Breast cancer survivors sleep better when they have a personalized light therapy schedule
Many breast cancer survivors have fatigue and sleep difficulties long after their cancer has gone into remission.
“My patients were exhausted during the day, but they didn’t sleep well at night,” said associate professor Horng-Shiuann Wu of the College of Nursing.
“I saw that weariness and sleep disturbance were linked; they had a bad impact on cancer patients, but we didn’t have a cure.”
Light therapy was being used by one of Wu’s colleagues to help Alzheimer’s patients in nursing homes reset their circadian rhythm.
The circadian rhythm is a 24-hour cycle that teaches our bodies when to sleep and when to be awake. Wu was curious if light treatment could affect her patients’ sleep and wake cycles as well.
Wu’s findings were published online in the journal Chronobiology International on November 3, 2021.
“We know that cancer disrupts the circadian cycles of patients,” Wu said. “With light therapy, I believe we could restore a patient’s circadian cycle.”
Cancer causes a disruption in the body’s circadian rhythm, which can have a cumulative effect on the patient over time. Even when people are done with treatment and are in remission, they can still be tired and have trouble sleeping for years.
Each patient is given a light therapy visor to wear for 30 minutes a day for two weeks as part of the treatment.
In previous studies, the visor used the highest intensity of light in the blue-green spectrum, which has been shown to be successful in resetting circadian cycles.
Previous research has also shown that the time of day the therapy was administered had a greater impact on the patient’s sleep cycle than the light itself.
Light treatment was suggested for patients who needed to fall asleep earlier in the day within 30 minutes of waking up. Early evening therapy was given to patients who needed to retire later in the day.
Exposure to light at the wrong moment will exacerbate your circadian rhythm disruption, “Wu explained. “I tailored the time for each patient so that I could get the desired impact (e.g., going to bed earlier or later).”
During her research, Wu wants to learn more about how light exposure, wavelength, and circadian cycles work together to help her patients live better lives by reducing or eliminating these symptoms.