title: Sleep problems and sickness absence among middle-aged employees.
abstract: OBJECTIVE
  The aim of this study was to examine whether sleep problems predict subsequent sickness absence         among middle-aged public sector employees.
  
  
  METHODS
  The data included 5391 female and 1454 male employees of the City         of Helsinki from questionnaire surveys at baseline in 2000-2002. These data were prospectively linked to the         employer's sickness absence register data, with a mean follow-up time of 4.1 years. Using Poisson regression         analysis, we examined associations between sleep problems (none, rare, occasional, and frequent), as indicated by the         Jenkins Sleep Questionnaire, and self-certified short (1-3 days) and medically confirmed intermediate (4-14         days) and long (≥15 days) sickness absence spells. Sociodemographic factors, working conditions, work-family         interface, health behaviors, and health status were obtained from the baseline surveys.
  
  
  RESULTS
  At baseline, 21% of         women and 17% of men reported frequent sleep problems. Frequent sleep problems were associated with subsequent sickness         absence spells irrespective of length of absence among both women and men after adjusting for age. After full         adjustment for all covariates, the associations attenuated but remained for self-certified sickness absence [risk ratio         (RR) for women 1.40, 95% confidence interval (95% CI) 1.25-1.56 and RR 1.59, 95% CI 1.24-2.03 for men], and         medically confirmed intermediate (RR 1.34, 95% CI 1.17-1.52 and RR 1.35, 95% CI 1.02-1.77, for women and         men, respectively) and long (RR 1.58, 95% CI 1.29-1.94 and RR 1.44, 95% CI 0.93-2.21, for women and men,         respectively) sickness absence spells. Occasional sleep problems were also associated with sickness absence, but the         associations were somewhat weaker.
  
  
  CONCLUSIONS
  In occupational healthcare, sleep problems should be addressed to         prevent their occurrence and subsequent ill-health and sickness absence.
authors.affiliation: Hjelt Institute, Department of Public Health, University of Helsinki, Helsinki, Finland. ossi.rahkonen@helsinki.fi
authors.forename: Ossi
authors.initials: O
authors.lastname: Rahkonen
authors.forename: Tea
authors.initials: T
authors.lastname: Lallukka
authors.forename: Erkki
authors.initials: E
authors.lastname: Kronholm
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Eero
authors.initials: E
authors.lastname: Lahelma
authors.forename: Mikko
authors.initials: M
authors.lastname: Laaksonen
mesh_terms: D000041:Absenteeism; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018582:Sick Leave / Q000706:statistics & numerical data*; D012893:Sleep Wake Disorders / Q000453:epidemiology*