Frequency and Characteristics of Interictal and Postictal Headaches in Patients with Epilepsy

Abstract

Purpose: Patients with epilepsy often have headaches. It has been reported that some of these headaches have the same characteristics as migraine headaches and that a common etiology for migraine and epilepsy may exist. However, this supposition is still controversial, partly because there have been few studies on the relation between epilepsy and headaches. To address this issue, we investigated the frequency and characteristics of headaches independent of seizures (interictal headaches, 1Hs) and after seizures (postictal headaches, PHs) among a large number of patients. We also evaluated the associations between these headaches and other clinical features of the epilepsy. Methods: Two‐hundred and fifty‐six (1I1 male and 145 female; aged 13–82 years; mean, 41 years) patients with epilepsy who attended Hokkaido University Hospital were questioned by epileptologists using a questionnaire. The questionnaire addressed frequency, characteristics, duration, severity, and accompanying symptoms of IHs and PHs. Medical charts were reviewed for each patient, and we analyzed the sex, age, age at onset of epilepsy, duration and classification of epilepsy, type and frequency of seizures, and family history of headaches. Results: One‐hundred and twenty‐four (48%) patients had IHs. Among those patients, 80 (65%) were female patients. In contrast, among those with no IHs, 65 (49%) were female patients (p < 0.05). The mean age of those with IHs was 38 years and that of the patients with no IHs wab 45 years (p < 0.05). No significant difference was found for age at onset of epilepsy, duration and classification of epilepsy, or type and fequency of seizure between those patients with or without IHs. Thirty‐six (29%) patients with IHs had a family history of headaches as compared with only 21 (16%) patients in the group with no IHs (p < 0.05).Among the patients with IHs, 53 (43%) patients had pounding characteristics for their headaches; the frequency was daily in seven (6%) patients, weekly in 25 (20%), monthly in 51 (41%). and yearly in 35 (28%); the severity was mild in 70 (56%) patients, moderate in 39 (32%), and severe in 15 (12%); 33 (27%) of these patients had accompanying symptoms. PHs occurred in 89 (35%) patients. There was no difference in any clinical factors between the patients with or without PHs. Thirty‐five (35%) patients had pounding characteristics: the severity was mild in 34 (38%) patients, moderate in 29 (33%), and severe in 34 (38%); 56 (33%) of these patients had accompanying symptoms. Forty‐seven (38%) patients had both IHs and PHs. Of these, 22 patients had IHs and PHs with common characteristics. Conclusions: In this study, the frequency of both IHs (48%) and PHs (35%) was similar to that found in studies by other researchers (36 64% and 13–51%, respectively). However, migrainous features (pounding characteristics, moderate to severe pain, and accompanying symptoms such as nausea, photophobia and/or phonophobia) were fewer in this study than those found in other studies from the United States and Europe. This finding may be due to racial difference (is., the low prevalence of migraine among Asians). Considering the higher frequency of a family history of headaches among the patients with IHs and the absence of any difference in the clinical features of epilepsy between those patients with or without IHs, IHs may be related to a genetic susceptibility to headaches and migraines. We found few common characteristics between IHs and PHs. This finding suggests that mechanisms that trigger IHs and PHs are different.