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Wednesday, April 2, 2014

Chasing the Wind: Determining the Prevalence of Autism

Last month, the CDC reported that they expect Autism (ASD) prevalence to drop up to 20% in 2014. However, this week, the CDC reports that the estimated prevalence has increased by 30%.

Autism is a syndrome with multiple causal factors.
Children should probably be diagnosed according to
causal factors, instead of lumped together
under one behavioral-based label.
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Why the increase in cases? Why the apparently mixed reports? Determining the prevalence and incidence of any illness is difficult, especially with ASD. The increase in cases is because the numbers of children with average or above average intelligence who are being diagnosed as Autistic has increased. As of now, 50% of children diagnosed with Autism have average or above-average intelligence. Before the DSM V, children who were white and wealthier were more likely to be diagnosed with Asperger's disorder, while children who were poor and minority were more likely to be diagnosed with PDD NOS and Autism.

The inappropriate use of the diagnosis 
of ASD continues. This is because the criteria for ASD 
are broad, vague, and subjective (non-scientific).

There are no reliable bio-markers for ASD (PDD NOS, Asperger's, Autism) that will reliably predict or determine if a child has ASD. So, the diagnosis is made by observations of behaviors. One mental health provider may affirm the diagnosis of the other, but that does not confirm that the child has ASD. If the criteria were more specific and narrow, there would be less agreement, and mental health providers may be more cautious about who is diagnosed with ASD. Furthermore, if the diagnostic criteria were based on another dimension, such as causal factors, then that might be a better guide for treatment. For example, labeling children with Fragile X syndrome as ASD lumps them with children who have a different causal elements. Currently, tens of thousands of ASD cases are children with Fragile X syndrome.

When the CDC reported that the prevalence of Autism would decline, I was skeptical. Given the new criteria in the DSM V, I suspect that many more children will be included in the ASD category to point of it becoming meaningless (a diagnosis of exclusion). Given the diagnostic biases based on race, class, and gender, it was never reliable. The changes to these diagnosis in the DSM V will make it a useless diagnosis.

It becomes nearly impossible to study outcomes for children diagnosed with ASD, because there are so many different types of children who will be placed in that category. It will also become impossible to predict what treatments will work for one child with ASD compared to another, for the same reason. Since the changes in the diagnostic categories in May of 2013, all the research on Autism, Asperger's and PDD NOS will no longer be useful.

We expect revisions to diagnostic criteria to be an improvement, but, with regards to ASD, it's a move to an even less scientific category of mental illness than in the DSM IV-TR. The benefit of the convenience of having one diagnosis for such a wide-variety of behaviors is far out-weighed by disadvantage of specificity. The DSM would of been better-off developing more categories, not less.

The DSM V seems to minimize the language deficits over the social deficits. It also seems to lack an emphasis on severity of symptoms. 

Many parents, teachers, and mental health providers 
may find it easy to conclude that a child has ASD 
based on the broad and vague social criteria. 

What parents need to understand is that ASD is a severe diagnosis. Within that severity, children can be divided into mild, moderate, or severe sub-categories, but they shouldn't be included in the ASD unless they are severely delayed or impaired to begin with. Another important point for parents to understand is that language and social-behavior development has a wide-range of normalcy; it can vary substantially from one child to another and from boy to girl. For example, girls tend to excel at speech and fine motor skills and boys at spacial-relations and gross motor skills. Some boys might not speak at all until age two, while some girls could have a vocabulary of 300 words at 18 months. Many boys will have horrible handwriting, and many girls will struggle with climbing, running, and jumping.

There are ways to differentiate sufferers of ASD from "normal" children. For example, children with or without ASD may have a language delay; however, the child with ASD will be unable to learn language at all or at a very slow rate, whereas the child without ASD will learn much easier. However, because the diagnosis of ASD includes many areas of development, this will not be true in all cases. Under the new criteria, some ASD kids may learn language quite well, but have severe social deficits. Yet many children without ASD will develop social skills much slower than others. In fact, many children will not develop what is considered to be adequate social initiative and social effectiveness until 10-13 years of age, when neurons in the brain bloom and prepare for social development. Experiences like divorce, bullying (victim), or trauma can underlie delays in social skill development.

Don't let reports about the prevalence of ASD worry you. There is probably no reliable way to measure prevalence of ASD. With dramatically increased awareness of Autism and ASD, changing criteria for the disorder, rampant self-diagnosis and misdiagnosis, and inconsistent reporting, there's no doubt that the numbers of kids with Autism is unreliable. 

Even if prevalence statistics were 100% accurate, they would only represent the number of children who have a variety of cognitive, speech, social, and other behavioral problems, not a specific disease.

Case Example (information has been changed to protect identity):
     I provided a second-opinion diagnosis for parents of a 2.5 year old male. The parents reported that they were told by school staff that he was Autistic. He had been diagnosed as PDD NOS by another mental health provider. Even after a basic Interactive Child Evaluation, I suspected that he had been misdiagnosed. His social interaction seemed in a normal range; he paid attention to my facial expressions; he responded to them; he showed interest in sharing toys with me; he was able to follow instructions and learn how to play a basic puzzle game. The parents noted that compared to his sister "when she was his age," he was very far behind. He had good facial symmetry, no facial anomalies. He had no history of gastrointestinal problems. He was a cheerful child who seemed content. He had few, if any, tantrums from week-to-week, and tantrums were mild. 
     What was most apparent was his lack of speech. He didn't talk, but he would follow commands that we would expect a 2.5 year to understand and follow. When I asked about reading and writing time, the mother reported that she had little or "no time" for him during the night; all of her time was spent doing chores and taking care of the older kids. The father would come home from work after his son was in bed and leave before he was awake. During the week, he participated in no reading or writing activities; his father was taciturn. So, neither parent was talking or reading with this child. I told the parents that I suspected that he was not Autistic, that his diagnosis of PDD NOS was probably mild and not a reflection of his capacity to learn and develop, and that they should try spending substantially more time reading to him, talking with him, and writing. I also suggested screening with Easter Seals. At a 2.5 year follow-up, he was mainstream, "doing fine," There was no concern of Autism, Asperger's or PDD NOS.

Mental Health Advice Disclaimer: The information included in this post and blog are for educational purposes only. It is not intended nor implied to be a substitute for professional mental health treatment or medical advice. The reader should always consult his or her mental health provider to determine the appropriateness of the information for their own situation or if they have any questions regarding a mental health or medical condition or treatment plan. Reading the information on this website does not create a therapist-patient relationship.

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