Preventing Sleep Disruption With Bright Light Therapy During Chemotherapy for Breast Cancer: A Phase II Randomized Controlled Trial

Abstract

Purpose: The goal of this study was to examine whether daily increased morning light exposure would maintain or improve sleep and the circadian pattern of relatively more activity in the day and less during the night in women undergoing chemotherapy for breast cancer.

Patients and methods: Participants were 39 women with newly diagnosed breast cancer, randomized to either 30-mins of daily morning bright white light (BWL) or dim red light (DRL). Sleep/wake was measured objectively for 72-h with wrist actigraphy and subjectively with the Pittsburgh Sleep Quality Index (PSQI) prior to and during chemotherapy cycles 1 and 4. The study was registered with the National Institutes of Health ClinicalTrials.gov (Clinical Trials number: NCT00478257).

Results: Results from actigraphy suggested that compared to the DRL group, women in the BWL group had longer night-time sleep, fewer sleep disturbances during the night, and had fewer and shorter daytime naps at the end of cycle 4 of chemotherapy as well as exhibiting less activity at night and more activity during the day by the end of cycle 4. Results from PSQI indicated that components of sleep quality improved but daytime dysfunction deteriorated during cycle 4 treatment in the BWL group; meanwhile the DRL group used more sleep medications in the treatment weeks which might have led to the improved sleep quality during the recovery weeks of both cycles.

Conclusion: These results suggest that bright white light therapy administered every morning on awakening may protect women undergoing chemotherapy for breast cancer from nighttime sleep and daytime wake disruption. Randomized clinical trials in larger samples are needed to confirm these findings.

Keywords: PSQI; actigraphy; activity; breast cancer; light therapy; sleep.

Conflict of interest statement

SA-I was a consultant for Eisai, Biogen, Merck, Idorsia, and Pear Therapeutics. NJ was a student at UCSD at the time of the study and currently works for J&J which has had no influence or funding of this study. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Copyright © 2022 Rissling, Liu, Youngstedt, Trofimenko, Natarajan, Neikrug, Jeste, Parker and Ancoli-Israel.

Figures

FIGURE 1

Consort table depicting sample sizes at each point of the study.

FIGURE 2

Flow diagram depicting study procedures including timing of actigraphy and questionnaire assessments.

FIGURE 3

Bar graphs depicting nighttime (A) total sleep time, (B) sleep percentage, and (C) total wake time for both bright white light (BWL) and dim red light (DRL) treatment groups from baseline through the treatment weeks (TW) and recovery weeks (RW) of chemotherapy cycles 1 and 4. With the exception of recovery week of cycle 1 (C1RW), the BWL group demonstrated longer total sleep time (A) compared to baseline. On the other hand, DRL group demonstrated longer total wake time (C) and lower sleep percentage (B) during the recovery week of cycle 4 (C4RW). *p < 0.05 for group-by-time interaction, indicating that compared to DRL group, BWL group had significant longer total sleep time during cycle 4 (both C4TW and C4RW), significant higher sleep percentage and shorter total wake time during C4RW.

FIGURE 4

Bar graphs depicting daytime (A) number of naps, (B) total nap time, and (C) mean nap duration for both BWL and DRL treatment groups from baseline through the TW and RW of chemotherapy cycles 1 and 4. With the exception of recovery weeks (C1RW and C4RW), the DRL group demonstrated more frequent (A) and longer (B) naps as chemotherapy treatment progressed. Mean nap duration (C) also increased at C1TW for the DRL group, *p < 0.05 for group-by-time interaction, indicating that compared to DRL group, BWL group had significant fewer naps and shorter total nap time during cycle 4 (both C4TW and C4RW).

FIGURE 5

Bar graphs depicting average counts per minute for both (A) the nighttime sleep period and (B) the daytime wake period activity in the BWL and DRL treatment groups from baseline through the TW and RW of chemotherapy cycles 1 and 4. As depicted in panel (A), the average nighttime activity decreased in the BWL group while the DRL increased from baseline to the end of cycle 4 (C4RW). Conversely, as depicted in panel (B), the average daytime activity decreased in the DRL group from baseline to the treatment weeks of cycle 1 (C1TW) and cycle 4 (C4TW). *p < 0.05 for group-by-time interaction, indicating that compared to DRL group, BWL group had significant less daytime activity decrease during C4TW.