To Örebro University

Introduction: An increasing number of children and adolescents divide their time between their separated parents' homes. Although marital conflict is disadvantageous for children's sleep, little is known about how children of separated parents sleep. The objective was to investigate the association between children's custody arrangements and sleep habits and sleep initiation difficulties.

Materials and Methods: Cross-sectional questionnaire data from the 2013 Health Behaviours of School-aged Children was used. The sample included over 7000 adolescents (50% girls), aged 11-15. Nuclear families were used as a reference in all analyses. The sleep issues were defined as follows: Less than 7 h of sleep = insufficient sleep; sleep initiation difficulties >1 per week = insomnia; bedtimes after 11 pm = late bedtimes; more than 2h variability between weekend and weekday bedtimes = jetlag. Short sleep duration, insomnia, late bedtimes and jetlag were respectively used as outcomes from regression analyses where custody forms, gender, and family affluence were used as predictors.

Results: The results show differences by custody arrangement, but they are not uniform across the dependent variables. Children and adolescents in sole maternal custody were less likely to sleep as much as recommended (P < .001), more likely to have late bedtimes (P < .001), report sleep initiation difficulties (P < .01) and to report social jetlag between school mornings and weekends (P < .05) compared to those in 2-parent families. Shared physical custody was associated with a higher likelihood of late bedtimes (P < .05) and sleep initiation difficulties (P < .05) compared to those in 2-parent families, but not of sleeping less than recommended or reporting social jetlag. Less-than-equal sharing was generally associated with worse sleep than in 2-parent families.

Conclusions: As custody arrangements seem to be associated with sleep, it is important to understand the mechanisms behind the findings.