Comorbidity of migraine and epilepsy in a Norwegian community

Studies on the comorbidity of migraine and epilepsy have shown conflicting results. We wanted to explore the epidemiological association between migraine and seizure disorders in a population-based material where case ascertainment was enhanced by individual specialist assessments. Information concerning migraine and seizure disorders was collected from 1793 participants in an interview-based survey in a circumscribed community. Mixed headache, with features both of migraine without aura and tension-type headache, was excluded from further analyses because of its ambiguous character (n = 137). Thus, data from 1656 participants were included in the study. The number of subjects with epilepsy was small, and a statistically significant association between migraine and the diagnosis of epilepsy was not found. There was a tendency to more active epilepsy in subjects with migraine (1.0%, 5/524), particularly for migraine with aura (1.8%, 3/168), compared with subjects without migraine (0.5%, 6/1132). Migraine was present in five of 11 subjects with active epilepsy (45%) and in four of 28 (14%) with epilepsy in remission (P = 0.09). An overall association between migraine and seizure disorders could not be demonstrated, but there was a tendency to more migraine in individuals with active epilepsy.