Abstracts

Rationale: The neurobehavioral comorbidities of pediatric epilepsy (psychopathology, impaired cognition, linguistic deficits, and abnormal brain volumes) are inconsistently related to seizure variables. Since psychiatric disorders, intelligence, language, social communication, and brain structure are heritable, it is important to determine if the comorbidities of these children reflect familial effects. From the psychosocial perspective, however, having a sibling with epilepsy could also contribute to psychiatric and poor academic achievement in the sibling without epilepsy. We, therefore, compared psychopathology, IQ, language, social communication, and fronto-temporal volumes in the siblings of children with epilepsy (Epi-S) to those of their epilepsy probands (Epi-P) and to healthy control subjects (Ctl-P) and their siblings (Ctl-S). Within the Epi-S group, we also examined the association of Epi-P illness variables with Epi-S psychopathology and academic achievement. Methods: The study included 288 children (49 Epi-S, 85 Epi-P, 61 Ctl-P, 33 Ctl-S) with 46 Epi-S/P and 30 Ctl-S/P pairs, aged 6-17 years. Structured psychiatric interviews, IQ, language, social communication, and academic achievement testing were administered to all subjects. Parent and child self-report questionnaires provided information on behavior problems, depression, and anxiety. Children underwent MRI scans at 1.5 T. Tissue was segmented and total brain, frontal lobe, frontal parcellations and temporal lobe volumes were computed. Parents and medical charts provided epilepsy-related information. Mixed models controlling for age, gender, socioeconomic status and ethnicity were estimated on psychopathology, IQ, language, social communication, and volume measures in the study groups, using family as a random effect. Posthoc analyses compared Epi-S with Ctl-P and Epi-P groups. Within Epi-S, regressions were used to see if psychopathology and academic achievement were associated with proband seizure frequency and age of onset. Results: The Epi-S and Ctl-P groups did not differ significantly on most of the measures except number of children with mean Full Scale (20% vs. 7%, p<.04) scores one standard deviation below average, parent report of more school problems (t(67)=2.75, p<.008), and trend for higher psychiatric diagnosis rate (31% vs. 14%, p <.06). The Epi-S differed significantly from Epi-P on all measures except psychiatric diagnosis rate (31% vs. 44%, p>.2). Epi-P older age of epilepsy onset was related to Epi-S psychopathology (X2(1)=4.0, p<.05) and poor academic achievement (t(42)=2.7-2.3, p<.01-.03). Conclusions: The increased rate of cognitive deficits, school problems, and psychiatric diagnoses in Epi-S imply a familial effect not found for language and brain volumes. However, our findings underscore the need to also examine potential psychosocial effects, such as how later onset of epilepsy affects the emotional well-being and school performance of siblings of children with epilepsy.