Is improving sleep and circadian problems in adolescence a pathway to improved health? A mediation analysis

Objective: The present study tested whether improvements in sleep and circadian problems mediate the effect of a novel transdiagnostic sleep and circadian intervention (TranS-C) on improvements in 5 health domains (emotional, cognitive, behavioral, social, and physical) in community-residing, evening chronotype adolescents who were at risk for problems in these 5 health domains. Method: Participants were 176 adolescents (age mean [SD] = 14.77 [1.84] years; 58% female) who were randomized to receive 6 sessions of TranS-C or psychoeducation. Putative mediators tested were eveningness, weekday-weekend discrepancy in total sleep time and waketime, daytime sleepiness, Pittsburgh Sleep Quality Index score, and parent-reported sleep-wake problems. Risk in 5 health domains was measured using adolescent self-reported questionnaires, parent-reported Child Behavior Checklist, and ecological momentary assessment (EMA) of problems in the 5 health domains. Results: Reduced eveningness mediated the effects of TranS-C on reducing both self-reported and parent-reported risk in the 5 health domains. Reduction in daytime sleepiness mediated the effects of TranS-C on parent-reported risk in the 5 health domains. Reduction in parent-reported sleep-wake problems mediated the effects of TranS-C on self-reported, parent-reported, and EMA-assessed risk in the 5 health domains. Results did not support the other hypothesized mediators. Conclusions: TranS-C exerts effects on reducing risk in multiple mental and physical health domains through reducing sleep and circadian problems in evening chronotype adolescents. Further research of TranS-C in other samples to assess its benefits for sleep and circadian problems as well as mental and physical health is warranted.