Prevalence of genuine epilepsy among adult emergency patients with an episode of unconsciousness

Objective: Loss of consciousness (LOC) is caused by a variety of conditions including epileptic, cardiac, psychiatric, and autonomic disorders. We inv estigated the prevalence of presenting attacks of genuine epilepsy among pa tients of Emergency Department and Department of Cardiology evaluated for a n episode of LOC with or without a convulsion. Patients and methods: We ret rospectively studied 371 adults presenting to the Emergency Department and Department of Cardiology of our hospital from 1991 to 1999 with a chief com plaint of an episode of LOC with or without a convulsion. Ages ranged from 15 to 78 years. Patients were free of severe chronic illnesses, drug abuse, and alcoholism. LOC was considered to represent genuine epilepsy either wh en the interictal electroencephalogram (EEG) showed epileptiform discharges in the absence of imaging abnormalities, or when both the EEG and imaging studies were unrevealing but one or more previous attacks had occurred and administration of an anticonvulsant prevented subsequent attacks. Results: Patients included 302 patients without a convulsion, and 69 patients with a convulsion. Of the former, 14 subjects had epileptiform discharges on EEG, and three subjects had no epileptiform discharges but had three or four at tacks of LOC that were abolished by anticonvulsant therapy. Of the 69 patie nts with a convulsion, seven had epileptiform discharges, and 12 had two to five attacks, no epileptiform discharges, and a response to anticonvulsant therapy. Conclusions: The prevalence of presenting attacks of genuine epil epsy in 371 adult patients with an episode of LOC was remarkably high (9.7% : 36 subjects). (C) 2001 Elsevier Science B.V. All rights reserved.