Incidence and associations of poststroke epilepsy: the prospective South London Stroke Register

Abstract

Background and purpose: To describe the epidemiology and associations of poststroke epilepsy (PSE) because there is limited evidence to inform clinicians and guide future research.

Methods: Data were collected from the population-based South London Stroke Register of first strokes in a multiethnic inner-city population with a maximum follow-up of 12 years. Self-completed forms and interviews notified study organizers of epilepsy diagnosis. Kaplan-Meier methods and Cox models were used to assess associations with sociodemographic factors, clinical features, stroke subtype, and severity markers.

Results: Three thousand three-hundred ten patients with no history of epilepsy presented with first stroke between 1995 and 2007, with a mean follow-up of 3.8 years. Two-hundred thirteen subjects (6.4%) had development of PSE. PSE incidence at 3 months and 1, 5, and 10 years were estimated at 1.5%, 3.5%, 9.0%, and 12.4%, respectively. Sex, ethnicity, and socioeconomic status were not associations, but markers of cortical location, including dysphasia, visual neglect, and field defect, along with stroke severity indices at presentation, including low Glasgow Coma Scale, incontinence, or poor function on Barthel Index, were associated with PSE on univariate analysis. Young age was independently associated with PSE, affecting 10.7% of patients aged <65 years and 1.6% >85 years (P≤0.001) on 10-year estimates. Independent predictors of PSE also included visual neglect, dysphasia, and stroke subtype, particularly total anterior circulation infarcts. Dysarthria was associated with reduced incidence.

Conclusions: PSE is common, with risk continuing to increase outside the acute phase. Young age, cortical location, larger lesions, and hemorrhagic lesions are independent predictors.