Rethinking Autism: Detection and Treatment At 1 Year?
Rethinking Autism: Detection and Treatment At 1 Year?
Assistant Professor, Department of Neurosciences; Assistant Director, Autism Center of Excellence, University of California, San Diego
First published in Psychiatry Weekly, Volume 6, Issue 15, July 25, 2011
This interview was conducted on May 19, 2011 by Lonnie Stoltzfoos
When autism was first described by Leo Kanner in 1943, the outcome for affected children was bleak, often leading to institutionalization. Today, however, following decades of clinical study and improved treatments, children with an autism spectrum disorder (ASD) generally live at home and attend public schools with non-ASD children; many finish high school and go on to find jobs in their community.
One reason for this positive change may be the steady increase in early detection and treatment, and the resulting positive impact on the developing brain. Some experts, however, such as Dr. Karen Pierce, believe that many children are not being identified and treated early enough. The most recent report from the Centers for Disease Control notes that the mean age of ASD diagnosis in the US occurs around 4 years of age. Yet most parents sense that something is going wrong with their child’s development years earlier.
1-Year ASD Screening
Dr. Pierce, a neuroscientist who has spent several decades in the autism field, recently published the results of a trial in which infants ~1 year old were screened for potential developmental delays. Dr. Pierce developed a program called “The 1-Year Well-Baby Check-Up Approach,”1 which is centered upon a brief parent-report scale to screen for communication delays (“Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler”). The scale measures a wide range of domains, such as a baby’s interest in showing objects to other people, but is not autism specific. Believing that communication delays could be predictive of autism spectrum disorders, Dr. Pierce persuaded 137 pediatricians in the San Diego area to administer the parent-report tool during infants’ 1-year exams. Any infant that failed the screening tool could be referred to the UC San Diego Autism Center of Excellence for in-depth cognitive, language, and social testing. Infants were also eligible to receive a free MRI scan and blood samples for future genetics studies.
“If the results of a child’s social development screening were below expectations at 12 months, we would refer them to treatment,” says Dr. Pierce. “We did not assign a label at 12 months. We informed the parent that their child was not meeting some expected milestones, and then conducted subsequent follow-ups every 6 months using the same battery of tests each time. Eventually it becomes obvious who has an ASD and who does not, at which point we can begin early intervention for any children with a confirmed ASD diagnosis. In our program, all toddlers showing developmental delays got into treatment between 16 and 19 months, which is very young, considering that the mean age of diagnosis for autism is currently between 3 and 4 years of age, and most children don’t start treatment until that age.”
One objective of Dr. Pierce and colleagues’ recent study was to ascertain the predictive value of the CSBS-DP IT screener for ASDs. Out of ~10,000 infants screened at 12 months, 184 did not meet developmental thresholds and were referred to additional testing. Of that group, 32 eventually received an ASD diagnosis.
“Since the current epidemiological rates for ASDs are 65 out of every 10,000, one might expect that our efforts would detect twice as many eventual ASD diagnoses than we actually did,” says Dr. Pierce. “It makes sense, however, that we did not detect as many as 65 cases because of varying onset patterns. A 12-month screening tool obviously will not detect cases of a late onset, or a regressive onset pattern, where children suddenly lose skill around 2 or 3 years of age. Also, Asperger’s disorder, which is usually not detected until elementary school, is included in the 65 per 10,000 prevalence figure, and it’s unrealistic to think that a 5-minute screening tool will catch those cases so early in life. The upside, of course, is how such a simple and short screening tool can actually be this effective.”
The Value of Early Intervention
Nearly 25% of the children who went on for additional testing after the 1-year evaluation turned out to be completely normal. The estimated positive predictive value of the screening tool is therefore 75%. Parents of 1 in 4 children are eventually greatly relieved, of course, and Dr. Pierce notes that their initial anxiety and tension cannot be completely ignored.
“From the real world clinical perspective, physicians know they are handing out a screening tool with a 25% false-positive rate,” says Dr. Pierce. “But I believe that several hours of additional testing for 1 out of those 4 families does not outweigh the benefit of helping those other 3 children through early detection and intervention. From a scientific perspective, many parents of the ‘false-positive children’ keep them enrolled in our study as controls, so those false-positives are incredibly valuable for our quest to identify early ASD biomarkers.”
An array of research shows that early intervention can redirect the trajectory of ASDs. Detecting ASDs in children as young as 12 months is a brand-new concept, however, and so far only Dawson and colleagues2 have published a study on early intervention in children as young as 18–30 months. In their 2009 study, children in the experimental treatment group (The Early Start Denver Model) gained an average of 18 IQ points, compared with 10 IQ points in children receiving treatment-as-usual.
“It was recently discovered that limited neurogenesis can occur in adulthood, but for the most part humans are born with all the brain cells they will ever have,” concludes Dr. Pierce. “Synaptic connections, especially in the frontal lobe, occur in earnest between 1 and 3 years of age. So if we can identify developmental problems early, and intervene while the connections are still forming, it stands to reason that we can provide positive guidance and treatment to impact and sculpt brain development, thereby improving outcomes for affected children.”
Disclosure: Dr. Pierce has received research funding from the NIMH R01 and P50 Center Grant.
1. Pierce K, Carter C, Weinfeld M, et al. Detecting, Studying, and Treating Autism Early: The One-Year Well-Baby Check-Up Approach. J Pediatr. 2011 Apr 19. [Epub ahead of print]
2. Dawson G, Rogers S, Munson J, et al. Randomized, controlled trial of an intervention for toddlers with autism: the Early Start Denver Model. Pediatrics. 2010;125:e17-23. Epub 2009 Nov 30.