title: Economic difficulties and subsequent sleep problems: evidence from British and Finnish occupational cohorts.
abstract: BACKGROUND
  Social determinants of sleep may prove to be as important as health status. In this study we examined the extent to which persistent and changing economic difficulties are associated with sleep problems in two prospective occupational cohorts.
  
  
  METHODS
  We used data from Finnish (baseline 2000-2002; follow-up 2007; n=6328) and British (baseline 1997-1999; follow-up 2003-2004; n=5002) public sector employees. Economic difficulties, sleep problems, and a variety of covariates were assessed at baseline and follow-up.
  
  
  RESULTS
  Prevalence of frequent sleep problems at follow-up was 27% and 20% among women and men in the Finnish cohort, and 34% and 27% in the British cohort, respectively. Odds for sleep problems were higher among those with persistent economic difficulties (frequent economic difficulties at baseline and follow-up) compared to those with no difficulties. This association remained after multiple adjustments, including parental and current socioeconomic position, in the Finnish (OR 1.72, 95% CI 1.35-2.18) cohort. Increases in economic difficulties were similarly associated with sleep problems in the Finnish and the British cohort.
  
  
  CONCLUSIONS
  Evidence from two occupational cohorts suggests strong associations between economic difficulty and poor sleep. Awareness of this association will help health care professionals identify and prevent sleep problems.
authors.affiliation: Hjelt Institute, Department of Public Health, University of Helsinki, Finland. tea.lallukka@helsinki.fi
authors.forename: Tea
authors.initials: T
authors.lastname: Lallukka
authors.forename: Jane E
authors.initials: JE
authors.lastname: Ferrie
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Shipley
authors.forename: Ossi
authors.initials: O
authors.lastname: Rahkonen
authors.forename: Eero
authors.initials: E
authors.lastname: Lahelma
mesh_terms: D000328:Adult; D057172:Economic Recession / Q000706:statistics & numerical data*; D004651:Employment / Q000706:statistics & numerical data*; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D012893:Sleep Wake Disorders / Q000191:economics* / Q000453:epidemiology* / Q000523:psychology; D012959:Socioeconomic Factors; D013315:Stress, Psychological / Q000191:economics / Q000453:epidemiology / Q000523:psychology; D006113:United Kingdom / Q000453:epidemiology