Abstracts

Rationale: Seizures are occasionally followed by Post-Ictal Headache (PIH). It has been previously described that postictal headaches are more likely after epileptic seizures (ES) and less likely after non-epileptic spells(NES). They have been studied in depth in patients with medically refractory partial epilepsy and have been well known to follow GTCS. It has been argued that this is an often-ignored symptom that is of lateralizing value. Pain is described as a fifth vital sign and with the intent to better understand the pain suffered during an EMU admission, we attempted to study the characteristics of headache in patients undergoing epilepsy monitoring. In this study, we analyze the relationship between headache phenotype and seizure characteristics using direct observation in an epilepsy-monitoring unit. To our knowledge this is the first study to be conducted in an inpatient directly observed setting with a unique cohort in contrast to outpatient clinic based surveys. Methods: After local IRB approval, the study was conducted from May 1, 2013 to April 30, 2014 and attempted to recruit all consecutive admissions to the adult EMU. There were 348 total elective admissions with 323 unique patients. Only 57 patients agreed to participate in this prospective observational study. Characteristics of the PIH were obtained by direct questioning by nursing staff involved in routine clinical care of the patient and the EEG with video was interpreted by the attending epileptologists. Results: All 57 patients were included in the analysis. 22 patients(38.5%) had NES with normal EEG and normal MRI. Subsequent to NES 14 patients(63%) suffered with PIH. 4 patients(18%), experienced a migraine headache and 10 (71%) described a dull diffuse tension type headache. 29 patients (50%) did not suffer an event during their hospitalization. While many of them had headaches by history and interictal epileptiform discharges, a clear episode was not captured in the EMU. Historically, these patients were more likely to describe an interictal migraine phenotype headache. Patients with migraine headaches (9) were more likely to have abnormal MRI findings (8 / 88%) than those without headache or non-migraine headaches. Only 6 patients in our cohort suffered with seizures during the stay. Conclusions: Postictal headache can occur commonly after non-epileptic events. While a migraine type PIH can occur with both ES and NES, non-descript or tension type headache phenotype is more likely to be associated with NES. A very high correlation of abnormal MRI findings in patients with migraine phenotype headache was an intriguing finding since migraines are typically associated with normal imaging. It may be that patients with migraine headaches and abnormal imaging are more likely to be referred to an EMU. A major limitation of the study is the small proportion (17%) of patients who agreed to participate in this study. A large study should be undertaken to understand the impact of PIH, on the quality of life of the patient, the associated disabilityand the comparative efficacy of different treatments options for post ictal headache.