Guided internet-based treatment for insomnia and depression

Abstract: Background. Insomnia and depression are two of the most prevalent and costly disorders, and comorbidity between the two is common. Treatment of insomnia, other than pharmacological, is often overlooked in spite of the existence of effective psychological treatments. When insomnia is comorbid with depression, treatment of depression is usually prioritized, but not quite sufficient. The insomnia treatment with the strongest evidence is Cognitive Behavioral Therapy for insomnia (CBT-i). Due to a lack of trained CBT-i-therapists, therapist-guided Internet-based CBT-i (ICBT-i) has emerged as an alternative to face-to-face treatments. Aims. To challenge the treatment paradigm for comorbid insomnia and depression by comparing ICBT-i to ICBT-d (Internet-based CBT for depression) (Study I). To strengthen the evidence for ICBT-i by comparing ICBT-i to face-to-face treatment (Study II) and by doing a 3-year follow-up of a previous trial (Study III). To investigate qualitative aspects of Study I (Study IV). Studies. Four studies were done: Study I, a randomized controlled trial (RCT, n=43) comparing ICBT-i to ICBT-d in a sample with comorbid insomnia and depression. Study II, a non-inferiority RCT (n=48) comparing ICBT-i to group-delivered CBT-i in a sample with insomnia and various comorbidities, including mild to moderate depression. Study III, a 3-year follow-up of an RCT (n=148) comparing ICBT-i to an active control treatment. Study IV, a qualitative study investigating facilitating and hindering factors in participants’ work with the treatments in Study I. Results. Study I: ICBT-i turned out to be overall more beneficial than ICBT-d for patients with both insomnia and depression regarding e.g. effects on insomnia severity (effects on depression were similar) and reduction of sleep medication use. Study II: ICBT-i turned out to be highly effective and non-inferior to group-delivered CBT-i regarding insomnia severity, both directly after treatment and after six months. Study III: The 3-year follow-up of ICBT-i showed that the large effect on insomnia severity observed directly after treatment was maintained over time, and led to reduced consumption of sleep medication and other insomnia treatments compared to participants in the active control group. Both studies II and III showed that ICBT-i also reduced depressive symptom severity significantly. Study IV: The qualitative analyses showed that ICBT-i was easier to work with, and more positively regarded than ICBT- d, according to the participants. Multiple comorbidities were more hindering in ICBT-d than in ICBT-i. Conclusions. ICBT-i is effective in reducing insomnia severity, also in patients with comorbid disorders, and that the effects are maintained over time. ICBT-i can lead to reduced sleep medication use and decreased depressive symptoms. The findings for comorbid insomnia and depression indicate that insomnia needs to be prioritized for evidence-based treatment, also when it is comorbid with depression.