Friday, January 22, 2010

Denials Do Not Explain Autism Epidemic, Environmental Factors Must Be Researched

If any disease or disorder saw startling increases from 1 in 500 to 1 in 110  in just over a decade it would be taken seriously. Unless of course the disorder in question is autism where a significant number of professionals  are joined by Neurodiversity ideologues in denying  the existence of an autism epidemic. The deniers hold religiously to their beliefs without an explanation for much of the startling increase in autism diagnoses.

The autism epidemic deniers rely heavily on the 1994 change in autism diagnostic criteria and definitions, diagnostic substitution, increased autism awareness and other ascertainment factors. While there is no dispute that these factors play substantial roles in accounting for the upswing in autism diagnoses they only account for approximately 50% of the increase in autism diagnoses, leaving 50% of the increase unexplained. Given the startling rise in autism diagnoses 50% of that increase represents in itself a startling increase. Yet the deniers blithely assure the world that there is no real increase in autism diagnoses.

The view that 50% of the increase in autism diagnoses is unexplained by diagnostic change, substitution and ascertainment factors  can not be pinned on  a celebrity actress or holistic doctor frowned upon by the "scientific community". Doctors Novella and Gorski and Neurodiversity ideologue Kev Leitch can not use "scientific" terms like "woo" and "quack" to dismiss  the opinions of Dr. Thomas Insel, director of the Interagency Autism Coordinating Committee, who  has stated in an interview with journalist David Kirby that 50% of the autism diagnoses increases reported in the California study is unexplained by  diagnostic change and ascertainment factors:

"It looks like about 24 percent of the California increase can be attributed to something like a change in diagnosis criteria. They are beginning to use multiple diagnoses. So that children before, who were listed simply as mentally retarded rather than autism - but they had both - are now logged in with both. But that really caps out at around 24 percent. There’s probably another piece of this, which globally could be attributed to ascertainment. But that caps out at around 16 percent, or something like that. And when you put all of that together, you are still well below explaining 50 percent of the increase.

So what does that mean? It means that, as far as I can tell, the burden of proof is upon anybody who feels that there is NOT a real increase here in the number of kids affected. Because all of the evidence we have up until now says that, well there are what we could call – I wouldn’t call them ‘trivial’ factors – but they are factors that are not related to incidence, but would be simply related to prevalence, like ascertainment. But they don’t really explain away this huge increase.

This tells you that, you really have to take this very seriously. From everything they are looking at, this is not something that can be explained away by methodology, by diagnosis. Some piece of it can, but the whole thing can’t.""      [Bold highlighting added. HLD]

Having rejected the diagnostic and ascertainment factors as complete explanations for the increases in autism diagnoses Dr. Insel then went on to reject the theoretical basis of autism epidemic denial, the assumption that autism disorders result entirely from genetic factors and the fervent belief that environmental factors do not play a role in causing autism disorders:

"I don’t think anybody is arguing that it is 100-percent genetic. I mean, I think that there are just a lot of questions that this raises. And I don’t think in those terms, exactly, that it’s either genetic or it’s environmental. From my perspective, it’s almost always going to be both. And the only question is: How do you nail down this interaction, how do you go after it?


There is no question that there has got to be an environmental component here. The problem for us has been trying to find the right way to get our hands around it, and to identify what that is most likely related to  ...     in the last few months, or maybe year, we’ve begun to develop the tools that will allow us to get at this. And these tools are from this whole emerging field of epigenetics, or epigenomics.   And in this case you are not looking at genetic sequence - which is what we’ve been doing for the last decade - but you’re looking at how the DNA is bound up with all kinds of proteins. That is largely affected by experience, or by environment. Some of it is probably hardwired, but a lot of it has to do with exposures, particularly early in development but even, as we are learning, even after birth

So what we are really excited about here, I think, is to be able to use these new tools. And what has only happened in the last month or two is the first whole genome epigenetics effort, where we have been able to say, ‘We can map this entire aspect of genomic biology, and it tells us what someone’s exposure history might have been.’ It shows you effectively, or we are hoping it will show us, where the scars might be from early exposures."

The near 100% focus on genetic based autism research over the last decade, referenced by Dr. Insel, was identified by Terersa Binstock in 1999.  That focus has resulted in little research of the environmental factors involved in causing autism disorders.  The failure to study possible environmental factors in causing autism has allowed autism epidemic deniers to claim that there is no evidence of environmental factors in causing autism, that autism is entirely genetic and that there is therefore no autism epidemic since a purely genetic disorder would not show dramatic increases in such a short period of time.

Given the recent CDC data, and given the emerging scientific view reflected in IACC Director Insel's statements in the Kirby interview it appears time is now running out for the autism epidemic deniers. 

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farmwifetwo said...

And since they can't prove with their gene research that my autistic disorder son and yours have the same damanged genes, YET, have the same diagnosis... Let alone those with Asperger's or NLD or Rett's or....

Means the "genes" only theory doesn't deal with the increase in diagnosis at all.

I did see - tv/online?? can't remember - lately that they were talking about dx'ing children with autism with MRI's one day... That would be the best way to debunk the "self-dx" crowd if they could find a test that would work....

blogzilly said...

