Neonatal seizures and postneonatal epilepsy: a 7-y follow-up study

Abstract

Seizures are one of the most common symptoms of acute neurological disorders in newborns. This study aimed at evaluating predictors of epilepsy in newborns with neonatal seizures. We recruited consecutively 85 neonates with repeated neonatal video-electroencephalogram (EEG)-confirmed seizures between January 1999 and December 2004. The relationship between clinical, EEG, and ultrasound (US) data in the neonatal period and the development of postneonatal epilepsy was investigated at 7 y of age. Fifteen patients (17.6%) developed postneonatal epilepsy. Partial or no response to anticonvulsant therapy (odds ratio (OR) 16.7, 95% confidence interval (CI): 1.8-155.8, P = 0.01; OR 47, 95% CI: 5.2-418.1, P < 0.01, respectively), severely abnormal cerebral US scan findings (OR: 5.4; 95% CI: 1.1-27.4; P < 0.04), severely abnormal EEG background activity (OR: 9.5; 95% CI: 1.6-54.2; P = 0.01), and the presence of status epilepticus (OR: 6.1; 95% CI: 1.8-20.3; P < 0.01) were found to be predictors of epilepsy. However, only the response to therapy seemed to be an independent predictor of postneonatal epilepsy. Neonatal seizures seem to be related to postneonatal epilepsy. Recurrent and prolonged neonatal seizures may act on an epileptogenic substrate, causing further damage, which is responsible for the subsequent clinical expression of epilepsy.