcomes, 37.3% showed signs of depression, 21.6% experienced burn out, and 39.2% were highly stressed. In contrast, 62.3% were highly satisfied with their training. Proportions of burnout were higher among residents in Category 6 (>= 90 and <100 h; PR 1.36; 95% CI 1.11-1.66) and Category 7 (>= 100 h; PR 1.36; 95% CI 1.10-1.68) compared with residents in Category 3 (>= 60 and < 70 h; reference). The results partially support the weekly 80-h DH limit in terms of resident well-being.

Automated summary

The new duty hour limit for doctors in Japan, set to begin in 2024, will cap work hours at around 80 hours per week for postgraduate residents. To determine appropriate limits, understanding the relationship between work hours and psychological health is necessary. A study found that over one-third of residents exhibited signs of depression, over one-fifth experienced burnout, and nearly 40% were highly stressed. However, the majority of residents reported high satisfaction with their training.