Risk of Seizure Recurrence Following a First Unprovoked Seizure in Childhood

Background: There is still a question whether first seizure leads to epilepsy. Several risk factors have been reported in this relation. This study was undertaken to determine the risk of recurrence after a first unprovoked seizure in children. Methods: In a prospective study between December 2003 and December 2005, 156 children who presented with a first unprovoked seizure were enrolled and followed for at least 18 months. Potential predictors of recurrence were compared, using the Cox Proportional Hazard model in a univariable and multivariate analysis. Survival analysis was performed, using the Kaplan-Meire curves. Results: Seventy two children (46.2%) experienced subsequent seizures. The cumulative risk of seizure recurrence was 28.8%, 41.7% and 46.2% at 6, 12, and 24 months following the first seizure, respectively. The median time for repeated seizure was 4 months while 62.5% of the recurrence occurred within 6 months, 88.9% within 1 year and 100% till the end of the second year. On multiple analysis, risk factors for resumption of seizure consisted of abnormal electroencephalography (EEG), seizure during sleep, abnormal brain imaging and history of perinatal problems. On univariable analysis, abnormal EEG, abnormal imaging (remote etiology of seizure), history of neonatal problems, previous febrile seizure, and family history of afebrile seizure increased the risk of recurrence. Conclusion: The study revealed that the risk of seizure recurrence in our patients was relatively high. Those who had abnormal electroencephalography, past history of prenatal problems, remote etiology for seizure, abnormal brain imaging, and seizure during sleep were at greater risk for recurrence of seizure.