Relationship between long working hours and depression: a 3-year longitudinal study of clerical workers.
OBJECTIVE
To clarify how long working hours affect the likelihood of current and future depression.


METHODS
Using data from four repeated measurements collected from 218 clerical workers, four models associating work-related factors to the depressive mood scale were established. The final model was constructed after comparing and testing the goodness-of-fit index using structural equation modeling. Multiple logistic regression analysis was also performed.


RESULTS
The final model showed the best fit (normed fit index = 0.908; goodness-of-fit index = 0.936; root-mean-square error of approximation = 0.018). Its standardized total effect indicated that long working hours affected depression at the time of evaluation and 1 to 3 years later. The odds ratio for depression risk was 14.7 in employees who were not long-hours overworked according to the initial survey but who were long-hours overworked according to the second survey.


CONCLUSIONS
Long working hours increase current and future risks of depression.
Department of Health Informatics, Kyoto University School of Public Health, Sakyo-ku, Kyoto, Japan. amagasa_t@tokyo-kinikai.com
Takashi
T
Amagasa
Takeo
T
Nakayama
D000328:Adult; D003863:Depression / Q000209:etiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D009784:Occupational Diseases / Q000209:etiology*; D011581:Psychological Tests; D011795:Surveys and Questionnaires; D013997:Time Factors; D014940:Work Schedule Tolerance / Q000523:psychology*