title: Work Engagement as a Predictor of Onset of Major Depressive Episode (MDE) among Workers, Independent of Psychological Distress: A 3-Year Prospective Cohort Study.
abstract: OBJECTIVE
  This study investigated work engagement as a baseline predictor of onset of major depressive episode (MDE).
  
  
  METHODS
  The study used a prospective cohort design, conforming to the STROBE checklist. Participants were recruited from the employee population of a private think tank company (N = 4,270), and 1,058 (24.8%) of them completed a baseline survey, of whom 929 were included in this study. Work engagement and psychological distress at baseline were assessed as predictor variables. MDE was measured at baseline and at each of the follow-ups as the outcome, using the web-based, self-administered version of the Japanese WHO-CIDI 3.0 depression section based upon DSM-IV-TR/DSM-5 criteria. Cox discrete-time hazards analyses were conducted to estimate hazard ratios (95% confidence intervals CIs).
  
  
  RESULTS
  Follow-up rates of participants (N = 929) were 78.4%, 67.2%, and 51.6% at 1-, 2-, and 3-year follow-ups, respectively. The association between work engagement at baseline and the onset of MDE was U-shaped. Compared with a group with low work engagement scores, groups with the middle and high scores showed significantly (HR = 0.19, 95% CI = 0.05 to 0.64; p = 0.007) and marginally significantly (HR = 0.48, 95% CI = 0.20 to 1.15, p = 0.099) lower risks of MDE, respectively, over the follow-ups, after adjusting for covariates. The pattern remained the same after additionally adjusting for psychological distress.
  
  
  CONCLUSIONS
  The present study first demonstrated work engagement as an important predictor of the onset of MDE diagnosed according to an internationally standard diagnostic criteria of mental disorders.
authors: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors: Kotaro
authors: K
authors: Imamura
authors: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors: Norito
authors: N
authors: Kawakami
authors: Department of Mental Health, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Japan, Kitakyushu, Japan.
authors: Akiomi
authors: A
authors: Inoue
authors: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors: Akihito
authors: A
authors: Shimazu
authors: Department of Public Health, Kitasato University School of Medicine, Sagamihara, Japan.
authors: Akizumi
authors: A
authors: Tsutsumi
authors: Health Administration and Psychosocial Factor Research Group, National Institute of Occupational Safety and Health, Japan, Kawasaki, Japan.
authors: Masaya
authors: M
authors: Takahashi
authors: Uchisaiwaicho Medical Center, Mizuho Health Insurance Society, Tokyo, Japan.
authors: Takafumi
authors: T
authors: Totsuzaki
mesh_terms: D000328:Adult; D003863:Depression / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013315:Stress, Psychological / Q000453:epidemiology* / Q000503:physiopathology; D000066477:Work Performance