Highlights
– A 2025 Cochrane review of 21 randomized controlled trials (n=2431) evaluated CBT‑I for insomnia in people with cancer; most participants were female and many were breast cancer survivors (Cai et al., 2025).
– CBT‑I produced small to modest improvements in patient‑reported insomnia severity (Insomnia Severity Index, ISI) and sleep quality (Pittsburgh Sleep Quality Index, PSQI) versus inactive control and vs aerobic activities; certainty of evidence ranged from very low to moderate.
– Subjective diary measures (sleep onset latency, wake after sleep onset, sleep efficiency) showed improvements of varying magnitude; objective sleep measures (actigraphy or polysomnography) largely showed little or no consistent change.
– Safety signals were not evident but adverse event data were sparse and certainty was very low.
Background
Insomnia and disturbed sleep are common and distressing among people with cancer, affecting quality of life, daytime function, mood, and potentially treatment tolerance and recovery. Cognitive behavioural therapy for insomnia (CBT‑I) is the guideline‑recommended first‑line treatment for chronic insomnia in the general population and comprises components such as sleep restriction, stimulus control, cognitive restructuring, sleep hygiene education, and relaxation techniques. However, people with cancer commonly have multimorbidity, treatment‑related symptoms, and psychosocial stressors that may modify response to CBT‑I. As randomized controlled trials (RCTs) of CBT‑I in oncology have proliferated, an up‑to‑date synthesis is required to inform clinicians and health systems about likely benefits, limitations, and research priorities.
Study design
This summary is based on the Cochrane systematic review by Cai et al. (2025), which included randomized controlled trials comparing CBT‑I with any other treatment in adults diagnosed with both cancer and insomnia. The review searched major databases and trial registries through April 2025 without language or date restrictions and excluded quasi‑randomized and cross‑over designs.
Population: 21 RCTs, 2431 randomized participants, predominantly adult females; breast cancer was the most frequently studied diagnosis. Most participants were cancer survivors either undergoing or following cancer treatment.
Interventions: CBT‑I delivered in diverse formats — therapist‑led group or individual sessions, and digital CBT‑I programs — typically four to 12 weeks in duration.
Comparators: The review grouped trials into several comparisons; the two primary contrasts were CBT‑I versus inactive control (wait‑list, usual care, attention‑control) and CBT‑I versus aerobic activity/exercise.
Outcomes: Primary outcomes were patient‑reported insomnia severity (Insomnia Severity Index, ISI), sleep quality (Pittsburgh Sleep Quality Index, PSQI), and serious adverse events (SAEs). Important secondary outcomes included sleep diary variables (sleep onset latency, wake after sleep onset, total sleep time, sleep efficiency) and objective sleep measures (actigraphy or polysomnography). Risk of bias was assessed with RoB 2 and evidence certainty with GRADE.
Key findings
Summary of included evidence
The review included 21 RCTs (2431 participants). Most trials enrolled predominantly female cancer survivors, with breast cancer the most common diagnosis. Delivery of CBT‑I varied (in‑person vs digital; individual vs group), and comparator arms ranged from inactive controls to active interventions such as aerobic exercise. Risk of bias across trials was frequently high; many studies had limitations in allocation concealment, blinding of outcome assessment, and incomplete outcome reporting. Follow‑up was commonly short — outcomes reported at end of treatment.
CBT‑I versus inactive control (primary comparison)
Insomnia severity (ISI): Across 14 studies (n≈1371), CBT‑I reduced ISI scores compared with inactive control (mean difference [MD] −5.86 points; 95% CI −7.22 to −4.51). The Cochrane authors rated this as very low‑certainty evidence. The magnitude represents a small to moderate change on the ISI scale (0–28), and the clinical meaningfulness is uncertain because thresholds for minimally important difference (MID) vary across studies and populations.
Sleep quality (PSQI): From 3 studies (n≈473), CBT‑I improved PSQI scores (MD −3.60; 95% CI −4.95 to −2.24; low‑certainty evidence). This suggests an improvement in self‑reported sleep quality, though evidence quantity was limited.
Serious adverse events (SAEs): Pooled data from 4 trials (n≈765) showed no clear difference in SAEs (risk ratio 1.05; 95% CI 0.07 to 16.77; very low‑certainty), but event counts were low and reporting inconsistent.
Sleep diary outcomes: CBT‑I probably reduced sleep onset latency (SOL) (MD −13.35 minutes; 95% CI −17.18 to −9.51; 9 studies; moderate‑certainty evidence). Wake after sleep onset (WASO) may have been reduced (MD −15.39 minutes; 95% CI −25.23 to −5.56; very low‑certainty). Sleep efficiency (SE) showed small improvements (MD +7.84%; 95% CI 3.62 to 12.06; very low‑certainty). Total sleep time (TST) appeared unchanged (MD +6.43 minutes; 95% CI −8.30 to 21.16; very low‑certainty).
