Predictors of cognitive-behavioral therapy for insomnia (CBT-I) outcomes in individuals with psychiatric disorders: A retrospective observational cohort study

Psychiatry Res. 2026 Jun:360:117058. doi: 10.1016/j.psychres.2026.117058. Epub 2026 Feb 28.

Abstract

Objective: Insomnia disorder is highly prevalent in patients with psychiatric disorders, and cognitive-behavioral therapy for insomnia (CBT-I) remains the first-line treatment. However, remission is achieved in only 40 %, particularly among those with comorbid mood disorders. Identifying factors moderating CBT-I effectiveness is crucial to developing more personalized approaches that optimize outcomes.

Method: 56 patients with insomnia disorder comorbid with psychiatric disorders from a referent sleep psychiatric center participated in a four sessions CBT-I group therapy and completed a series of questionnaires.

Results: The most notable effects were observed at 3-months follow-up, suggesting that the full benefits emerge over time. The intervention led to significant improvements in insomnia severity, with a mean ISI score reduction of 3.9 and a large effect size of r = 0811 (ΔISI: μbaseline = 17.0 to μfollow-up =13.1; W = 421, p<,001) with notable remission rates (18,75 %) and improvements of sleep quality (PSQI) and hyperarousal symptoms (HAS). Several baseline factors predicted treatment outcomes, including hyperarousal and anxiety symptoms, PTSD-related intrusion symptoms, temporal perspective, and emotional regulation. The therapeutic alliance emerged as the strongest predictor of remission, explaining as much as 35,5 % of the variance. Its objective dimension on its own explained 38,4 %, likely due to its more direct relevance to the underlying mechanisms. The effect of CBT-I on hyperarousal symptoms and subjective sleep quality accounted for 41,9 % of the difference in insomnia symptoms, while the most comprehensive model (initial anxiety and CBT-I effects on hyperarousal and sleep quality) explained 48,1 %.

Conclusions: The findings underscore the substantial significance of a strong therapeutic alliance, individual characteristics, and the role of hyperarousal in insomnia, supporting a personalized and relationally grounded approach to insomnia treatment.

Keywords: CBT-I; Hyperarousal; Insomnia disorder; Psychiatric disorders; Therapeutic alliance.

Publication types

  • Observational Study
  • Review

MeSH terms

  • Adult
  • Cognitive Behavioral Therapy* / methods
  • Comorbidity
  • Female
  • Humans
  • Male
  • Mental Disorders* / complications
  • Mental Disorders* / epidemiology
  • Mental Disorders* / therapy
  • Middle Aged
  • Outcome Assessment, Health Care*
  • Psychotherapy, Group
  • Retrospective Studies
  • Sleep Initiation and Maintenance Disorders* / complications
  • Sleep Initiation and Maintenance Disorders* / epidemiology
  • Sleep Initiation and Maintenance Disorders* / therapy
  • Sleep Quality
  • Treatment Outcome