Work productivity loss with depression, diagnosed and undiagnosed, among workers in an Internet-based survey conducted in Japan

J Occup Environ Med. 2015 Jan;57(1):105-10. doi: 10.1097/JOM.0000000000000310.


Objective: The aim of this study was to investigate whether depression severity was associated with work impairments, regardless of the diagnosis.

Methods: We conducted a cross-sectional study among 17,820 Japanese workers using an Internet-based survey. Work impairments were assessed using the Work Productivity and Activity Impairment questionnaire. Participants were grouped according to whether they had a past-year diagnosis of depression by physicians and current depression severity assessed with the Patient Health Questionnaire-9.

Results: Among the undiagnosed, high severity respondents had greater overall work impairment than low severity respondents (33.3% vs 14.8%). Significant interactions between diagnosis and severity indicated greater impairments among undiagnosed than among diagnosed respondents (except on absenteeism).

Conclusions: Depression severity was associated with work productivity loss, even among the undiagnosed, suggesting a need for early detection, referral, and treatment of depression in the workplace.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absenteeism*
  • Adult
  • Cross-Sectional Studies
  • Depression / diagnosis*
  • Depression / psychology
  • Efficiency*
  • Female
  • Health Surveys
  • Humans
  • Internet
  • Japan
  • Male
  • Middle Aged
  • Severity of Illness Index*
  • Surveys and Questionnaires