Insomnia Symptoms, Sleep Duration, and Disability Pensions: a Prospective Study of Swedish Workers

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. PURPOSE: 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. METHOD: 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. CONCLUSION: 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