Objective sleep measures: Across a smaller set of trials using actigraphy or polysomnography, CBT‑I resulted in little to no consistent change in objective SOL, WASO, TST, or SE. Point estimates were small and confidence intervals crossed clinically important thresholds in some cases.
CBT‑I versus aerobic activity
Insomnia severity (ISI): In 2 trials (n≈406), CBT‑I provided greater reduction in ISI than aerobic activity (MD −3.53; 95% CI −4.43 to −2.62; low‑certainty evidence).
Sleep quality (PSQI): Across 3 studies (n≈496), CBT‑I modestly improved PSQI versus aerobic activity (MD −1.67; 95% CI −2.63 to −0.72; low‑certainty evidence).
Sleep diary and objective outcomes: Differences were generally small and inconsistent. For some diary measures, there were non‑statistically significant trends favoring CBT‑I; for objective TST, CBT‑I was associated with slightly reduced total sleep time in pooled analyses (MD −13.02 minutes; 95% CI −25.00 to −1.04; low‑certainty evidence), a finding that may reflect sleep restriction elements of CBT‑I in the short term.
Certainty, heterogeneity, and clinical significance
Certainty of evidence ranged from very low to moderate. Limitations included frequent risk of bias, heterogeneity across trial populations and delivery formats, short follow‑up duration, and under‑representation of men and cancer types other than breast. Although many estimates reached statistical significance, clinical significance is less certain — observed ISI reductions versus inactive control (~5.9 points) are of modest magnitude and may not reach all definitions of a minimally important difference in all settings.
Safety
Reporting of adverse events was sparse. Pooled data did not suggest increased SAEs with CBT‑I, but evidence certainty was very low. CBT‑I is physiologically low risk; however, transient daytime sleepiness related to sleep restriction or behavioral changes can occur and should be monitored, particularly in medically vulnerable patients.
Expert commentary
Clinical context: CBT‑I remains the recommended first‑line nonpharmacologic therapy for chronic insomnia in general adult populations (American College of Physicians guideline, 2016). The Cochrane review extends this knowledge to people with cancer and suggests that CBT‑I is likely to produce subjective improvements in sleep for many cancer survivors. However, the modest effect sizes, mixed objective outcomes, and low certainty for many comparisons underscore the need to individualize treatment decisions in oncology care.
Interpretation for practice: For patients with cancer and bothersome insomnia, offering CBT‑I is reasonable where resources and trained providers are available. Digital CBT‑I can expand access and has been used effectively in some trials. Clinicians should set realistic expectations: patients may experience meaningful improvements in perceived sleep onset and sleep quality, but objective sleep duration may not change substantially, particularly in the short term. Integration with management of pain, fatigue, mood disorders, and treatment‑related symptoms is essential.
Research gaps: Future RCTs should prioritize diverse cancer populations (more men, wider cancer types and stages), longer follow‑up to capture durability and functional outcomes, rigorous blinding of outcome assessment where feasible, standardized reporting of harms, and head‑to‑head comparisons of delivery modes (therapist‑led vs digital). Trials should also include measures important to patients (daytime function, mood, treatment adherence) and economic evaluations to inform implementation.
Conclusion
The 2025 Cochrane review provides cautiously encouraging evidence that CBT‑I can improve self‑reported insomnia severity and sleep quality in people with cancer, with probable reductions in subjective sleep onset latency. However, the evidence base is limited by risk of bias, heterogeneity, and short follow‑up, and objective sleep measures show little consistent change. In practice, offering CBT‑I to cancer survivors with insomnia is reasonable when available, but clinicians should counsel patients about likely benefits, uncertainties, and practical constraints. High‑quality, larger, and longer trials are needed to clarify long‑term effectiveness, generalizability across cancer populations, and optimal delivery strategies.
Funding and clinicaltrials.gov
The Cochrane review (Cai et al., 2025) synthesizes trials registered across multiple registries; funding sources varied by included trial. Readers should consult the original Cochrane publication for trial‑level funding and registration details. Ongoing and planned trials of CBT‑I in oncology populations can be identified through clinicaltrials.gov and regional trial registries.
References
1. Cai Z, Tang Y, Liu C, Li H, Zhao G, Zhao Z, Zhang B. Cognitive behavioural therapy for insomnia in people with cancer. Cochrane Database Syst Rev. 2025 Oct 31;10(10):CD015176. doi:10.1002/14651858.CD015176.pub2. PMID: 41170811; PMCID: PMC12576927.
2. Qaseem A, Kansagara D, Forciea MA, Cooke M, Denberg TD; Clinical Guidelines Committee of the American College of Physicians. Management of Chronic Insomnia Disorder in Adults: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2016;165(2):125‑133. doi:10.7326/M15-2175.
Note: Additional trial‑level primary studies and guideline statements are available and were appraised within the Cochrane review. For trial registration numbers and specific funding statements, consult the Cochrane review supplemental materials and clinicaltrials.gov.
