Epilepsia, epileptiform abnormalities, non-right-handedness, hypotonia and severe decreased IQ are associated with language impairment in autism.

The aim of this study was to categorize speech problems in autistic children in a manner allowing recognition of associated risk factors. We were specifically interested in the role of epilepsy and epileptiform activity in EEG in autistic patients since these dynamic processes can influence each other. We combined subtypes of autism with degrees of their functionality and we selected three speech endpoints: i) delayed development of speech, ii) complete mutism and iii) regression of speech. We retrospectively examined 205 autistic children (boys 145/70.7%, mean age 10 years). Median IQ was 55 (15;104) and median Childhood Autism Rating Scale (CARS) ranged within 38 (32;48). Univariate and multivariate logistic regression helped to define clinical and diagnostic factors that were significantly associated with speech endpoints. Epileptic seizures, epileptiform EEG abnormalities, non-right-handedness, hypotonia and severe decreased IQ score were found to be the most important mutually independent factors contributing to the increased risk of speech-related problems in patients with ASD.