The developing brain is more likely to seize after a stroke.

Commentary Although strokes occur in approximately 3.8 per 100,000 children (1, 2) and are considered a cause of epilepsy, there is limited data on seizure incidence after pediatric strokes. In addition, factors associated with an increased risk are not well characterized. Unlike adults among whom seizures are relatively infrequent (3–5% cumulative incidence) (3, 4), estimates among children vary ranging from 7 to 29% (5–7). Prior studies are limited by variable duration of follow-up and lack of population-based data. Understanding the risk of remote seizures after pediatric stroke is important as affected children may require closer observation and could be targets for seizure and epilepsy prevention. In the present study, Fox and colleagues aimed to determine incidence rates of remote seizures and predictors of epilepsy among a population-based cohort of children with stroke. A retrospective analysis of remote seizures and epilepsy within a cohort of children with stroke enrolled at Kaiser Permanente Northern California (KPNC) was performed. The original study population included all children through age 19 enrolled at KPNC between January 1993 and December 2007 (n = 2.5 million). The stroke cohort consisted of children with a documented presentation of a stroke who had imaging showing a focal infarct or hemorrhage in a location consistent with clinical presentation. Neonatal strokes and children who died during the stroke hospitalization were excluded. From the original cohort, 322 children had a nonneonatal stroke and 17 died acutely, leaving 305 for inclusion in this analysis: 140 had an ischemic stroke and 165 had a hemorrhagic stroke. The primary outcome was remote seizure. Records were searched for International Classification of Diseases ninth revision codes relating to seizure and epilepsy in inpatient and outpatient databases. Pharmacy records were searched for antiepileptic drugs (AEDs). Cases were reviewed independently by two child neurologists, and a third when necessary to confirm the diagnosis of remote seizure. Remote seizure was defined as at least one documented unprovoked seizure occurring >30 days after stroke. Active epilepsy was defined as at least one unprovoked remote seizure and ongoing AED treatment, or less than 6 months seizure-free off AEDs at time of last follow-up visit. Analyzed predictors included age, acute seizure (seizure at time of clinical presentation), neurologic deficit at hospital discharge, stroke location, stroke type (intraparenchymal hemorrhage, subarachnoid hemorrhage/ intraventricular hemorrhage, arterial ischemic stroke, venous sinus thrombosis), and laterality. Survival analysis was used to determine incidence rates and cumulative risk of remote …