Patients with migraine experienced an approximately 60% reduction in pain intensity and the number of headache days per month after exposure to green light therapy, according to the results of a small study at the University of Arizona at Tucson.
“This is the first clinical study to evaluate exposure to green light as a potential preventive treatment for patients with migraine,” said lead author Mohab M. Ibrahim, MD, PhD, in a Press release. “Now I have another tool in my toolkit for treating one of the most difficult neurological conditions – migraine.”
“In view of the safety, affordability and effectiveness of exposure to green light, there is interest in conducting a larger study,” he and co-authors from the university wrote in their report. article, which was published in Cephalgia.
The study included 29 adult patients (mean age 52.2 years), 22 with chronic migraine, and the remainder with episodic migraine who were recruited from the University of Arizona / Banner Medical Chronic Pain Clinic. Center. To be included, patients had to meet the International Headache Society diagnostic criteria for chronic or episodic migraine, have an average headache pain intensity of 5 out of 10 or greater on the pain numerical scale ( NPS) during the 10 weeks prior to enrollment in the program. and be dissatisfied with their current migraine treatment.
Patients were free to start, continue, or stop any other migraine treatment as recommended by their doctor as long as it was reported to the study team.
White against green
The one-way crossover design involved 10 weeks exposure to white light emitting diodes, for 1 to 2 hours per day, followed by a 2 week washout period, then 10 weeks exposure to green light emitting diodes (GLED ) for the same daily duration. The protocol involved the use of a light strip emitting an intensity between 4 and 100 lux measured at approximately 2 m and 1 m from a luxmeter.
Patients were instructed to use the light in a dark room, without falling asleep, and to participate in activities that did not require external light sources, such as listening to music, reading books, exercising. exercises or participation in similar activities. The minimum daily exposure of 1 hour, up to a maximum of 2 hours, was to be done in one sitting.
The primary outcome measure was the number of headache days per month, defined as days with moderate to severe headache lasting at least 4 hours. Secondary outcomes included a perceived reduction in the duration and intensity of the headache phase of migraine episodes assessed every 2 weeks with NPS, improvement in the ability to fall asleep and stay asleep, better ability to perform work and daily activity, better quality of life and reduced pain medication.
The researchers found that when patients with chronic migraine and episodic migraine were examined as separate groups, exposure to white light did not significantly reduce the number of headache days per month, but when the chronic migraine and episodic migraine groups were combined, there was a significant reduction. from 18.2 to 16.5 headache days per month.
On the other hand, the green light resulted in a significant reduction in headache days in both the separate groups (from 7.9 to 2.4 days in the episodic migraine group and from 22.3 to 9.4 days in the chronic migraine group) and combined (from 18.4 to 7.4 days).
“While some improvement in secondary outcomes was seen with white light emitting diodes, more secondary outcomes with significantly greater magnitude, including quality of life ratings, the McGill Pain Questionnaire, the headache impact test-6 and the five-level version of EuroQol A five-dimensional investigation with no reported side effects was observed with green LEDs, ”the authors reported.
“Using a non-pharmacological therapy such as the go-ahead can be of great help for a variety of patients who do not want or respond to medication,” said co-author Amol. M. Patwardhan, MD, PhD, in press release. “The beauty of this approach is the absence of associated side effects. As long as it improves sleep and other measures of quality of life, ”said Patwardhan, associate professor and vice president of research in the Department of Anesthesiology at the University of Arizona.
Better than white light
Asked to comment on the results, Alan M. Rapoport, MD, clinical professor of neurology at the University of California, Los Angeles, said research has shown for some time that exposure to green light has beneficial effects. in migraine patients. This study, although small, indicates that green light is more beneficial than white light and reduces headache days and intensity. “I think patients would be willing to go 1-2 hours a day on the go to reduce and improve their migraine with few side effects. A larger randomized trial should be done,” he said.
The study was funded by support from the National Center for Complementary and Integrative Health (in Ibrahim), the Comprehensive Chronic Pain and Addiction Center – University of Arizona, and the University of Arizona’s CHiLLI initiative. Ibrahim and a co-author have a patent pending with the University of Arizona for the use of green light therapy for the management of chronic pain. Rapoport is a past president of the International Headache Society. He is editor-in-chief of Headache and CNS Drugs, and editor-in-chief of Neurology Reviews. He reviews numerous peer-reviewed journals such as Cephalalgia, Neurology, New England Journal of Medicine, and Headache.
This article originally appeared on MDedge.com, which is part of the Medscape Professional Network.