Allergic Conjunctivitis and the Associated Risk of Migraine Among Children: A Nationwide Population-based Cohort Study

Abstract

ABSTRACTPurpose: To investigate the risk of migraine in children with allergic conjunctivitis (AC).Methods: In this population-based cohort study, 309 138 children with AC and 309 138 non-AC controls were included between 2000 and 2007. By 2008 end, the incidences of migraine in both cohorts, and the AC-to-non-AC cohort hazard ratios (HRs) were measured.Results: The incidence of migraine during the study period was 1.92-fold higher in the AC cohort than in the non-AC cohort. The risk was greater for boys with AC and children aged <6 years. The mean time-interval between physician-diagnosed AC to physician-diagnosed migraine was 3.67 years (SD = 2.19).The risk of migraine development in the AC cohort increased with follow-up time and was highest during 4–5 years after AC diagnosis. The children with AC more likely had migraine without than with aura.Conclusions: Children with AC had a higher incidence and subsequent risk of migraine.