The Impact of Treating Insomnia upon Functional Health, Psychological Wellbeing and Sleep-Related Quality of Life: A Randomised Controlled Trial with Mediation Analysis

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Conference Proceeding

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J Sleep Res


Objectives/Instruction: Digital Cognitive Behavioural Therapy (dCBT) is a scalable and effective intervention for treating the ubiquitous problem of insomnia. However, the majority of people with insomnia seek help because of the daytime consequences of insomnia, and not the night-time effects per se. We investigated the impact of dCBT for insomnia upon functional health, psychological well-being and sleep-related quality of life (QoL), and whether a reduction in insomnia was a mediating factor. Methods: This online, two-arm parallel group randomised trial with waitlist control included 1711 adults with complaints of insomnia (ISRCTN 60530898). Participants were randomized to dCBT (Sleepio ™) or sleep hygiene education (SHE). Online assessments took place at 0 (baseline), 4 (mid-treatment), 8 (post-treatment), and 24 (follow-up) weeks. At week 25 participants allocated to SHE were offered dCBT. Primary outcomes were functional health (Patient Reported Outcome Measurement Information System: Global Health scale), psychological well-being (Warwick-Edinburgh Mental Wellbeing Scale) and sleep-related QoL (Glasgow Sleep Impact Index). Secondary outcomes comprised mood, fatigue, sleepiness, cognitive failures, work productivity and relationship satisfaction. Insomnia was assessed with the Sleep Condition Indicator. All analyses were intention-to-treat. Results: In the dCBT group 681 participants (81%) logged on for at least one dCBT session and 491 participants (57.6%) completed at least 4 sessions. At weeks 4, 8 and 24, dCBT was associated with a small improvement in functional health (Cohen's d: 0.16, 0.31, 0.31 respectively) and psychological well-being (Cohen's d: 0.13, 0.35, 0.38), and a large improvement in sleep-related QoL (Cohen's d: -0.69, -1.38, -1.46) compared with SHE (all p < 0.01). Improvement in insomnia mediated these outcomes (range percent mediated 45.5-84.0%). Symptoms of depression, anxiety, sleepiness, fatigue, cognitive failures and work productivity all demonstrated significant differences in favour of dCBT. Conclusions: dCBT is effective in improving insomnia, functional health, psychological well-being and sleep-related QoL in people screening positive for insomnia disorder. Targeting insomnia complaints could therefore be a therapeutic pathway for addressing selfreported health, well-being and quality of life. In addition, these results confirm that dCBT improves both daytime and night-time aspects of insomnia strengthening existing recommendations of CBT as the treatment-of-choice for insomnia.



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