Predictors of intellectual functioning after epilepsy surgery in childhood: The role of socioeconomic status.

OBJECTIVE: The objective of this study was to evaluate the association between socioeconomic status and intellectual functioning in children with medically refractory epilepsy, before and after resective epilepsy surgery. Family environment is a strong contributor to cognitive development in children and has been recently shown to play a significant role in intellectual outcome after surgery in children with epilepsy.

METHODS: One hundred children who had undergone resective epilepsy surgery and completed preoperative and postoperative assessments of IQ as part of clinical care were included in the study. We evaluated the impact of epilepsy-related variables, income quintile, and residence location on IQ.

RESULTS: Greater improvements in IQ after surgery were associated with an older age at surgery (β=.235, p=.018). Higher IQ scores at follow-up were associated with an older age of seizure onset (β=.371, p<.001), older age at surgery (β=.356, p<.001), unilobar epileptogenic focus (β=.394, p<.001), and mesial temporal sclerosis (β=.338, p=.001) or tumor (β=.457, p<.001) in comparison with malformation of cortical development; age at seizure onset did not remain as a significant predictor in multivariable regression analysis. Income quintile, residence location, seizure control, and antiepileptic medication use were not significant predictors.

CONCLUSIONS: Epilepsy-related variables were the strongest predictors of IQ and postoperative change in IQ. We were unable to identify a significant association between IQ and socioeconomic status. Future research should evaluate the impact of multiple aspects of family environment.