Pre-sleep arousal, unhelpful beliefs and maladaptive sleep behaviors as mediators in cognitive behavior therapy for insomnia

Abstract

Introduction The purpose with the investigation was to examine whether improvements in pre-sleep arousal, unhelpful beliefs about sleep, and maladaptive sleep behaviors mediate the outcomes in in-person CBT-I. Materials and methods Thirty participants with chronic insomnia previously involved in a randomized controlled trial testing cognitive behavioral therapy versus a waitlist participated. At pretreatment and post-treatment, participants completed questionnaires and sleep diaries assessing pre-sleep arousal, unhelpful beliefs about sleep, maladaptive sleep behaviors, insomnia severity, dysfunction, anxiety, depression, and subjective sleep parameters. Outcome measures were re-administered at a 3-month follow-up. Results The results indicated that decreases in pre-sleep cognitive arousal mediated the effect on dysfunction, and that decreases in pre-sleep somatic arousal had a mediating effect on sleep quality. Reductions in unhelpful beliefs mediated the treatment effect on insomnia severity, dysfunction, and depression. Decreases in bedtime variability mediated the outcome on insomnia severity, and reductions in time in bed had a mediating effect on total wake time and sleep quality. Noteworthy is also that improvements in the outcomes could be attributed to reductions in the mediators (50–70% of the variance). Neither rise time variability nor napping mediated the improvements. Conclusion These findings are clearly supportive of cognitive-behavioral models of insomnia by highlighting pre-sleep arousal, unhelpful beliefs about sleep, and maladaptive sleep behaviors as mediators in the treatment of insomnia. The results are also important for clinical work and for testing new approaches in future research. Acknowledgements We would like to express our appreciation to Sparbankstiftelsen Nya for funding and to the two audiology clinics in Orebro and Karlstad for recruitment.