Thursday, October 8, 2009

Why the increase in autism rates? More awareness? Or more misdiagnoses?

A Department of Health and Human Services report released Monday says that the autism rate in the U.S. is higher than previously believed -- about 1 in 100 children have an Autism Spectrum Disorder (ASD), the report says, up from the previous estimate of 1 in 150.

The details are even more troubling: The report, which appeared in the American Academy of Pediatrics' journal, Pediatrics, shows that while the 1 in 91 children are on the autism spectrum, the rate for boys is a startling 1 in 58.

Why the sudden uptick, especially given that the rate was just raised to 1 in 150 earlier this year? Over at's Child Caring blog, I'm asking my readers what they think.

"Increased awareness" is the easy answer. A generation ago, a child with autism would simply have been labeled "difficult" or "quirky," but we have a better idea now of what to look for (and how to help). Another possibility: The autism spectrum itself has grown to include things like Attention Deficit Disorder, Attention Deficit Hyperactivity Disorder, Asperger's Syndrome, and the all-encompassing PDD-NOS, or Pervasive Developmental Disorder Not Otherwise Specified. Whatever the reason, the results of the study, culled from the responses of more than 78,000 parents, can't be ignored.

(Back in April, I wrote a four-part series on autism as part of Autism Awareness month -- you can read them all here. )

No one really knows what causes autism. A recent article in Science Direct indicates that children living near toxic waste seem more likely to have autism. Though the link between Thimerosal and autism has not been scientifically and definitively proven, many people still support the theory, citing anecdotal evidence that the mercury-laced preservative triggers a toxic tipping point, damaging the immune system. Others believe that a toxic synergy is to blame; many of the studies disproving the Thimerosal/autism issue do not explore the effect of multiple vaccines administered simultaneously, and many of the "harmless" chemicals and additives in everyday food and consumer products become toxic when heated or combined. (Randall Fitzgerald's book, The Hundred-Year Lie: How Food and Medicine are Destroying Your Health, does a great job of explaining the concept.)

Children who were extremely premature are thought to be at higher risk for autism. In 2008, some studies showed a possible link between autism and certain metabolic diseases. And of course, there's the genetic link: “Autism is probably caused by many, many things, most of them genetic, and this is one of them,” mitochondrial expert Salvatore DiMauro of Columbia University and the author of a study of autistic individuals with mitochondrial disease, tells the Simons Foundation Autism Research Initiative.

In spite of not knowing the cause, and in spite of not having a cure, a device has hit the market that claims to offer parents a way to detect autism in their child early on. The LENA Language and Autism Screen is raising red flags in the medical community. The device analyzes speech patterns in 2- to 4-year-olds, but not all children with speech problems are autistic. And, as Dr. Susan Anderson, director of the Autism Clinic at the University of Virginia Children's Hospital, told ABC, autism "is also a disorder of non-verbal communication, a disorder of social development (including play skills) and interactional skills, and a disorder which includes atypical behaviors. Any means of screening for autism needs to include all of these measures."

Our 11-year-old son is on the spectrum and I'll admit that, after his diagnosis with Asperger's Syndrome more than five years ago, there was a point where I felt like I was seeing signs of autistic behavior in nearly everyone I met. According to the study in Pediatrics, "Nearly 40 percent of those ever diagnosed with ASD did not currently have the condition." Does that mean that Autism Spectrum Disorders fade away with time? Or that maybe more kids are being misdiagnosed with ASD in an attempt to explain their not-quite-perfect behavior?

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