Abstract 41: Acute Seizures and Neurologic Deficits Predict Epilepsy After Pediatric Stroke
Background: Epilepsy may be frequent after pediatric stroke. However, current incidence estimates are from tertiary referral centers and vary widely, and little is known about its risk factors.
Methods: We performed a population-based study of epilepsy within a cohort of children with stroke (birth-20 years) enrolled in a Northern California integrated health care system, from January 1993 through December 2007, to determine epilepsy incidence rates and predictors. Children with symptomatic ischemic and hemorrhagic stroke surviving to hospital discharge were included in the analysis. Seizures were identified using clinical databases, and epilepsy diagnoses were confirmed by independent record review by two neurologists with arbitration by a third. Based on International League Against Epilepsy proposed guidelines, epilepsy was defined as a confirmed unprovoked seizure > 30 days after stroke. Survival analysis was used to determine rates and predictors of epilepsy after stroke. Using multivariable analysis, hazard ratios (HR) were adjusted for gender, age (neonatal versus later childhood), stroke subtype (ischemic versus hemorrhagic), outcome at hospital discharge, and acute seizures at the time of stroke.
Results: From an initial study population of 2.4 million children, 371 children with stroke were included. Of these, 110 cases were neonatal and 261 were later childhood; 226 were ischemic and 145 were hemorrhagic. At stroke ictus, 36% had an acute seizure, and 66% had a neurologic deficit at hospital discharge. Median length of follow-up was 4.5 years (IQR 1.9-8.6). Post-stroke epilepsy occurred in 89 subjects. The average annual incidence rate of epilepsy was 6.4% (95% CI 5.2%, 8%), with a 5-year cumulative risk of 25% (95% CI 20%, 30%) and 10 year cumulative risk of 40% (95% CI 32%, 51%) (Figure). Predictors of epilepsy included neurologic deficit at hospital discharge (HR 1.8, 95% CI 1.07-3) and seizure at stroke ictus (HR 4.1, 95% CI 2.6-6.5) (Figure), but not gender, age or stroke subtype.
Conclusions: Epilepsy is common after stroke in children. Those with seizures at onset of stroke are at particularly high risk, in keeping with animal models of epileptogenesis and recent studies of human neonatal hypoxic ischemic brain injury. Future studies are needed to further identify children at greatest risk for post-stroke epilepsy.
- © 2012 by American Heart Association, Inc.