That's a great read, that data. Thanks for sharing it.

Anonymous said...

As for the "epidemic" -- diagnostic substitution accounts for about 1/4 of the increase, as noted. There is also a considerable increase because of people being diagnosed now who would have received no diagnosis whatsoever 10-20 years ago -- due to better awareness, due to better access to an informed medical system and services, due to research which connects more symptoms to ASD, several factors. (Related: "where are all the autistic adults?" Well, many autistic kids grow up to be perfectly functional adults, if a bit socially unskilled, and that is entirely without treatment -- autism isn't "cured", but kids grow and improve. And if anecdote is important to you, then I personally know two people in their 40s who are definitely autistic, not diagnosed, who would definitely have been diagnosed autistic if born in the 90s or noughties.)

Another issue is that because of awareness and education of medical professionals, and research into what autism looks like at younger ages, kids are being diagnosed younger than they were; that is, in the 90s many children would only have received a formal diagnosis at school age (5-6) or possibly even later, around age 7-8; now, an increasing number of children are diagnosed at age 3-4, and it is being pushed back to age 2 as doctors learn what symptoms of autism look like in children that young. This means that when you look at the diagnostic rates for these age brackets, they are much higher than they were ten or 15 years ago. Diagnosis of 3-yr-olds now is way above diagnosis of 3-yr-olds 15 years ago, but that is not prevalence, it is detection and recognition.

There is also an issue of rural vs. urban populations. Even now, with increased surveillance, awareness, and access to services, kids from rural populations on average receive diagnoses a year or so later than urban populations. Ten years ago it was worse; rural kids might not get a formal diagnosis at all. Now, you would think that this is simply a repeat of the point made above, but there is an added dimension: over the last 30 years, there has been a flood of people out of rural areas and into urban ones, as small farms fold. This shifting demographic means more potentials are in the catchment area for better diagnosis.

Anonymous said...

The near 100% focus on genetic based autism research over the last decade, referenced by Dr. Insel, was identified by Terersa Binstock in 1999.

Are we talking about this Teresa Binstock?
Teresa Binstock has a bachelors in Math and has been playing scientist for some years now. Her main type of "research" now is monitoring parents' listservs and noting what they say about their children and mercury poisoning and how they respond to stuff like cilantro, red wine and saunas (chelation therapies). She has a "foundation" or something with a goofy name and which consists of her, alone.

Binstock has a paper where she says that upset intestines are connected to a part of the brain that controls some aspect of speech. She thinks that the upset intestines cause speech problems, either that or viruses are travelling up the neurons from the intestines to the brain, where they do some unspecified damage. She gets at this by reading various research and combining what she learns from the papers.

Just checking....

Unknown said...


Your personal attack on Teresa Binstock adds nothing to the discussion. Your comments here have tended to be based on similar hostile emotions. Very disappointing.

Teresa Binstock's disclosure that autism research funding had to be genetically rather than environmentally focused has not been rebutted by anyone.

To the contrary if you read the comments by Dr. Thomas Insel, Director of the IACC, (that stands for the Interagency Autism Coordinating Committee in case you were unaware) acknowledge the overwhelming emphasis on purely genetic factors in the remarks I quoted in my post. Dr. Insel noted that the new direction is to examine the interaction of genetic and environmental factors in causing autism.

Ms Binstock's depiction of the "it's gotta be genetic" model of autism research funding was also confirmed 10 years later by
Irva Hertz-Picciotto, UC Davis M.I.N.D. Institute Researcher:

"Right now, about 10 to 20 times more research dollars are spent on studies of the genetic causes of autism than on environmental ones.
We need to even out the funding."

I hope this information helps bring you up to speed on autism research issues and helps you overcome your anger at anyone who attempts to discuss autism disorders as anything other than purely genetic.

Unknown said...


Thank you for offering your comments. The diagnostic change and ascertainment factors were considered and accounted for in Dr. Insel's comments. As director of the IACC he has certainly ample access to the research on which to base his conclusions.

AFTER the diagnostic change and social factors are accounted for 50% of the stunning increase in autism diagnoses are still unaccounted for.

Hopefully a redress in the imbalance between funding of entirely genetic and environmental factors involved in causing autism disorders will help identify the environmental factors.

Unknown said...

blogzilla, you are welcome.

Luna_the_cat said...

The comment visible was meant to be one of 4 or 5; I had to split it due to length. I apologise for glomming up comments like that, but on the other hand, I wouldn't have said it if I hadn't thought it was important. Are those comments still there awaiting moderation, or has the blog software eaten them?

Regarding Insel, and/or the actual prevalence of autism vs. better detection (i.e. ascertainment): reading that interview, he has "feelings", but what he doesn't have is technical justification for the 50% number. I've seen thorough technical analyses of autism reporting/detection/diagnosis changes, several from outside the US -- and yes, I will make an effort to dig up the paper references -- which put the true rate of increase at closer to 2-3%, not 50%. All of the authors of these papers made the point, this is still too much, and we need to find out what is behind it -- but technical accuracy in what is happening is very worthwhile, IMO.