A behavioral intervention for insomnia, delivered remotely, can improve sleep quality among women undergoing chemotherapy for breast cancer, according to a new clinical trial. Bright light therapy, on the other hand, failed to live up to expectations.

The trial found that patients who received 6 weeks of cognitive-behavioral therapy for insomnia (CBT-I) had a greater improvement in their sleep problems than those who did not receive the therapy.

In contrast, bright light therapy — a strategy that had shown promise in small studies — did not appear helpful when delivered on its own.

It did not even have the hoped-for synergistic effect when given along with CBT-I, said lead researcher Joshua F. Wiley, PhD, of Monash University in Melbourne, Australia.

But while the findings on light therapy were disappointing, the results add weight to CBT-I as a strategy for patients with cancer-related sleep problems.

And they underscore the need for oncologists to ask patients about their sleep, especially during chemotherapy, Wiley told Medscape Medical News.

He and his colleagues reported the findings in JAMA Network Open.

A Prevalent Problem

Insomnia affects anywhere from 30% to 60% of adults with cancer. Among breast cancer survivors, studies have shown that 62% report poor sleep quality, whereas 43% report moderate-to-severe fatigue. Often, these issues arise during active treatment, especially chemotherapy.

Survivorship guidelines already recommend screening all patients with cancer for sleep difficulties, and CBT-I is considered the first-line therapy. However, most studies have investigated the approach after, rather than during, cancer treatment.

For their trial, Wiley and his colleagues recruited women from five Australian hospitals who were receiving chemotherapy for early-stage or metastatic breast cancer. They randomly assigned 219 patients (mean age, 50.7 years) to receive either CBT-I, bright light therapy, CBT-I plus bright light therapy, or sleep hygiene education only; the other three groups also received the same sleep hygiene education.

Each intervention lasted 6 weeks, with sessions delivered via telephone or video conference and intervention materials sent by email once or twice a week.

In general, CBT-I helps people change their sleep habits and their thinking patterns that contribute to insomnia. In this trial, Wiley said, patients who had trouble falling asleep every night, for example, were advised to go to bed later so they would likely be more fatigued and less likely to toss and turn for hours.

With bright light therapy, the aim is to better align or enhance circadian rhythms by boosting light exposure in the morning and decreasing it in the evening. Trial patients in the light therapy groups were given light glasses to wear for 20 minutes each day at their usual wake-up time.

Better Sleep With CBT-I

During the intervention, all four groups showed a reduction in insomnia symptoms. However, the improvement was greater among women in the two CBT-I groups than among those in the groups that did not receive the therapy: an extra 2-point decline on the 7-item Insomnia Severity Index (P = .002).

Bright light therapy, on the other hand, had no significant impact on insomnia symptoms (-0.88 points; P = .26).

How might the 2-point difference with CBT-I play out for patients in real life? As an example, Wiley said that a patient who initially said she had severe difficulty falling asleep — rating it as a 4 — might have reported it as moderately difficult (a 2 rating) after the intervention.

Wiley’s team also assessed patients’ fatigue ratings. Again, all four study groups showed improvements, but there was no clear advantage with CBT-I.

A sleep medicine specialist who was not involved in the study called the findings on CBT-I “powerful.”

“The main reason why CBT-I works so well is because it addresses sleep-related expectations and sleep-related behaviors,” said Daniel L. Hall, PhD, co-director of behavioral sleep medicine at Massachusetts General Hospital in Boston.

The benefits of CBT-I can also be lasting, Hall told Medscape Medical News. Once people are educated about sleep, they can continue to put the information to work.

Like Wiley, Hall found the lack of additional benefit from bright light therapy surprising. In their report, the researchers noted that because the trial lacked a passive control group, it’s possible that all of the interventions were effective. To answer that question, they added, future studies should include such a control.

For now, Wiley said clinicians can refer patients with cancer-related sleep issues to a specialist who provides CBT-I. Cancer centers often have these specialists on staff, he noted. The International Directory of CBT-I Providers is another resource.

Neither Wiley nor Hall had any relevant disclosures.