Seizure Scoring System and Neurodevelopmental Outcomes in Very Low Birth Weight Infants with Neonatal Seizures

Abstract

Purpose: To evaluate the utility of seizure scoring system in the prediction of neuro­ developmental outcomes in very low birth weight (VLBW) infants who presented with neonatal seizures. Methods: A retrospective review was performed in VLBW infants who were treated with antiepileptic drugs (AED) for the control of neonatal seizures. A total of 25 infants who survived and were followed­up for at least 2 years of age were included. A new seizure scoring system (the composite score 0­8) was constructed by choosing the following variables: onset, response to the AED, presence of status epilepticus, seizure types and EEG findings including background activity and epileptiform discharges. Neurodevelopmental outcomes were graded from 1 to 5 based on the developmental status and the neurologic abnormalities assessed at 18 to 24 months of postconceptional age. Risk factor analyses for predicting unfavorable outcomes (grade 3­5) versus favorable outcomes (grade 1­2) were performed. Results: Compared to favorable outcome group (n=11), unfavorable outcome group (n=14) had higher incidence of subtle or generalized tonic­type seizures, the abnormal EEG background activity and poor response to AED. The composite seizure score was significantly higher in the unfavorable outcome group (3.2±0.7) than in the favorable outcome group (1.2±1.2) and it significantly correlated with the neurodeve lopmental grading (P<0.001). In multivariate analysis, abnormal MRI findings at term and the composite seizure score were significant risk factors for unfavorable outcomes. Conclusion: In VLBW infants with neonatal seizure, the proposed seizure scoring system was a simple and useful predictor of long­term neurologic outcomes.