Green light significantly reduces headache frequency in migraine: Study

Though the mechanism is not completely understood, "The intrinsically photosensitive retinal ganglion cells (IPRGCs) project to the midbrain and are involved in triggering photophobia in migraine patients. It is, therefore, possible that GLED is mediating its effect through the IPRGCs." said the team.

Migraine is a multiphasic neurological disorder associated with multiple symptoms including moderate to severe headache, photophobia, phonophobia, nausea, and vomiting. Patients suffering from migraines frequently report decreased quality of life, decreased work productivity, higher rates of work absences, more use, and overuse of both over-the-counter and prescription medications including opioids, and more healthcare usage including emergency department visits.

Current strategies to manage migraines rely on acute and preventive therapies as well as non-pharmacological approaches. Despite the above pharmacological strategies for managing migraines, some patients do not achieve adequate pain control or may not tolerate their side effects (16,17). Also, some patients may prefer non-pharmacological approaches to manage their pain. Therefore, offering a non-pharmacological therapeutic option could be useful as a standalone or as a complement to pharmacotherapies.

Given the safety of green light-emitting diode, a research team under Laurent F Martin, evaluated green light as a potential therapy in patients with episodic or chronic migraine.

The research team recruited (29 total) patients, of whom seven had an episodic migraine and 22 had a chronic migraine. A one-way cross-over design consisting of exposure for 1–2 hours daily to the white light-emitting diodes for 10 weeks, followed by a 2-week washout period followed by exposure for 1–2 hours daily to green light-emitting diodes for 10 weeks was designed. Patients were allowed to continue current therapies and to initiate new treatments as directed by their physicians.

Measured outcomes consisted of patient-reported surveys. The primary outcome measure was the number of headache days per month. Secondary outcome measures included patient-reported changes in the intensity and frequency of the headaches over two weeks and other quality of life measures including the ability to fall and stay asleep, and ability to perform work. Changes in pain medications were obtained to assess potential reduction.

On data analysis, the following key facts emerged.

• When seven episodic migraine and 22 chronic migraine patients were analyzed as separate cohorts, white light-emitting diodes produced no significant change in headache days in either episodic migraine or chronic migraine patients.
• Combining data from the episodic migraine and chronic migraine groups showed that white light-emitting diodes produced a small, but statistically significant reduction in headache days from (days SEM) 18.2 1.8 to 16.5 2.01 days.
• Green light-emitting diodes resulted in a significant decrease in headache days from 7.9 1.6 to 2.4 1.1 and from 22.3 1.2 to 9.4 1.6 in episodic migraine and chronic migraine patients, respectively.
• While some improvement in secondary outcomes was observed with white light-emitting diodes, more secondary outcomes with significantly greater magnitude including assessments of the quality of life, Short-Form McGill Pain Questionnaire, Headache Impact Test-6, and Five-level version of the EuroQol five-dimensional survey without reported side effects were observed with green light-emitting diodes.

"Green light-emitting diodes significantly reduced the number of headache days in people with episodic migraine or chronic migraine. Additionally, the green light-emitting diodes significantly improved multiple secondary outcome measures including quality of life and intensity and duration of the headache attacks. As no adverse events were reported, the green light-emitting diodes may provide a treatment option for those patients who prefer nonpharmacological therapies or may be considered in complementing other treatment strategies. The limitations of this study are the small number of patients evaluated. The positive data obtained support implementation of larger clinical trials to determine possible effects of green light-emitting diode therapy." concluded the team.

For the full article follow the link: 10.1177/0333102420956711

PRIMARY SOURCE: Cephalalgia