Abstracts

Rationale: This study examined the relationship between severe psychopathology and cortical brain volumes in pediatric epilepsy by comparing fronto-termporal brain volumes in patients with multiple and no psychiatric diagnosis to healthy children. It also determined the role played by seizure control, attention deficit hyperactivity disorder (ADHD), and family history of psychopathology in this association.Methods: Structured psychiatric interviews identified 35 epilepsy subjects without DSM-IV diagnoses, 18 with multiple DSM-IV diagnoses and 36 control subjects with no psychiatric diagnosis. These subject groups were comparable on demographic variables. Parents provided information on seizure control and family history of psychopathology (1st and 2nd generation). Tissue from 1.5T MRI scans on all subjects was segmented and volumes of total brain, frontal lobe and frontal parcellations were computed. ANOVAs were estimated to examine volume differences between groups, controlling for age. For those volumes with significant group differences, additional measures such as family history of psychopathology, presence of ADHD, and seizure control were examined to determine if these were significant predictors of the group differences. Results: ANOVAs of brain volumes with age as covariate demonstrated a main effect for total, dorsolateral prefrontal (DLPFC), and orbital frontal (OBF) gray matter (GM) volumes with significantly smaller total (p < .02), DLPFC (p < .006), and OBF GM volumes (p < .008) in the multiple diagnoses vs. the control group. There was a trend for smaller total and DLPFC GM volumes in the multiple compared to the no diagnosis epilepsy subgroup and no significant volumes differences between the patients without a diagnosis and the controls. Controlling for family history of psychopathology did not change these findings. Of the 18 subjects with multiple DSM-IV diagnoses, 11 had ADHD and 12 had uncontrolled seizures. The presence of ADHD was not a significant predictor of volume differences in these subjects. However, subjects with uncontrolled seizures had significantly smaller DLPFC (p < .03) but not OBF GM volumes. Conclusions: This is the first study to demonstrate that severe psychopathology in children with epilepsy with average intelligence is associated with reduced DLPFC GM volumes and that this finding reflects uncontrolled seizures rather than an ADHD diagnosis or family history of psychopathology.