Abstracts

Children with chronic epilepsy often exhibit cognitive impairment; some show decline, especially with early age of onset, persistent seizures, and/or toxic levels of some antiepileptic drugs (Bourgeois et al., 1983; Rodin, Schmaltz, [amp] Twitty, 1986). One study suggests that children might be more susceptible than adults to the effects of persistent seizures (Bjornaes et al., 2001). These studies have been limited to IQ. A study of academic achievement showed no adverse changes over four years in a chronic sample (Austin et al., 1999). The present study examined the effects of persistent seizures over time on specific neuropsychological functions that are commonly affected in children with epilepsy. It was predicted that neuropsychological performance would decline but only in those children with incomplete seizure control. The sample consisted of 173 children with chronic epilepsy (ages 8-15 years; 49% female, 91% White/Non-Hispanic; 79% one seizure type, 79% on one medication, 69% with active seizures). Children diagnosed with mental retardation were excluded. There were 164 children at baseline and 130 children at 24 months later who completed a comprehensive neuropsychological battery assessing 9 cognitive domains and academic achievement in reading, writing, and math. For seizure control, participants were classified at baseline and at 24 months as active (seizure within past 12 months) or controlled (no seizures in 12 months). A repeated-measures analysis of covariance, which controlled for age, age at onset, and gender, was used to test the main effects and the interactions of Time and Seizure Control for the neuropsychological functions. There was a Time x Seizure Control interaction (decline over time but only for children with active seizures) for two of the nine neuropsychological domains: executive processing [Category Test, [italic]F[/italic](1, 123)=5.07, [italic]p[/italic]=0.03] and rapid automatic naming [Stroop Word Trial, [italic]F[/italic](1, 123)=4.76, [italic]p[/italic]=0.03]. A main effect for seizure control (active worse than controlled) was observed for two other domains: receptive language [Tokens Test, [italic]F[/italic](1,32)=8.74, [italic]p[/italic]=0.006] and verbal memory [WRAML Story Memory, [italic]F[/italic](1,32)=4.39, [italic]p[/italic]=0.04]. No other main effects or interactions were observed, [italic]p[/italic][gt].05. Consistent with research on IQ, uncontrolled seizures were associated with lower performance in two neuropsychological domains at baseline and were associated with declines (or less improvement) in two other domains. Also consistent with prior research, academic achievement was stable over the time period of this study. (Supported by PHS R01 NR04536 from NIH/NINR to J.K.A.)