Purpose: Research on the association between family-to-work and work-to-family conflicts and sleep problems is sparse and mostly cross-sectional. We examined these associations prospectively in three occupational cohorts.
Methods: Data were derived from the Finnish Helsinki Health Study (n = 3,881), the British Whitehall II Study (n = 3,998), and the Japanese Civil Servants Study (n = 1,834). Sleep problems were assessed using the Jenkins sleep questionnaire in the Finnish and British cohorts and the Pittsburgh Sleep Quality Index in the Japanese cohort. Family-to-work and work-to-family conflicts measured whether family life interfered with work or vice versa. Age, baseline sleep problems, job strain, and self-rated health were adjusted for in logistic regression analyses.
Results: Adjusted for age and baseline sleep, strong family-to-work conflicts were associated with subsequent sleep problems among Finnish women (OR, 1.33 (95 % CI, 1.02-1.73)) and Japanese employees of both sexes (OR, 7.61 (95 % CI, 1.01-57.2) for women; OR, 1.97 (95 % CI, 1.06-3.66) for men). Strong work-to-family conflicts were associated with subsequent sleep problems in British, Finnish, and Japanese women (OR, 2.36 (95 % CI, 1.42-3.93), 1.62 (95 % CI, 1.20-2.18), and 5.35 (95 % CI, 1.00-28.55), respectively) adjusted for age and baseline sleep problems. In men, this association was seen only in the British cohort (OR, 2.02 (95 % CI, 1.42-2.88)). Adjustments for job strain and self-rated health produced no significant attenuation of these associations.
Conclusion: Family-to-work and work-to-family conflicts predicted subsequent sleep problems among the majority of employees in three occupational cohorts.