LAUSR

Supplemental Digital Content is available in the text Given that longer working hours are generally accompanied by higher individual income, long working hours had different effects on workers’ health depending on their economic status. The results of our study suggest that the effects of low income may dominate the potential negative effects of long working hours. Objectives: To investigate the relationship between working hours and the risk of depression according to household income level. Methods: We used the data from the Korea National Health and Nutrition Examination Survey. The information on working hours was obtained from the questionnaire, and depression was assessed by The Patient Health Questionnaire-9. After stratifying by household income level, the risk of depression for long working hour group (more than or equal to 52 hours a week), compared with the 30 to 51 working hour group as a reference, were calculated using multiple logistic regression. Results: It was found that long working hours associated with high risk for depression in the group with the highest income, but not in the group with the lowest income. Conclusions: The relationship between long working hours and the risk of depression varied by household income level.