Changes in sleep effort mediate insomnia severity in older adults following online cognitive behavioural therapy.

Abstract

To examine treatment mechanisms of digitally delivered cognitive behavioural therapy for insomnia (CBT-I), this study assessed the mediating effects of dysfunctional beliefs, hyperarousal, locus of control, self-efficacy, sleep effort, and safety behaviours on self-reported insomnia severity in older adults before and following the completion of a self-guided, online CBT-I program. The baseline and follow-up measurements were completed by 62 older adults (55 female, 89%). This was a two-condition within-participant design. Mediation analysis using a parallel mediation model was conducted using the MEMORE macro for repeated measure designs. Out of all the included mediator variables, only a reduction in sleep effort scores (0.88; SE 0.51; 95% CI 0.001-2.00) significantly mediated changes in insomnia severity scores following the intervention. Insomnia severity scores significantly reduced following the intervention (Mpre = 9.84, SD = 5.89, Mpost = 6.87, SD = 4.90); t(61) = 5.19, P = <0.001; d = 0.55 95% CI 0.38-0.93. Sleep in older adults improved following digitally delivered CBT-I, and these changes were influenced by a reduction in sleep control efforts exerted by participants. These findings highlight possible treatment pathways of CBT-I. Further investigation of CBT-I as a strategy to prevent sleep problems is warranted. Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN 12619001509156; http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378451.