Glaucoma Risk Associated With Calcitonin Gene–Related Peptide Inhibitor Use in Migraine

BACKGROUND AND OBJECTIVES: Migraine has been linked to an increased risk of glaucoma, and our study aims to assess the temporal association between calcitonin gene-related peptide inhibitors (CGRPi) and the risks of glaucoma in individuals with migraine. METHODS: This multinational retrospective cohort study included adults diagnosed with migraine who received migraine preventive medications in 2018-2024. Participants were categorized into the CGRPi group (erenumab, fremanezumab, galcanezumab, eptinezumab, atogepant, or rimegepant) and non-CGRPi group (valproate, topiramate, flunarizine, candesartan, lisinopril, metoprolol, propranolol, nadolol, amitriptyline, and venlafaxine). Crossovers were not allowed, and the non-CGRPi group included only individuals who never used CGRPi. The CGRPi and non-CGRPi groups were propensity score matched in a 1:1 ratio and were followed for up to 3 years to monitor the occurrence of incident glaucoma. The Cox proportional hazards model was used to compare the risk of glaucoma between CGRPi and non-CGRPi users, with results reported as hazard ratios (HRs) and 95% CIs. RESULTS: A total of 73,644 individuals were included in the final analysis. Compared with non-CGRPi users, CGRPi users experience a lower risk of glaucoma development (HR 0.75; 95% CI 0.61-0.92) within 3 years since its first prescription. Individuals using CGRPi also exhibit a reduced risk of glaucoma compared with those using topiramate (HR 0.73; 95% CI 0.59-0.90), valproate (HR 0.54; 95% CI 0.35-0.83), propranolol (HR 0.76; 95% CI 0.59-0.98), metoprolol (HR 0.76; 95% CI 0.59-0.98), lisinopril (HR 0.49; 95% CI 0.38-0.62), amitriptyline (HR 0.69; 95% CI 0.54-0.89), and venlafaxine (HR 0.68; 95% CI 0.50-0.91). In the analysis that further classified participants based on the specific CGRPi used, only users of monoclonal antibody CGRPi show a reduced risk of glaucoma compared with non-CGRPi users (HR 0.77; 95% CI 0.61-0.98). The reduced risk of glaucoma associated with CGRPi is also observed in older adults, women, and those with chronic migraine or migraine without aura. DISCUSSION: Among adults with migraine receiving preventive treatment, systemic use of CGRPi, particularly monoclonal antibody CGRPi, is associated with a reduced risk of glaucoma compared with the use of other migraine preventive medications. CLASSIFICATION OF EVIDENCE: This is a Class II study demonstrating that CGRPi users with migraine have a lower risk of incident glaucoma when compared with non-CGRPi users with migraine.