An interventional study of Re-Timer® light therapy glasses and Usual Care in Gynecologic Cancer Survivors, Sleep Quality and Fatigue, sponsored by Chang Gung Memorial Hospital. Completed at 1 site in Taiwan. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-08-20.
Sponsored by Chang Gung Memorial Hospital · Not applicable, Interventional, and Treatment
Objective: This study aimed to examine the efficacy of light therapy in improving sleep quality, reducing fatigue, and alleviating emotional symptoms among patients diagnosed with gynecologic cancer.
Methods: A randomized controlled trial was conducted at a medical center in northern Taiwan. Inclusion criteria included patients aged 18 years or older with a physician-confirmed diagnosis of gynecologic cancer and a score of ≥ 9 on the Chinese version of the Insomnia Severity Index (ISI-C). Eligible participants were randomly assigned to an experimental group or a control group (each with 47 subjects). At baseline (T0), all participants completed a demographic and treatment questionnaire, the ISI-C, the Taiwan version of the Brief Fatigue Inventory (BFI-T), and the Distress Thermometer (DT). The experimental group then underwent daily light therapy sessions via a circadian regulator for 30-40 minutes within 30 minutes of waking for four weeks. Meanwhile, the control group continued their usual routines during the same period. Follow-up assessments were conducted on days 7 (T1), 14 (T2), 21 (T3), and 28 (T4) post-intervention. Data was analyzed using SPSS 26.0, and generalized estimating equations (GEE) were employed to assess the effectiveness of light therapy.
Results: Generalized Estimating Equations (GEE) will be applied to examine group differences over time in sleep quality, fatigue, and emotional symptoms, in order to assess the effects of the intervention.
Conclusion: Light therapy is proposed as a potentially safe, low-risk, and cost-effective non-pharmacological intervention for improving sleep quality, reducing fatigue, and alleviating emotional distress in patients with gynecologic cancer following chemotherapy. This study is designed to evaluate the feasibility and potential effects of light therapy in this population, with the goal of informing future clinical applications.
Background and Rationale
Survivors of gynecologic cancers often experience persistent sleep disturbances, cancer-related fatigue, and emotional distress even after treatment has ended. These symptoms can significantly affect daily functioning, emotional well-being, and overall quality of life. Bright light therapy (BLT), a non-pharmacological intervention, has been shown in other populations to help regulate circadian rhythms and improve sleep and fatigue by suppressing melatonin levels. However, the application of BLT in gynecologic cancer survivors has not been well studied. This trial is designed to explore the potential of BLT in addressing these symptoms in this specific population.
Objectives
The primary objective is to evaluate the effects of a four-week bright light therapy intervention on sleep quality, fatigue, and emotional symptoms among gynecologic cancer survivors. It is hypothesized that participants receiving BLT will demonstrate improved outcomes in these domains compared to those receiving usual care.
Study Design
This is a randomized, controlled, single-blind trial with a parallel-group design. Eligible participants will be randomly assigned in a 1:1 ratio to either the intervention group (BLT) or the control group. Outcome assessors will remain blinded to group allocation throughout the study.
Intervention
Participants in the intervention group will receive bright light therapy using Re-Timer® light therapy glasses, which emit green-blue light at an intensity of 506 lux. Participants will be instructed to wear the glasses for 45 minutes each morning over four consecutive weeks. Sessions are self-administered at home between 7:00 AM and 9:00 AM, based on circadian rhythm guidance.
Control Condition
The control group will receive usual care and will not be provided with any light therapy. Participants in this group will be instructed to maintain their typical daily routines and avoid introducing new interventions that could impact sleep or mood during the study period.
Outcome Measures and Timepoints
Outcome data will be collected through an online questionnaire via the LINE messaging app at the following timepoints:
T1: Day 7 of intervention
T2: Day 14 of intervention
T3: Day 21 of intervention
T4: Day 28 of intervention
The following instruments will be used:
Insomnia Severity Index - Chinese version (ISI-C): to assess insomnia symptoms
Brief Fatigue Inventory - Taiwanese version (BFI-T): to assess cancer-related fatigue
Distress Thermometer (DT): to assess emotional distress
1,856 studies on the registry are indexed under Sleep Initiation and Maintenance Disorders; 594 are open to participants now.
This study's enrollment of 94 is above the median of 73 across 1,631 interventional studies indexed under Sleep Initiation and Maintenance Disorders.
Browse Sleep Initiation and Maintenance Disorders studies →Chang Gung Memorial Hospital is the lead sponsor of 1,064 studies on the registry; 235 are open to participants now.
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Exclusion Criteria:
Participants in this group received daily morning exposure to bright white light (506 lux) using the Re-Timer® light therapy glasses for 45 minutes per day, over a 4-week period.
Device: Re-Timer® light therapy glasses
Participants in this group received usual care and did not receive any light therapy intervention during the study period.
Other: Usual Care
Participants wore Re-Timer® glasses that emitted bright white light at 506 lux for 30 minutes each morning, over a 4-week intervention period.
Participants received standard follow-up care with no light therapy intervention during the 4-week period.
Change in Insomnia Severity Index - Chinese version (ISI-C)
To evaluate the change in insomnia severity before and after the intervention using the Insomnia Severity Index - Chinese version (ISI-C). Higher scores indicate more severe insomnia.
Time frame: Day 7 (T1), Day 14 (T2), Day 21 (T3), and Day 28 (T4) after intervention start.
Cancer-related fatigue (BFI-T)
To assess the level of cancer-related fatigue using the Brief Fatigue Inventory - Traditional Chinese version (BFI-T). The BFI-T includes 9 items rated on a 0-10 numeric scale, with higher scores indicating greater fatigue severity and interference.
Time frame: Day 7 (T1), Day 14 (T2), Day 21 (T3), and Day 28 (T4) after the start of the intervention.
Emotional distress (Distress Thermometer, DT)
To measure overall emotional distress using the Distress Thermometer (DT), a single-item visual analog scale ranging from 0 (no distress) to 10 (extreme distress). Participants indicate their distress levels during the past week.
Time frame: Day 7 (T1), Day 14 (T2), Day 21 (T3), and Day 28 (T4) after the start of the intervention.
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Plan to share: Yes — De-identified individual participant data (IPD) that underlie the results reported in this article will be shared. The shared data will include the variables analyzed for primary and secondary outcomes, baseline characteristics, and adverse events (if applicable). Data will be available upon reasonable request to qualified researchers for the purpose of academic and non-commercial use. Interested researchers must provide a methodologically sound proposal and obtain approval from the principal investigator and the Institutional Review Board (IRB) of the host institution. Data will be available starting 6 months after publication of the study results and will remain available for up to 3 years. Requests for data sharing should be submitted to the corresponding author via email.
Supporting information: Study protocol
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