Study ObjectivesTo examine cross-sectionally and prospectively whether informal caregiving is related to sleep disturbance among caregivers in paid work.MethodsParticipants (N = 21604) in paid work from the Swedish Longitudinal Occupational Survey of Health. Sleeping problems were measured with a validated scale of sleep disturbance (Karolinska Sleep Questionnaire). Random-effects modeling was used to examine the cross-sectional association between informal caregiving (self-reports: none, up to 5 hours per week, over 5 hours per week) and sleep disturbance. Potential sociodemographic and health confounders were controlled for and interactions between caregiving and gender included. Longitudinal random-effects modeling of the effects of changes in reported informal caregiving upon sleep disturbance and change in sleep disturbance was performed.ResultsIn multivariate analyses controlling for sociodemographics, health factors, and work hours, informal caregiving was associated cross-sectionally with sleep disturbance in a dose–response relationship (compared with no caregiving, up to 5 hours of caregiving: β = 0.03; 95% CI: 0.01, 0.06, and over 5 hours: β = 0.08; 95% CI: 0.02, 0.13), results which varied by gender. Cessation of caregiving was associated with reductions in sleep disturbance (β = −0.08; 95% CI: −0.13, −0.04).ConclusionsThis study provides evidence for a causal association of provision of informal care upon self-reported sleep disturbance. Even low-intensity care provision was related to sleep disturbance among this sample of carers in paid work. The results highlight the importance of addressing sleep disturbance in caregivers.