Some children with an accurate diagnosis of an autism spectrum disorder (ASD) may eventually “outgrow” the diagnosis and have normal levels of overall functioning that are within normal testing limits, new research suggests.
The study compared 34 school-age children and young adults with a prior diagnosis of ASD who had achieved “optimal outcome” (no current symptoms of the disorder) with 44 matched individuals with high-functioning autism (HFA) and 34 typically developing peers.
Results showed that the first and third groups did not differ significantly on mean test scores of communication, social interaction, face recognition, and most language subscales.
Although the optimal outcome group had milder symptoms of social dysfunction than the HFA group during their early developmental years, difficulties with communication and repetitive behaviors were equally severe.
Dr. Deborah Fein
“I wasn’t too surprised by the overall findings, but it was surprising just how indistinguishable from typically developing most of these kids were on virtually every measure,” lead author Deborah Fein, PhD, professor in the Department of Psychology and the Department of Pediatrics at the University of Connecticut in Storrs, toldMedscape Medical News.
She noted that the investigators are now reviewing records of the various types of interventions the children received and what (if any) role they might have played.
“The findings suggest that there is a very wide range of possible outcomes,” said Thomas R. Insel, MD, director of the National Institute of Mental Health, in a release.
“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 was published online January 16 in the Journal of Child Psychology and Psychiatry.
According to the investigators, ASDs “are generally considered lifelong disabilities.”
“Prior studies have 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,” they note.
“For many years, in clinical practice, we’ve seen kids who move off the autism spectrum. Most clinicians I have spoken with have had similar experiences, but it hasn’t really been documented in a way that was convincing to a lot of people,” said Dr. Fein.
“In most cases, it is a lifelong disability. So what we set out to do was to collect a sample of children who we could really document in a pretty rigorous way.”
The investigators recruited 34 children and young adults (between the ages of 8 and 21 years) who had previously received a documented diagnosis of ASD but were now functioning at optimal outcome.
This group (mean age, 12.8 years) was then matched by age, sex, and nonverbal IQ with 44 individuals with HFA (mean age, 13.9 years) and 34 who were considered “typically developing” (mean age, 13.9 years).
Current status of all participants was evaluated using standard cognitive and observational tests and parental questionnaires.
Verbal and nonverbal IQs were measured using the Wechsler Abbreviated Scale of Intelligence, and communication, daily living, and socialization were measured using the Vineland Adaptive Behavior Scales. Other tests included the Social Communication Questionnaire, Benton Facial Recognition Test, and Clinical Evaluation of Language Fundamentals (CELF), 4th edition.
IQ a Factor?
Results showed that scores were not significantly different between the optimal outcome group and the typically developing group on current tests of socialization, communication, facial recognition, and most of the CELF subtests.
Although “formulated sentences” and core CELF composite scores differed significantly, the researchers note that this is probably due to very high scores from the typically developing group. The optimal outcome group still scored above average on these 2 tests.
Both the optimal outcome and typically developing groups also had mean verbal IQ scores that were 7 points higher than the score for the HFA group.
“Additional study may reveal whether IQ may have been a factor in the transition” to optimal outcome, report the investigators in a release.
“Although possible deficits in more subtle aspects of social interaction or cognition are not ruled out, the results…demonstrate an overall level of functioning within normal limits for this group,” they write.
However, they add that the study cannot explain which children diagnosed with ASD might someday lose their symptoms.
No Predictors of Optimal Outcome
“All children with ASD are capable of making progress with intensive therapy, but with our current state of knowledge, most do not achieve the kind of optimal outcome that we are studying,” said Dr. Fein in a release.
Still, she told Medscape Medical News that her best guess, based on literature and her own clinical experience, is that between 10% and 25% of children lose their ASD diagnosis.
“But there really is nothing that’s clearly distinguishing these kids when they’re very young. You can’t do an evaluation on a child when they’re 2 or 3 and predict what will happen. So that’s a reason for providing the best intervention for everybody,” said Dr. Fein.
“It can’t hurt. Some will reach optimal outcome, while others will make considerable progress,” she said.
The investigators have announced that this is the first in a series of studies that will continue assessing these participants. Structural and functional brain imaging data and psychiatric outcomes have already been collected, and results will be shared in subsequent articles.
“Our hope is that further research will help us better understand the mechanisms of change so that each child can have the best possible life,” said Dr. Fein.
The study was funded by a grant from the National Institutes of Health. The study authors have disclosed no relevant financial relationships.
J Child Psychol Psychiatry. Published online January 16, 2013.
Source: With permission from Medscape. Article by D. Brauser