Abstracts

Rationale: An accurate diagnosis of epilepsy is essential to avoid a number of deleterious consequences including unnecessary exposure to AEDs, the stigma of epilepsy and various restrictions regarding driving and employment. A variety of events can mimic seizures, and the imitators of epilepsy differ across age groupsMethods: In this prospective study, 28 neurologists from across Lebanon referred their patients (> 6 month of age) with one or more suspected new onset unprovoked seizures to the American University of Beirut where they underwent an evaluation that included detailed description of the spells, full physical and neurological examinations, 3-hour sleep- deprived video-EEG study, epilepsy protocol MRI, bone densitometry, and quality of life questionnaire. Consequent to this evaluation, patients were stratified into one of four categories: 1) newly diagnosed epilepsy; 2) single unprovoked seizure; 3) non-epileptic events (NEE) and 4) Uncertain. In this study, we evaluated the percentage of patients in category 3 and stratified the frequencies and types of events according to ageResults: Of the first 254 consecutive patients enrolled in the first 24 weeks of the study, 167 (66%) were children (younger than 18 years) and 87 patients (34%) were 18 years of age or older (adults). After EEG and/or MRI, the distribution of patients among the 4 diagnostic categories was as follows: 62% in category 1, 10% in category 2, 18% in category 3, and 10% in category 4. In the NEE category (n=46, M/F=27/19) the mean age at presentation was 13.7 years (0.5-81 years) and only 10 patients were 18 years of age or older. The most frequent diagnoses were non-epileptic psychogenic spells (NEPS), syncope, breath holding spells, and habitual staring spells. The frequency of NEEs was significantly higher in patients younger than 18 years of age (36/167; 22%) compared to older patients (10/87; 11%) (P= 0.048). The frequency of NEPS varied amongst age groups and was significantly more represented amongst adults (60%) compared to children (19%) (P=0.02). The diagnosis of NEPS was confirmed in all 13 cases by inducing a habitual spell by hyperventilation or subcutaneous injection of saline during EEG recording. There was no gender difference for the diagnosis of NEPS in either age group. A logistic regression analysis revealed that amongst patients in the 20-45 years age group with NEE, there is a greater than 85% probability that the event represent a NEPS. Of note, 12 of the 46 patients (26%) in the NEE category were already initiated on AED treatment at the time of their referral Conclusions: The incidence of NEE in this prospective study of patients with suspected new onset seizures is 18%. Non-epileptic events are more commonly noted in the pediatric age group where a large number of disorders can mimic epilepsy. In the adult population, NEPS are significantly more common than in pediatric age group. In conjunction with syncope, NEPS account for the majority of non-epileptic events in this age group