Supplementary Material for: The Association Between Allergic Diseases and Migraine: A Systematic Review and Meta-Analysis

Introduction: This study aims to systematically review and summarize epidemiological evidence on the relationship between allergic diseases and migraine outcomes.
Methods: This meta-analysis, which was registered with PROSPERO (CRD420250656492), employed data from PubMed, Embase, the Cochrane Library, and references from the studies included in the review. The search encompassed literature from the inception of these databases through Feb 24, 2025. We included observational studies investigating the association between allergic diseases and migraine. The risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS). Pooled odds ratio (OR) with 95% confidence interval (CI) were calculated using a random-effects model.
Results: A total of 10 studies encompassing 14,952,953 participants were included. The overall risk for migraine in patients with allergic diseases was 1.52 (95% CI: 1.40–1.65). Specifically, the meta-analysis revealed an OR for atopic dermatitis of 1.27(1.17–1.38), 1.49 (95% CI 1.32–1.68) for asthma, 2.16 (95% CI 1.43–3.24) for allergic rhinitis, and 1.74 (95% CI 1.43–2.10) for allergic conjunctivitis.
Conclusion: The current meta-analysis suggests that allergic diseases is associated with an increased risk of developing migraines. However, further large-scale prospective cohort studies are required to validate the proposed association, considering the considerable heterogeneity observed in our analyses.