Brief cognitive behavioral therapy for insomnia (CBT-I) may be superior to bright light therapy (BLT) for improving symptoms of insomnia in women with breast cancer who are being treated with chemotherapy, a study in JAMA Network Open has found.Why It’s Relevant
Insomnia symptoms such as daytime sleepiness, waking up early, and waking up frequently during the night are common and distressing in women with breast cancer. The addition of chemotherapy can worsen insomnia and fatigue, with up to 70% of women undergoing treatment experiencing such symptoms.
By the Numbers
- Researchers analyzed data from 208 women receiving chemotherapy for early or metastatic breast cancer. All women received sleep hygiene education along with six weeks of CBT-I, BLT, both, or neither.
- CBT-I consisted of behavioral strategies such as stimulus control and bed restriction, cognitive strategies that addressed dysfunctional beliefs about sleep, and cancer-specific strategies such as mindfulness for physical discomfort. BLT involved wearing bright light glasses every morning for 20 minutes.
- Scores on the Insomnia Severity Index (ISI) dropped among all participants at six weeks. However, the decrease was most pronounced in the women who received CBT-I (7.35 points) or CBT-I plus BLT (8.26 points). In comparison, scores dropped 6.04 points in the BLT group and 5.18 points in the group receiving only sleep hygiene education.
- Neither CBT-I nor BLT appeared to have a significant effect on fatigue symptoms.
The Other Side
The study was not blinded, and there was no true control group. The findings cannot be generalized to men or other cancers, though the researchers noted there is no reason to expect that either CBT-I or BLT would have distinct effects in breast cancer.
Takeaway Message
“Taken together, these findings support the possibility that all treatments in our trial were effective,” the researchers wrote, noting that both CBT-I and BLT reduced ISI scores by at least six points, which is considered a clinically relevant cutoff. “However, attributing these effects to our interventions is limited without a no-treatment control; future studies should incorporate such controls.”
Related Information
Source
Trang Thuy Do, et al. Cognitive behavior vs bright light therapy for insomnia in women undergoing chemotherapy for breast cancer: a randomized clinical trial. JAMA Network Open. Published online August 27, 2026. doi:10.1001/jamanetworkopen.2026.30320
(Image: Getty Images/iStock/Andrii Lysenko)
