title: Effect of working hours and precarious employment on depressive symptoms in South Korean employees: a longitudinal study.
abstract: OBJECTIVE
  Long working hours and precarious employment are relatively common in South Korea. Since both can impact on mental health, this study examined their independent and combined effects on depressive symptoms of employees.
  
  
  METHODS
  Data were from the Korean Welfare Panel Study (KOWEPS), 2010-2013. A total of 2733 full-time employees without depressive symptoms were analysed. Hierarchical logistic regression models were used to investigate the effect of the number of working hours per week (eg, 35-40 hours, 41-52 hours, 53-68 hours, and >68 hours) and employment status (permanent vs precarious employment) on depressive symptoms, measured using the Center for Epidemiological Studies Depression (CES-D) 11 scale.
  
  
  RESULTS
  Compared with individuals working 35-40 hours/week, employees working above 68 hours (OR 1.57, 95% CI 1.05 to 2.34) had higher odds of depressive symptoms after full adjustment. Similarly, precarious employees (OR 1.34, 95% CI 1.02 to 1.75) showed worse mental health than permanent employees. In the combined effect model, employees in precarious employment who worked above 68 hours/week (OR, 2.03 95% CI 1.08 to 3.83) exhibited the highest odds of depressive symptoms compared with permanent employees working 35 to 40 hours/week.
  
  
  CONCLUSIONS
  Long work hours and precarious employment status were associated with higher odds of depressive symptoms. The findings highlight the importance of monitoring and addressing the vulnerable groups of employees to reduce the mental health burden of economically active individuals.
authors.affiliation: Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea.|Institute of Health Services Research, Yonsei University, Seoul, Republic of Korea.
authors.forename: Woorim
authors.initials: W
authors.lastname: Kim
authors.affiliation: Institute of Health Services Research, Yonsei University, Seoul, Republic of Korea.|Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Eun-Cheol
authors.initials: EC
authors.lastname: Park
authors.affiliation: Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea.|Institute of Health Services Research, Yonsei University, Seoul, Republic of Korea.
authors.forename: Tae-Hoon
authors.initials: TH
authors.lastname: Lee
authors.affiliation: Institute of Health Services Research, Yonsei University, Seoul, Republic of Korea.|Graduate School of Public Heath, Yonsei University, Seoul, Republic of Korea.
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D003863:Depression / Q000453:epidemiology* / Q000209:etiology*; D004651:Employment / Q000523:psychology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology* / Q000523:psychology*; D056910:Republic of Korea / Q000453:epidemiology; D014940:Work Schedule Tolerance / Q000523:psychology*; D055815:Young Adult
keywords: East Asian societies; depressive symptoms; precarious employment; working hours