Differential effects of employment grade on the association between long working hours and problem drinking

Objective To examine the association between working hours and problem drinking in employees from different employment grades. Methods We used data from a national survey of randomly sampled Taiwanese workers. A total score of 2 or more on the Cut down, Annoyed, Guilty, and Eye-Opener (CAGE) questionnaire was used to identify problem drinkers. Weekly working hours were categorized into five groups: <40, 40, 41-48, 49-59, and >= 60. Employees were classified into three employment grades: managers and professionals, skilled workers, and low-skilled workers. The associations between working hours and problem drinking in employees from different employment grades were examined by logistic regression models. Results In skilled workers, problem drinking was associated with <40 and 41-48 working hours, but not with >48 working hours. In low-skilled workers, problem drinking was most strongly associated with 49-59 working hours. Conclusion The association between working hours and problem drinking was not linear and differed with employment grades.