Abstracts

Rationale: The incidence of epilepsy is higher in children with autism (4-32% vs 0.5%). Reports of the association between autism and epilepsy from older literature reported onset around puberty, an increased incidence in girls, and a tendency to medical refractoriness. In current clinical practice, this no longer appears to be the case. Several recent studies have identified a higher incidence of epilepsy in younger children and in boys with autism. The increased diagnosis of autism in young children may identify a different population than was previously diagnosed, and features of epilepsy may also differ. An observational study was conducted to characterize clinical features of seizures and, anticonvulsant drug usage in children with diagnoses of autism and epilepsy. Methods: We conducted a retrospective review of medical records of children, ages 2-17 with autism and epilepsy (excluding severe confounding comorbidities), evaluated in a single Pediatric Neurology Clinic, from April 2004-June 2007 and with follow-up longer than 1 year. Children with epilepsy, without autism served as controls. Results: Sixty-seven children with Autism and Epilepsy (AE) were identified [51 male, mean age of cohort=10.5 years]. Average age of seizure onset was 3.8 years. Generalized seizures were identified in 48 subjects, focal seizures in 42. 11 subjects had seizures daily, 8 had one or more/week, 4 had one or more/month, 22 had one or more/year, and 22 had none in the last year. 64 controls (E) were identified [38 male, mean age 10.05 years], with an average age of seizure onset of 4.7 years. Generalized seizures occurred in 41, focal seizures in 32. 5 had daily seizures, 4 had one or more/week, 8 had one or more/month, 24 had one or more/year, and 23 had none in the last year. Average number of anticonvulsants prescribed from seizure onset to the most recent visit was 4.0 (SD=2.8). The average number of anticonvulsants at the most recent visit was 1.5 (SD=1.1). In the control group, the average number of anticonvulsants prescribed from seizure onset to most recent seizure visit was 3.75 (SD= 2.54) and the number of anticonvulsants at the most recent visit was 1.6 (SD=0.96). Prescribed anticonvulsants were changed 121 times in the AE group , and 87 times in the E group (Chi-sq df=1, p= 0.02). 59 subjects had abnormal EEGs and 24 had abnormal neuroimaging studies in the AE group, compared with 60 abnormal EEGs and 22 abnormal neuroimaging studies in the E group. The spectrum of EEG and imaging abnormalities were similar in both groups. Conclusions: Our cohort shows a larger number of cases with autism and epilepsy (3:1) are male, with an earlier seizure onset. Children with Autism and Epilepsy have similar epilepsy syndromes and seizure types as compared with children with Epilepsy alone. EEG and neuroimaging are not particularly different in either group. Medications were more likely to be changed in children with autism and epilepsy. While Autism is a comorbidity with Childhood Epilepsy, dual diagnoses does not confer extra morbidity with respect to intractability of epilepsy.