COVID‐19 Vaccination and the Risk of Migraine Chronification: A Comparative Cohort Study of Vaccinated and Unvaccinated Patients With Episodic Migraine

INTRODUCTION: Headache is among the most frequently reported adverse events after COVID-19 vaccination, and patients with migraine often fear that vaccination will worsen their disease or accelerate the transition from episodic to chronic migraine. Controlled data comparing vaccinated and unvaccinated patients with migraine are scarce. METHODS: We conducted a comparative prospective cohort study of 60 adults with pre-existing episodic migraine, classified at enrolment as vaccinated (n = 30) or unvaccinated (n = 30) against COVID-19, at a single neuroscience clinic in Jeddah, Saudi Arabia, and followed for 6 months. Migraine status (episodic or chronic, per ICHD-3) was assessed at 3 and 6 months. Between-group chronification was compared using Fisher's exact test with odds ratios (ORs) and 95% confidence intervals (CIs); patient-level transitions were also examined. No a priori sample-size calculation was performed. RESULTS: There were no statistically significant baseline differences between groups in age (30.3 ± 5.07 vs. 30.5 ± 4.46 years; p = 0.87), sex (p = 0.78), or preventive medication (p = 0.58). Provisional chronic-frequency status was recorded in 5/30 vaccinated versus 11/30 unvaccinated patients at 3 months (OR 0.35, 95% CI 0.10-1.16; p = 0.14), and chronic migraine in 3/30 versus 6/30 at 6 months (OR 0.44, 95% CI 0.10-1.97; p = 0.47). All such transitions occurred by 3 months, with no new cases between 3 and 6 months; the confidence intervals were wide and included no difference. CONCLUSIONS: In this small observational cohort, no statistically significant association was detected between COVID-19 vaccination and migraine chronification. The wide confidence intervals preclude firm conclusions regarding either harm or benefit, and larger, adequately powered studies are needed.