title: Possible health-protecting effects of feeling useful to others on symptoms of depression and sleep disturbance in the workplace.
abstract: OBJECTIVE
  The aim of this study was to examine the health-protecting effects of feeling useful to others on symptoms of depression and sleep disturbance in the workplace, as well as its buffering effects on associations between stressful work environments and symptoms of depression and sleep disturbance.
  
  
  METHODS
  The subjects of this cross-sectional survey were 773 Japanese workers (response rate: 64.8%) of five organizations. Feelings of being useful to others were assessed with one simple question used in a previous study. Psychosocial work environment, sleep disturbance, and depressive symptoms were assessed using the Japanese versions of the Effort-Reward Imbalance Questionnaire, the Pittsburgh Sleep Quality Index, and the 28-item General Health Questionnaire, respectively. We tested for linear and interactive effects with hierarchical regression analyses.
  
  
  RESULTS
  Feeling useful to others was significantly (p<0.05) and negatively associated with scores of depression and sleep disturbance both in the univariate analyses and after adjusting for age in both genders. Significant (p<0.05) interactions showed that, in both genders, as the effort-reward balance worsened, symptoms of depression increased, but feeling useful to others buffered the associations.
  
  
  CONCLUSIONS
  The results support the notion that feeling useful to others in both genders in the workplace has possible health-protecting effects.
authors.affiliation: Department of Public Health, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan. jirosinryounaika-tky@umin.ac.jp
authors.forename: Jiro
authors.initials: J
authors.lastname: Takaki
authors.forename: Akizumi
authors.initials: A
authors.lastname: Tsutsumi
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Irimajiri
authors.forename: Asako
authors.initials: A
authors.lastname: Hayama
authors.forename: Yuri
authors.initials: Y
authors.lastname: Hibino
authors.forename: Sakiko
authors.initials: S
authors.lastname: Kanbara
authors.forename: Noriko
authors.initials: N
authors.lastname: Sakano
authors.forename: Keiki
authors.initials: K
authors.lastname: Ogino
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003863:Depression / Q000523:psychology*; D005260:Female; D006304:Health Status; D006801:Humans; D007398:Interpersonal Relations; D007564:Japan; D007588:Job Satisfaction; D008297:Male; D008875:Middle Aged; D012649:Self Concept; D012737:Sex Factors; D012893:Sleep Wake Disorders / Q000523:psychology*; D017132:Workplace