title: Insomnia symptoms, sleep duration, and disability pensions: a prospective study of Swedish workers.
abstract: BACKGROUND
  Previous studies have found insomnia and long sleep duration to be independently associated with subsequent disability pension (DP). However, the issue of a possible gender-based pattern in this context has received little attention.
  
  
  OBJECTIVE
  This study aims to assess the impact of insomnia symptoms and sleep duration on the DP rates among Swedish women and men during a 12-year follow-up period.
  
  
  METHODS
  The participants, from the general population of Malmö, Sweden, were enrolled from 1992 to 1994 (n = 4,319; participation rate 41 %), aged 45-64, healthy, and employed ≥30 h per week. Baseline inquiry data concerning psychosocial circumstances and self-reported sleep habits were compared with official register-based DP rates.
  
  
  RESULTS
  Five hundred and nine persons were granted a DP. Insomnia symptoms, affirmed by 33 % of the men and 41 % of the women, were associated with receiving a DP; the hazard ratios in the fully adjusted model were 1.4 for both men [95 % confidence interval (CI) 1.1, 1.9] and women (95 % CI 1.1, 1.7). The fully adjusted hazard ratio for women sleeping ≥9 h was 7.8 (95 % CI 3.7, 16.6) for DP due to a mental disorder. In the age-adjusted analyses, the sub-domain "difficulties falling asleep" was related to DP due to mental disorders in men and DP due to cardiovascular diseases in women.
  
  
  CONCLUSIONS
  The findings suggest that preventing and treating insomnia symptoms could reduce DP and that disease mechanisms linking sleep disturbances to DP may differ by gender.
authors.affiliation: Social Medicine and Global Health, Malmö University Hospital, Lund University, Jan Waldenströms gatan 35, 205 02, Malmö, Sweden, catarina.canivet@med.lu.se.
authors.forename: Catarina
authors.initials: C
authors.lastname: Canivet
authors.forename: Carin
authors.initials: C
authors.lastname: Staland-Nyman
authors.forename: Sara I
authors.initials: SI
authors.lastname: Lindeberg
authors.forename: Robert
authors.initials: R
authors.lastname: Karasek
authors.forename: Mahnaz
authors.initials: M
authors.lastname: Moghaddassi
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Östergren
mesh_terms: D002318:Cardiovascular Diseases / Q000523:psychology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D001523:Mental Disorders / Q000523:psychology; D008875:Middle Aged; D010415:Pensions / Q000706:statistics & numerical data*; D011446:Prospective Studies; D012737:Sex Factors; D012890:Sleep / Q000502:physiology*; D007319:Sleep Initiation and Maintenance Disorders / Q000453:epidemiology / Q000503:physiopathology* / Q000517:prevention & control; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors