Review of 19 trials links CBT for insomnia to lower suicidal ideation after treatment
A systematic review and meta-analysis in Nature Mental Health pooled 19 randomised controlled trials with 4,974 adults with insomnia. Cognitive behavioural therapy for insomnia (CBT-I) was associated with a 23% reduction in suicidal ideation severity after treatment compared with control conditions, with high-certainty evidence; the difference at later follow-ups was unclear.
What happened
The review, by Cagdas Türkmen and colleagues, examined the effect of CBT-I on suicidal ideation severity, suicidal behaviours and suicide deaths in adults with insomnia. CBT-I is the recommended first-line treatment for insomnia.
After treatment, suicidal ideation severity was 23% lower with CBT-I than with control conditions (ratio of means 0.77; 95% confidence interval 0.66 to 0.90), and the authors rated this evidence high certainty. This is a relative difference in symptom scores, not a 23-point fall in the share of people with suicidal thoughts. At follow-up the difference was unclear, with evidence rated very low to moderate certainty.
Across nine trials that reported them, two participants who received CBT-I reported suicide attempts, against none in control groups. No suicide deaths occurred. People with a recent suicide attempt or at high suicide risk were generally excluded from the trials.
Why it matters
Insomnia is a common and modifiable risk factor for suicidal thoughts. The authors conclude that CBT-I modestly reduces suicidal ideation severity and could be an adjunct to suicide prevention, including in scalable digital and brief formats.
The evidence does not show that CBT-I prevents suicide attempts or deaths, or that its effect lasts, and it says little about people at high risk. It is not a substitute for suicide risk assessment or crisis care.
What happens next
Open questions include longer-term effects, outcomes in people at elevated risk, effects on suicidal behaviour, and how well self-guided digital CBT-I engages groups such as people with severe mental illness.