Purpose: Chronic insomnia is highly prevalent in cancer patients. Cognitive-behavioral therapy (CBT) is considered the treatment of choice for chronic primary insomnia. However, no randomized controlled study has been conducted on its efficacy for insomnia secondary to cancer. Using a randomized controlled design, this study conducted among breast cancer survivors evaluated the effect of CBT on sleep, assessed both subjectively and objectively, and on hypnotic medication use, psychological distress, and quality of life.
Patients and methods: Fifty-seven women with insomnia caused or aggravated by breast cancer were randomly assigned to CBT (n = 27) or a waiting-list control condition (n = 30). The treatment consisted of eight weekly sessions administered in a group and combined the use of stimulus control, sleep restriction, cognitive therapy, sleep hygiene, and fatigue management. Follow-up evaluations were carried out 3, 6, and 12 months after the treatment.
Results: Participants who received the insomnia treatment had significantly better subjective sleep indices (daily sleep diary, Insomnia Severity Index), a lower frequency of medicated nights, lower levels of depression and anxiety, and greater global quality of life at post-treatment compared with participants of the control group after their waiting period. Results were more equivocal on polysomnographic indices. Therapeutic effects were well maintained up to 12 months after the intervention and generally were clinically significant.
Conclusion: This study supports the efficacy of CBT for insomnia secondary to breast cancer.