Prevalence of Unrecognized Autism Spectrum Disorders in Epilepsy: A Clinic-Based Study.

Objective: To assess prevalence of unrecognized autism spectrum disorders (ASDs) in children with epilepsy using Diagnostic and Statistical Manual IV (DSM-IV) criteria and to evaluate factors affecting it in this population. It was a cross-sectional study conducted at a teaching hospital. It included randomly selected 106 children in the age 4-12 years with epilepsy, and without any structural anomaly identifiable on computed tomography/magnetic resonance imaging. Children already diagnosed with ASD were excluded.

Materials and Methods: Detailed clinical evaluation was carried out. Intelligence quotient (IQ) was assessed using Development Profile-II for all and Binet and Kulshrestha test, wherever possible. Participants were screened using Social Communication Questionnaire (SCQ). Those with SCQ score of ≥15 were evaluated for ASD using DSM-IV criteria. Childhood Autism Rating Scale was administered to assess the severity of autism. Data were analyzed with univariate and logistic regression analyses.

Results: A total of nine children were screened positive, of them, eight were diagnosed with ASD using DSM-IV criteria. The prevalence of unrecognized ASD was 7.5/100. On univariate analysis, intellectual disability ( P < 0.01) and young age of onset of epilepsy ( P = 0.03) were significantly associated with ASD. On multivariable analysis, only intellectual disability was significantly associated with ASD ( P < 0.01). There was no significant association with gender, seizure type, frequency of seizures, intractability of epilepsy, or the number of antiepileptic drugs used.

Conclusion: ASDs are more prevalent in children with epilepsy than in general population. In cases with associated intellectual disability, co-occurrence of ASD is further increased. All children with epilepsy, particularly those with IQ ≤ 50, irrespective of age of onset of epilepsy, seizure type, frequency of seizures, or intractability of epilepsy, should be screened for ASD.