Autism spectrum disorder (ASD) is a family of neurodevelopmental disorders made up of autism, Asperger’s syndrome, and pervasive developmental disorder not otherwise specified. While the pathophysiology behind these disorders remains largely unknown, each shares a specific constellation of symptoms including impaired communication, diminished social skills, and unusual behaviors or interests.
The number of children with ASD is on the rise. In four years, the prevalence has gone from 6 to 9.4 cases per 1,000 individuals (Schieve LA et al, Matern Child Health J 2012; S151-157). To be fair, part of this is a function of changed definitions and looking at the entire autism spectrum rather than just autism itself. Using the new criteria, we have approximately 673,000 people in the United States suffering with these disorders (Kogan MD et al, Pediatrics 2009;124(5):1395-1403).
The impact of ASD is significant, requiring considerable financial resources and time to ensure maximum rehabilitation. In spite of all that we’re doing now, more than half of those suffering with ASD go on to have poor or very poor outcomes as adults (Howlin P, J Child Psychol Psychiatry 2004;45(2):212- 229). This leads us to ask what we can do better. As physicians, we may (or may not) find medication recommendations easy to make, but many of us feel inadequate in our ability to meet the nonpharmacologic demands of ASD.
Effectively Screening for ASD
Like many illnesses, treatment starts with early screening, which ideally begins at home through parental observation. As we advocate for our patients, we can increase parents’ awareness of the signs and symptoms of ASD and point them toward resources such as the Autism Speaks website, which provides an online screening tool parents may find helpful (http://bit.ly/PZopBV). The CDC recommends primary care physicians formally screen children for ASD at 18- and 24-month checkups. However, research shows that 62% of clinicians don’t screen because they don’t understand the screening tools (Dosreis S et al, J Dev Behav Pediatr 2006;27(2 Suppl):S88-94).
To help combat this, the CDC website provides sample screening exams and links to both public and proprietary diagnostic tools with tips not only on how to complete these, but also how to work them into scheduled exam times (http://1.usa.gov/aeO0nX). There is also a fairly comprehensive list of screening tools for children up to age six available from the American Academy of Pediatrics at http://bit.ly/12afM9N.
However, few child psychiatrists see children early enough to take advantage of these instruments. Instead, we get the difficult cases that have not been diagnosed previously or have not presented clinically until latency age or beyond. For these, the best bets are the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Scale (ADOS), both of which have sensitivity and specificity in the 75%-80% range or higher when used together (Rotatori AF et al. Autism and Developmental Disabilities: Current Practices and Issues (Advances in Special Education). Bingley, UK: JAI Press;2008).
The ADOS and ADI-R are neither fast nor simple to learn, and require specialized training that presents a significant barrier for most practitioners. The ADOS requires a two day training workshop or video training (www.wpspublish.com) followed by enough practice evaluations to reach competency, generally at least eight. The ADI-R involves an 18 hour video-based training available through WPS (www.wpspublish.com), as well as inperson trainings sponsored by various educational and research organizations. However, once learned, they allow the provider to diagnose with confidence.
On the other hand, the DSM criteria are also fairly good for diagnosis and are both fast and easy to learn. There has been found to be good agreement between the ADOS and clinical judgment (Rotatori op cit).