Abstracts

Rationale: Attention Deficit Hyperactivity Disorder (ADHD) is a common comorbid condition in childhood epilepsy. Little is known regarding the nature, frequency and timing of either the associated neurobehavioral and cognitive complications or the underlying etiology of ADHD in epilepsy. This investigation examined: 1) the rate of ADHD and its subtypes, 2) the association of ADHD with abnormalities in academic, neuropsychological, behavioral, and psychiatric status, and 3) the etiology of ADHD in pediatric epilepsy. Methods: 75 children (age 8-18 years) with new onset (diagnosis in the past 12 months) idiopathic epilepsy and 62 healthy controls underwent a structured interview (K-SADS) to identify DSM-IV defined ADHD, and each child participated in a neuropsychological evaluation. For each child, parents characterized executive function, detailed academic and educational progress, and reported risk factors during gestation and delivery. MR volumetrics were obtained for children with epilepsy and healthy controls. Results: The results indicate that ADHD is significantly more prevalent in children with new onset epilepsy compared to healthy controls (30% vs. 6%, p < .001) and is characterized predominantly as the inattentive type of ADHD (52%). Onset of ADHD antedates the diagnosis of epilepsy in the majority of children (82%). ADHD in childhood epilepsy is associated with significantly increased rates of school based remedial services, academic underachievement, prominent deficits in executive function, and a wide range of parent-reported dysexecutive behaviors. ADHD in pediatric epilepsy is not associated with demographic or clinical epilepsy characteristics nor a wide range of potential risk factors during gestation and birth. Quantitative MRI demonstrates that ADHD in epilepsy is associated with significantly increased gray matter in distributed regions of the frontal lobe (p=.034) and significantly smaller brainstem volume (p=.006). Conclusions: ADHD is a significant comorbidity of new onset idiopathic epilepsy associated with a diversity of salient educational, cognitive, and behavioral complications that antedate epilepsy onset in a significant proportion of cases, and it appears to be related to neurodevelopmental abnormalities in brain structure (Source of funding: NINDS RO1-44351).