Long-term outcomes of children with drug-resistant epilepsy across multiple cognitive domains.

Aim To simultaneously evaluate long-term outcomes of children with drug-resistant epilepsy (DRE) across multiple cognitive domains and compare the characteristics of participants sharing a similar cognitive profile. Method Participants were adolescents and young adults (AYAs) diagnosed with DRE in childhood, who completed a comprehensive neuropsychological battery evaluating intelligence, memory, academic, and language skills at the time of surgical candidacy evaluation and at long-term follow-up (4-11y later). Hierarchical k-means clustering identified subgroups of AYAs showing a unique pattern of cognitive functioning in the long-term. Results Participants (n=93; mean age 20y 1mo [standard deviation {SD} 4y 6mo]; 36% male) were followed for 7 years (SD 2y 4mo), of whom 65% had undergone resective epilepsy surgery. Two subgroups with unique patterns of cognitive functioning were identified, which could be broadly categorized as 'impaired cognition' (45% of the sample) and 'average cognition' (55% of the sample); the mean z-score across cognitive measures at follow-up was -1.86 (SD 0.62) and -0.23 (SD 0.54) respectively. Surgical and non-surgical patients were similar with respect to seizure control and their long-term cognitive profile. AYAs in the average cognition cluster were more likely to have better cognition at baseline, an older age at epilepsy onset, and better seizure control at follow-up. Interpretation The underlying abnormal neural substrate and seizure control were largely associated with long-term outcomes across cognitive domains.