Cognitive, adaptive, and behavioral differences between young children with autism spectrum disorders with and without regression of language skills

The charts of 51 children with autism spectrum disorders were reviewed for this archival study. The children are participants in a longitudinal study on autism, genes, and the environment being conducted at The University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School. Data from a neurobehavioral assessment that was conducted when the participants were between the ages of 24 and 42 months were analyzed for differences between the children with and without a history of language regression, as ascertained during a medical history. In order to test the hypotheses that children with a history of language regression would show lower cognitive and adaptive functioning and more autistic symptoms, a Multivariate Analysis of Variance was conducted on scores from the Differential Ability Scales, Vineland Adaptive Behavior Scales, and the Autism Diagnostic Observation Schedule. No significant differences were found between the groups in cognitive and adaptive functioning or in autistic symptomatology. The overall findings of this study do not support the theory that autism with regression is a subset of the disorder with a different etiology than autism without regression and are commensurate with the findings of recent studies of similar age children which view autism spectrum disorder with regression as a variation in the development of this disorder. Differences in autism severity and the nature of regression may have contributed to these findings. Future research should focus on methods to divide groups more homogeneously and to take into account variations in development and nature of regression in order to detect if real differences exist between children with and without language regression. In addition, longitudinal follow up will be important to see if differences emerge with maturation. By evaluating variations in the development of children with autism spectrum disorders, treatment outcomes for subgroups can be studied with better precision. In practice, regression may serve as one marker for early identification of autism spectrum disorders.