Some children who are accurately diagnosed in early childhood with autism lose the symptoms and the diagnosis as they grow older, a study supported by the National Institutes of Health has confirmed. The research team made the finding by carefully documenting a prior diagnosis of autism in a small group of school-age children and young adults with no current symptoms of the disorder.
The report is the first of a series that will probe more deeply into the nature of the change in these children's status. Having been diagnosed at one time with an autism spectrum disorder (ASD), these young people now appear to be on par with typically developing peers. The study team is continuing to analyze data on changes in brain function in these children and whether they have subtle residual social deficits. The team is also reviewing records on the types of interventions the children received, and to what extent they may have played a role in the transition.
"Although the diagnosis of autism is not usually lost over time, the findings suggest that there is a very wide range of possible outcomes," said NIMH Director Thomas R. Insel, M.D. "For an individual child, the outcome may be knowable only with time and after some years of intervention. Subsequent reports from this study should tell us more about the nature of autism and the role of therapy and other factors in the long term outcome for these children."
The study, led by Deborah Fein, Ph.D., at the University of Connecticut, Storrs, recruited 34 optimal outcome children, who had received a diagnosis of autism in early life and were now reportedly functioning no differently than their mainstream peers. For comparison, the 34 children were matched by age, sex, and nonverbal IQ with 44 children with high-functioning autism, and 34 typically developing peers. Participants ranged in age from 8 to 21 years old.
Prior studies had examined the possibility of a loss of diagnosis, but questions remained regarding the accuracy of the initial diagnosis, and whether children who ultimately appeared similar to their mainstream peers initially had a relatively mild form of autism. In this study, early diagnostic reports by clinicians with expertise in autism diagnosis were reviewed by the investigators. As a second step to ensure accuracy, a diagnostic expert, without knowledge of the child's current status, reviewed reports in which the earlier diagnosis had been deleted. The results suggested that children in the optimal outcome group had milder social deficits than the high functioning autism group in early childhood, but had other symptoms, related to communication and repetitive behavior, that were as severe as in the latter group.