Abstracts

Rationale: To assess the percentage of those who develop stroke-related epilepsy and become refractory to antiepileptic medications Methods: We performed a population-based, retrospective cohort study between April 1, 2003 and March 31, 2011 to identify individuals with medically-refractory, stroke-related epilepsy. Linked administrative healthcare databases from the Canadian Institute for Health Information, the National Ambulatory Care Reporting System, the Registry of the Canadian Stroke Network and the Ontario Health Insurance Plan were used to identify all stroke patients in Ontario, Canada and those who subsequently developed epilepsy. Medically-refractory epilepsy patients were distinguished based on the recent ILAE definition. Those with a history of seizures, previous antiepileptic drug use, a brain tumor or previous epilepsy surgery were excluded. Patient demographics, associated medical conditions, prior health care utilization, mortality and emergency department visits were investigated. Results: Among the 19,138 stroke patients identified for the study, 210 (1.1%) developed epilepsy. On average, those who developed epilepsy were younger, scored a higher Charlson index, and had higher rates of fractures, atrial fibrillation, and health care utilization. Regarding outcomes, 27 (12.9%) of these patients developed medically-refractory epilepsy and their rate of all-cause, five year mortality, was 46.2%.  Conclusions: Although it is common knowledge that a third of those with focal epilepsy, may become medically-intractable, only 13% of those with stroke-related epilepsy experienced that outcome Funding: This study was supported by the Institute for Clinical Evaluative Sciences (ICES) Western site. ICES is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC). Core funding for ICES Western is provided by the Academic Medical Organization of Southwestern Ontario (AMOSO), the Schulich School of Medicine and Dentistry (SSMD), Western University, and the Lawson Health Research Institute (LHRI). The opinions, results, and conclusions are those of the authors and are independent from the funding sources. No endorsement by ICES, AMOSO, SSMD, LHRI, or the MOHLTC is intended or should be inferred.