Abstracts

Prediction of cognitive function has been difficult in children with epilepsy, since cognitive dysfunction in epilepsy involves multiple causes. We determined whether occipital alpha peak frequency during quiet wakefulness can independently predict cognitive function in children with focal epilepsy. A total of 33 children (age: 6 - 17 years; 20 boys) with focal epilepsy were included in the study. None of the subjects had visual, hearing, or motor deficits. Children with idiopathic childhood epilepsy with occipital paroxysms or central-temporal spikes were also excluded. Occipital alpha peak frequency during quiet wakefulness with eye closure and interictal spike frequency during wakefulness were quantitatively measured by scalp EEG. Interictal spike frequency was categorized into four groups (0, 0-1, 1-10, and [gt]10 per minute; Asano et al, 2004). A hierarchical multiple regression analysis was performed to determine whether age-adjusted occipital alpha peak frequency can predict the full-scale IQ independently from spike frequency category and the number of antiepileptic medications taken by the patient. An analysis of the zero-order correlations revealed that each of the three predictors (age-adjusted occipital alpha peak frequency, spike frequency category and the number of anti-epileptic medications) is about equally correlated to full-scale IQ and each of these predictors accounted for 20% - 23% of the variance ([italic]p[/italic] [lt] 0.01 for all three predictors). In a hierarchical multiple regression analysis, the categorical measure of spike frequency and the number of medications used were entered in the first step and accounted for 31% of the variance in the IQ measure ([italic]F[/italic](2, 30) = 6.77, [italic]p[/italic] = 0.004). In a second step of the analysis the age-adjusted occipital alpha peak frequency was entered and accounted for an additional 13% of the variance ([italic]F[/italic](1, 29) = 6.49, [italic]p[/italic] = 0.016). Occipital alpha peak frequency during quiet wakefulness is an important factor independently predicting the full-scale IQ in children with focal epilepsy even after controlling for both interictal spike frequency and the number of anti-epileptic medications. Quantitative measurement of occipital alpha peak frequency and interictal spike frequency data extracted from a single video-EEG session combined with the number of antiepileptic drugs may provide important information for prognosis of overall cognitive function in children with focal epilepsy. (Supported by NIH: K23NS047550.)