Explaining the rise in the autism rate

A recent report stating that one in 50 school children carries an autism diagnosis appears to confirm anecdotal evidence that we are experiencing an increase in the autism rate.

But there are a number of things that should be considered in a discussion of these findings — and leading that discussion should be methodology.

These new data from the CDC’s National Center for Health Statistics (NCHS) are culled from a 2011-2012 survey of parents who were asked about autism spectrum diagnosis among their children ages 6 to 17.

A year ago the CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network, which based its findings on review of school and medical records and limited its scope to data on 8-year-olds, put the autism rate at 1 in 88.

The ADDM used records from 2008 in its analysis, and it concluded that the rate represented a relative increase of 23% from 2006 and 72% from 2002.

Two different reports from two different entities within the CDC using two different methodologies for data collection — yet the take-home message is the same: more and more children are being diagnosed with autism.

And the authors of the NCHS report point out that it is the prenatal period that is “the key exposure window for ASD risk factors,” which, they say, makes it unlikely that changes in autism prevalence among school children “reflect ‘true’ increases in susceptibility to the condition at these ages.”

What does appear to be happening, the NCHS researchers wrote, is that more children with mild autism symptoms are being identified and formally diagnosed.

Given the greater awareness of autism among both physicians and parents and improved diagnostic techniques — there is now evidence that autism can be diagnosed as early as 18 months — the evolving scenario is likely to include more evidence of an increase in prevalence at least in the near term.

Moreover, autism diagnosis rates will also change with the implementation of DSM-5, which will be unveiled at the American Psychiatric Association meeting this May.

As it now stands with DSM-IV there are four autism spectrum disorders, all of which will be compressed into a single diagnosis with additional specifiers.

That change has already been widely criticized by those in the autism community, who claim it will make it more difficult for some children to access services, but at the same time move those with Asperger’s syndrome into an autism diagnosis.

It is difficult to gauge the impact the DSM-5 change will have on prevalence, although it is tempting to take the cynical view and say it will contribute to a leveling out of the increase — especially given the concern about the lifetime costs of autism.

Sanjay Gupta is editor, The Gupta Guide at MedPage Today, where this article originally appeared, and chief medical correspondent, CNN.

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  • Noni

    I’ve always been stunned that no one considers the increase in diagnosis in (1) the desire to label kids and (2) the desire to provide these kids services early on. I think early intervention is great, particularly when you have a diagnosis to work with. I am highly suspicious that all these new “autism” cases are actually autism. What I suspect is that through broadening of definitions many more kids fall onto the “spectrum” and are entitled to services. This is one area I have no complaint sending tax dollars to. Whether or not kids are actually autistic or not, I think many could benefit from early intervention, so the diagnosis/labeling serves a purpose.

    • Guest

      How does the rise in “officially diagnosed” autism cases correlate with the financial incentive for parents and schools to have children “officially diagnosed” with “autism”?

      When you subsidise or financially reward something, you generally get more of it. And once a shy or awkward child is a money-maker for the vested interests (parents, schools) receiving the cheque, there’s not just a disincentive but an actual financial loss to helping the child recover.

      We are creating a taxpayer-funded Victim-Industrial complex.

  • Stacy

    Noni, I have two autistic children. One is seven can’t communicate verbally, has no idea when he is pooping his pants and seizes while he sleeps. Is he autistic by your standards? Is it ok to label him?

    • Noni

      So out of curiosity, how do you feel about the children who are sensitive to loud noises or are socially awkward or fall somewhere on the spectrum (who, 10 years ago would have just been labeled as eccentric) now taking services intended for your severely autistic child?

  • http://www.facebook.com/people/Steven-Reznick/100000549195050 Steven Reznick

    Years ago I heard an American President declare war on cancer. Those efforts and that funding have benifitted millions of people worldwide. We need a similar effort in identifying the causes , risk factors and issues that contribute to this horrible developmental disorder(s)afflicting our youngest and most innocent victims. I attended a lecture two weeks ago at which a prominent nephrologist reported on the contamination of commonly sold vitamins , minerals and supplements with heavy metals. Produced outside the USA and no longer inspected by the FDA due to legislation championed by Senator Orrin Hatch to benefit his constituency, the question is no longer whether the main ingredient helps or hurts but what contaminants in the bottle are killing us. The speaker, W Kurpin MD, pointed out that the target market is women between 18-45 and he estimated that their heavy metal levels just might be elevated in 35% of the women of child bearing age. This is just one factor with adults of child bearing age being exposed to multiple assaults and insults with chemicals, all forms of radiation and communication transmission waves. Our hearts and prayers go out to the children and parents fighting to make better and more productive lives for their families . They need our support morally and financially.

  • querywoman

    I am a high functioning autistic with mild Asperger’s Syndrome. I didn’t get dx’d till my forties, and I understand things about myself when I got dx’d, like why I can’t tolerate dogs or noise.
    I have a friend who is a teacher’s aide in a high school for low functioning autistic teens , some still in diapers. In our state, they can still in school til they are 21. She said a few will be able to get jobs.
    Of course, with affirmative action, there are other kids labeled retarded but not autistic in different kinds of classes.
    Not so long ago, people like that didn’t exist in regular society. They were locked up in state schools and forgotten.
    Now that we have a word for them, they get supportive therapy (maybe not the best word), to help them function a little better.
    Maybe by identifying their syndrome and labeling these kids, they are living longer than someone labeled retarded and shut away in an institution.
    No matter what your illness or diagnosis, most people will live longer with tailored therapies, love, and attention.

  • Steve L

    It really doesn’t matter what the “label” is so much as the cause being found. Nearly all of these kids grow into not-so-functional adults who are in need of social skills training, legal representation and medical intervention just like my son. If the governments/thinktanks of the world don’t investigate the cause, it will cost them much more than the research in the long run. It would free-up hospital beds and prison cells. As a parent of one of these children I hope no-one else has to go through the living hell that we have.