Can Migraine Drugs Lower Glaucoma Risk? CGRP Inhibitors Show Potential in New Study

A new study suggests that people who take certain migraine prevention drugs may also protect their eyesight. The research found that patients using a class of medications called CGRP inhibitors had a lower chance of developing glaucoma, a leading cause of blindness.

The study, published in the journal Neurology, looked at health records from more than 74,000 migraine patients. Researchers found that those who took CGRP inhibitors for migraine prevention had a 25% lower risk of getting glaucoma within three years compared with people who used other types of migraine medications. The findings were reported by Dr. Chien-Hsiang Weng of Brown University and his team.

Only a specific type of CGRP inhibitor—monoclonal antibody drugs—was linked to the lower glaucoma risk. These include fremanezumab (brand name Ajovy), galcanezumab (Emgality), eptinezumab (Vyepti), and erenumab (Aimovig). Two other CGRP-related drugs, atogepant (Qulipta) and rimegepant (Nurtec), did not show the same benefit.

“Glaucoma is a leading cause of blindness, and evidence has linked migraine with an increased risk of glaucoma, with both conditions affecting the capacity of the blood vessels in the brain to alter blood flow in response to stimuli,” Weng said in a statement. “Since CGRP inhibitors help regulate blood vessel contraction and inflammation in the nervous system, there has been hope that these drugs could benefit eye health in people at risk of glaucoma.”

The researchers believe that CGRP inhibitors may lower glaucoma risk by helping to control pressure inside the eye and by reducing inflammation in the nervous system. They explained that the blood-aqueous barrier in the eye plays a major role in how fluid is produced inside the eye. Animal studies have shown that giving CGRP directly into the eye can disrupt this barrier and increase intraocular pressure, which raises glaucoma risk.

“This hypothesis is supported by our findings, which show a reduced risk of ocular hypertension in the CGRP inhibitor group compared with the non-CGRP inhibitor group,” the authors wrote. “In addition to IOP modulation, CGRP contributes to inflammatory signaling cascades in both migraine and ocular tissues.” They added that studies have shown that inflammation can speed up the loss of retinal ganglion cells and damage the optic nerve, even when eye pressure is normal.

To conduct the study, Weng and his team looked at electronic health records from the TriNetX global network, which mostly included data from the United States. They analyzed records of 73,644 adult migraine patients who received preventive medications from May 2018—when the first CGRP blocker, erenumab, was approved by the FDA—through 2024.

The researchers split patients into two groups. One group took CGRP inhibitors, including erenumab, fremanezumab, galcanezumab, eptinezumab, atogepant, or rimegepant. The other group took non-CGRP migraine drugs, such as valproate, topiramate, flunarizine, candesartan, lisinopril, metoprolol, propranolol, nadolol, amitriptyline, or venlafaxine.

All patients had an initial prescription for a migraine preventive drug and at least one refill within six months. People in the non-CGRP group never used CGRP inhibitors. The two groups were matched on age, health conditions, and other factors. Each group had 36,822 patients. In the CGRP inhibitor group, the average age was 42.5 years, and patients were followed for an average of 1.77 years. In the non-CGRP group, the average age was 42.6 years, and follow-up averaged 1.97 years.

During the study, 0.42% of people in the CGRP inhibitor group developed glaucoma, compared with 0.61% in the non-CGRP group. The lower risk held up even when CGRP inhibitors were compared specifically with beta-blockers, a common class of migraine drugs. The researchers also found that migraine patients taking CGRP inhibitors had a lower risk of ocular hypertension, or high eye pressure, but not a lower risk of primary open-angle glaucoma.

The researchers noted some limits to the study. They said that factors like how severe a patient’s migraines were or how well they followed their medication routine could have affected the results. Also, the study lacked detailed eye exam data, such as repeated pressure measurements or optic nerve scans, which made it impossible to fully analyze how CGRP inhibition might affect eye pressure.

“Further studies are needed to confirm these results, but the findings may help us better understand both migraine and glaucoma,” Weng said.

Source: MedPage Today