Primary headache disorders in epileptic adults

Background Epilepsy and primary headache disorders are two relatively common neurological disorders and their relationship is still a matter of debate. We aimed to estimate the prevalence and clinical features of primary headache disorders in patients with epilepsy. Methods 62 subjects aged ≥ 18 years were recruited from the hospital’s neurology outpatient clinic in the period from January to April 2018. The subjects were further divided into two equal groups, epileptics and non-epileptics. They underwent a semi-structured interview including the ILAE 2017 epilepsy classification and the ICHD III-beta criteria for headache. Patients' demographic data and clinical characteristics of epilepsy and headache and temporal relationships between them were assessed. Patients who experienced headaches were grouped based on the type of headaches and on whether their headaches occurred in the pre-ictal, post-ictal or inter-ictal period. Results Primary headache disorders were more common in epileptic group (61.3%) than the non-epileptic group (32.2%) ( p = 0.021). The tension-type headache was the most common (45.2%) followed by migraine-type headache (12.9%) in the epileptic group. Post-ictal headache was the most common type (29%). Inter-ictal headaches were significantly related to "focal to bilateral tonic–clonic" seizures ( p = 0.046). The prevalence of headache among patients on polytherapy (69.2%) was higher than that of patients on monotherapy (52.9%). Conclusions In this study, headache was more common in epileptic patients. TTH was the most represented type of headache in patients with epilepsy. Headache occurred in patients with epilepsy most frequently during the post-ictal period.