Sleep problems:: a predictor of long-term work disability?: A four-year prospective study

Aims: This study investigates sleep problems as a predictor of long-term work disability. Methods: Data from a community based four-year prospective study were used. In 1990, all inhabitants of the municipality of Ullensaker, Norway, belonging to six age cohorts (20-22, 30-32, 40-42, 50-52, 60-62, and 70-72 years), were mailed a questionnaire. Of the 1-788 responders who were working and not older than 62 years, 1,476 (80%) returned a second questionnaire four years later (1994). Results: Reporting mediocre or poor sleep (in contrast to good) in 1990 was significantly related to long-term work disability (> 8 weeks) during the previous 12 months in 1994 (odds ratio = 2.16; 95% confidence interval = 1.26-3.72), after adjustments for age, gender, civil status, body mass index, emotional symptoms, musculoskeletal pain, self-evaluated health. smoking, physical exercise, job satisfaction, and work characteristics. Conclusion: The study indicates that sleep problems are a predictor of long-term work disability.