Needed: More (Complete) Autism Research

April 4, 2006

I hate these health stories: Most news networks and publications yesterday ran a story attributing the spike in autism cases in recent years to a “labeling” issue rather than an epidemic. According to researcher Paul Shattuck of the University of Wisconsin in Madison, children in special education programs classified as “mentally retarded” or “learning disabled” are now more frequently identified as “autistic,” which suggests that there isn’t an actual increase in autism cases, but a more precise diagnosis of learning disabilities.

Autism, by the way, is a brain disorder that leads to diminished social skills, delayed speech, and weird responses to sensations. As many as six in 1,000 children have the disorder, according to CNN’s story. I even had an autism scare when my shy 18-month-old son barely spoke a word and the doctor asked to see him again for a “speech check.” I noticed that our pediatrician kept attempting to make eye contact with him, and despite her reassurances, I still hurried back home to my computer and googled in “autism.”

Thankfully, my two-year-old boy, a chatterbox in both Spanish and in English, passed the dreaded speech check.  

Still, it isn’t clear what exactly triggers autism. Because of the surge in the diagnosis in the Silicon Valley and Bay Area, Wired Magazine four years ago questioned whether there was some “math-and-tech gene” to blame. There is a public concern that vaccines containing a preservative with mercury called therimerosal — which is no longer used, according to CNN — caused the surge in autism cases in the 1990s and turn of the 21st century.

Shattuck’s most recent study may allay some fears, but this is what gets me: In this very same news story, he admitted that some unknown environmental factor may trigger autism. Another autism researcher, Craig Newschaffer of Johns Hopkins Bloomberg School of Public Health in Baltimore — which happened to be the end kicker to CNN’s story — challenged Shattuck’s study:

“We do not know whether individual children have switched classifications, and of course we can never know whether a given child in a particular birth cohort would have been classified differently had they been born either earlier or later. At best, analyses of this type are merely trying to determine if trends in one classification have the potential to offset those in another,” he wrote.

There was a clear need for definitive studies into the roles played by genetic susceptibility and environmental triggers in autism, Newschaffer wrote.

So, which one is it? I understand the media’s need to balance its news with various viewpoints, but when it comes to public health issues, I really wish we had more definitive answers.