Abstracts

Rationale: We prospectively examined changes in neuropsychological functioning in relationship to seizure control and epileptic syndrome for 36 months following onset in otherwise healthy children. Methods: We followed 209 children ages 6-14 years who had experienced a first recognized seizure and 144 sibling controls; the two groups did not differ on age or sex. Descriptions of seizures and seizure control were obtained from chart review and from interviews with parents at baseline, 9, 18, 27, and 36 months. Neuropsychological functioning was assessed an average of 2.8 months following the first recognized seizure and again 36 months later. Children completed a neuropsychological test battery that included well-standardized, reliable and valid measures of a broad spectrum of cognitive functions that formed four factors: Language, Verbal Memory & Learning, Processing Speed, and Attention/Executive/Construction (Byars et al, Epilepsia, 48(6):1067-1074,2007). Factor scores were based on standardized scores, which were corrected for age using the published norms for each test; higher scores reflect better performance on all factors. Epileptic syndrome was defined using ILAE criteria. Children were classified at 36 months into one of four groups: Sibling (n=143), No Recurrence (i.e., only one unprovoked seizure; n=56), Recurrent Seizure (i.e., additional seizures during at least one follow-up period but not at all follow-up periods; n=128), or Persistent (i.e., additional seizures reported at every follow-up period; n=25). Results: The Persistent Seizure Group showed the greatest decline on Processing Speed (p = .0001 overall; p≤ .04 compared to all other groups), Verbal Memory & Learning (p = .03 overall; p ≤ .05 compared to Sibling and No Recurrence Groups), and Attention/Executive/Construction (p = .03 overall; p = .02 compared to Sibling Group). In addition, the Recurrent Group scored lower than the Sibling Group on Processing Speed (p = .01). A similar pattern was observed on the Language factor, but this was not statistically significant (p > .05). There were no differences among the epileptic syndrome groups with regard to neuropsychological change (p > .05). Representative results are graphed in Figures 1 & 2. Conclusions: In children with onset of seizures during school-age years, inadequate seizure control is associated with declines in mental processing speed during the first three years following onset; persistent seizures, in particular, are associated with more pervasive neuropsychological declines, even in a high-functioning seizure population. Epileptic syndrome was not associated with neuropsychological declines, but this sample of children with school-age onset had relatively uncomplicated epilepsy without major neurological deficits. (Funded by NIH/NINDS R01 NS22416 to J. K. Austin)