Association of overtime work hours with various stress responses in 59,021 Japanese workers: Retrospective cross-sectional study

This study aims to clarify the relationships between length of overtime work and various stress responses using large-scale cross-sectional data of Japanese workers. This study’s participants are 59,021 Japanese workers in 117 companies. Data was collected by self-reporting questionnaire. The Brief Job Stress Questionnaire was used to measure stress responses on six scales (i.e. “lack of vigor”, “irritability”, “fatigue”, “anxiety”, “depression”, and “somatic responses”). Length of overtime work hours were classified as 0–20, 21–30, 31–40, 41–50, 51–60, 61–70, 71–80, and >80 hours/month. Multiple linear regression analyses were used to examine the association of stress responses with overtime while adjusting all possible confounders. In result, workers with longer overtime showed significantly higher “irritability”, “fatigue”, “anxiety”, “depression”, and “somatic responses” for both genders (p-for-trend