5|25: Celebrating Five Years of Autism Science Day 17: Recovery from Autism Spectrum Disorders
In honor of the anniversary of Autism Speaks’ founding on Feb 25, for the next 25 days we will be sharing stories about the many significant scientific advances that have occurred during our first five years together. Our 17th item, Recovery from Autism Spectrum Disorders, is from Autism Speaks’ Top 10 Autism Research Events of 2008.
For decades, autism spectrum disorders have been assumed to be life-long conditions. Recently, evidence has begun to emerge suggesting that a significant minority of children with well-documented autism spectrum disorder (ASD) can recover; in 2008 the first research publication to define and review recovery was released, placing the percentage of children who recover in the range of 3-25%.
In December 2008, a team of researchers from the University of Connecticut and their colleagues published an inspiring and provocative article documenting cases of recovery in autism. Recovery was defined as previously having had clearly defined ASD but currently no longer meeting criteria for any ASD. Furthermore, the recovered individual is now learning and using skills with a “quality that reaches the trajectory of typical development in most or all areas.” Using these criteria, the research team documented and followed a group of children, now between 8-18 years of age, with a history of ASD who are now “recovered.” The authors point out that children who recover from autism may nevertheless be at risk for other challenges, such as subtle difficulties with some aspects of language, anxiety, or learning disabilities.
In a previous study, the same researchers reported several cases of ASD that evolved into ADHD with no autism. Interestingly, most of these children had evidence of early regression and recurrent ear infections. Most had also received early intensive behavioral intervention. Recent outcome studies have shown that core symptoms of autism tend to improve by adulthood, especially difficulties in the areas of communication. Several outcome studies have found that about 10-20 percent of adults previously diagnosed with ASD no longer meet criteria for the condition.
How can recovery occur? One clear possibility is that successful treatment moved children who had ASD off of the spectrum. However, as the researchers point out, since most children who receive even the best and most intensive intervention do not recover, treatment alone cannot be the explanation. Both treatment and inherent characteristics of the child are likely to explain recovery. The research team therefore looked for child characteristics that predict optimal outcome, identifying higher IQ, receptive language ability, verbal and motor imitation, motor development, and an early age at diagnosis and initiation of treatment as promising predictors. In the majority of studies that report recovery, behavior intervention was used alone or in combination with other therapies.
The authors point out that although early intervention is associated with optimal outcome, this fact should not be used as an argument against the need for intervention in older children in light of the growing evidence of brain plasticity throughout the life span. Finally, this thoughtful article considers a wide range of biological mechanisms that may help explain the process of recovery. Future research directions will now provide us with insights into ways of improving the outcomes – and the chances for recovery – for all individuals with ASD.
Update since this story was first run: In 2009 researchers reported in the journal Pediatrics that they had used the National Survey for Children’s Health, a voluntary, parent-reported survey, to examine ASD prevalence in the US. Among other surprising results, they discovered that a substantial portion of parents reported their children had previously been diagnosed with an ASD but did not currently have the condition.