Abstracts

Previous reports have documented coexistence of obstructive sleep apnea (OSA) and epilepsy, as well as the effect of treating sleep apnea on seizure frequency and excessive daytime sleepiness. Our objective was to determine the prevalence of sleep related symptoms in a population with medically refractory epilepsy. This is a retrospective chart review study on an outpatient population who were seen at a tertiary epilepsy center within the Kaleida Health System at Buffalo, NY. From all the patients who were seen for seizure disorder, those with medically intractable epilepsy were selected. All of the patients had completed the same questionnaire about measures of sleep-related breathing problems, sleep disturbance, excessive daytime sleepiness, snoring, and hypertension. Other data including seizure frequency, seizure duration and type and number of anti-epileptic drugs were also extracted from the patient charts and entered into a database. Of 84 adult patients with a diagnosis of epilepsy, 28 qualified for medically intractable epilepsy by the study criteria. Fifteen subjects (53%) reported symptoms of sleep disturbance including 14 (50%) with excessive daytime sleepiness, and 11 (40%) with snoring. Five patients (18%) had sleep disorders confirmed by polysomnography. Eight subjects (28%) had hypertension. Subjects with sleep disturbance were more likely to be younger and female. Although there was no statistical difference between the two groups with regards to the type and number of antiepileptic drugs and seizure localization (temporal versus extra-temporal), the subjects with sleep disturbance tended to have a higher seizure frequency per month, and were more likely to have their first seizures at a younger age (Student T-test p[lt]0.05). The high concordance between sleep disturbance and seizure intractability suggests that sleep disorders may play an important role in seizure exacerbation. The presence of features of sleep disturbance in patients with medically intractable epilepsy should alert the clinician to the possibility of an underlying sleep disorder contributing to the therapeutic resistance. Further studies are needed to clarify the mechanisms by which sleep disturbance contributes to seizure intractability.