Abstracts

RATIONALE: The prevalence, severity, and neurological predictors of ADHD symptoms in children with epilepsy have not yet been well delineated, nor has the association between frontal-lobe epileptiform activity and inattention/disinhibition been verified empirically. METHODS: Using the ADHD Rating Scale-IV, we assessed the prevalence and severity of behaviors symptomatic of ADHD in 67 children with epilepsy from a large tertiary care hospital. Data on the type and location of EEG abnormalities, as well as etiology, number of current and previous antiepileptic medications, seizure frequency and IQ scores were also evaluated as predictors of ADHD-IV scores. RESULTS: Attention disorders, as measured by the Attention Scale of the ADHD-IV, were common in this population, with 50% of children rated as having severe attentional difficulties (>2SD above the normative mean). In contrast, only approximately 20% of children with epilepsy were rated as having clinically significant impulsivity/hyperactivity problems. Children with epileptiform EEG abnormalities originating in the the frontal lobe were more likely to be rated as having attentional problems than those with non-frontal EEG abnormalities. No differences between groups were found for impulsivity/hyperactivity. In terms of other predictive factors, ADHD behaviors were correlated with number of current antiepileptic medications, but not to other neurological variables such as seizure frequency or to general intellectual ability. CONCLUSIONS: The results suggest that children with frontal lobe epileptiform abnormalities may be more likely to present with attentional problems than are other children with epilepsy, and that neurological factors such as antiepileptic medication are important predictors of ADHD symptoms in pediatric epilepsy. The results also suggest that many children with severe epilepsy fulfill criteria for the Primarily Inattentive ADHD subtype instead of the more commonly diagnosed Combined (Inattention/Hyperactivity) ADHD subtype.