Abstracts

Rationale: Many patients with new-onset focal epilepsies are first assessed in an emergency department (ED). Treatment decisions in the ED can influence likelihood of further seizure activity. Using prospective data from The Human Epilepsy Project (HEP), which follows patients with newly diagnosed focal epilepsy, we assessed the effect of seizure characteristics on ED decision-making. Methods: We assessed data from the first 175 participants enrolled in HEP. Four were excluded due to incomplete enrollment data. Patients with new-onset focal epilepsy seen within four months of treatment initiation were eligible to participate. Upon enrollment, patients completed a seizure diary documenting all prior seizures, which were classified using a standardized interview (DISCOVER) form. Based on clinical descriptions, seizures were categorized as disruptive seizures (DS) (motor activity or verbal output, including generalized tonic-clonic (GTCC)) or subtle seizures (SS) (primarily motor arrest or focal aware without motor). Medical records pertaining to initial diagnosis and treatment were reviewed. Parametric testing was used to compare normally distributed variables. Results: Baseline characteristics were similar between DS and SS groups. Patients with DS were more likely than patients with SS to seek evaluation in an ED after an initial seizure (9/94 (10%) with SS vs 53/71 (75%) with DS (p < 0.0001). Of these, 5/9 (55%) SS patients were identified in the ED as possible seizure, and one was started on an antiepileptic drug (AED), initiated after the patient had a GTCC seizure while in the ED. 48/53 (90%) of DS patients were identified as having had a seizure in the ED, and 12 were started on an AED. DS patients were therefore more likely to be correctly diagnosed after a first event (p = 0.0062). Eight patients with DS presented after >