AUTISM: THE NUMBERS DON'T ADD UP
Why we can't be complacent about the autism epidemic.
Posted May 04, 2010
We've just finished Autism Awareness Month. Were we any more aware of autism on April 30 than we were on April 1? I doubt it. Most of the coverage was same-old same-old; none of it got to grips with the meat of the matter, least of all PBS's Frontline in its program "The Vaccine Wars".
Usually, Frontline goes for the jugular--if it's a corporate jugular, so much the better. This program was quite different. It took two extremes, pitted them against each other, and let them scream at each other (of course that's "debate", twenty-first-century style). In the process, everything interesting, including why there's a "war" in the first place, got swept under the rug.
And even at that, the producer's thumb was on the scales. Claiming there was no link between vaccines and autism were authority figures like Dr. Anders Hviid, noted Danish epidemiologist, and Dr. Paul Offit, who holds two UPenn professorships as well as directing the Vaccine Education Center at the Children's Hospital of Philadelphia. Claiming there was a link were people like "celebrity Jenny McCarthy" and "businessman J.B. Handley". The only doctor on their side was the discredited, disgraced and demonized Dr. Andrew Wakefield, whose troubles have been gleefully chronicled in least sixteen Psychology Today blog posts by nine separate authors, only one of whom is listed under "autism" in the blog index (did anyone besides me think, overkill?).
But there's worse. Frontline's treatment suggested that all the real science was on the no-link side. That is simply false. Many doctors and scientists still have doubts, for a variety of reasons. Indeed, two well-respected pediatricians who share such doubts, Dr. Jay Gordon and Dr. Robert Sears, were interviewed for the program, then abruptly dropped--no reason given. (Dr. Sears' interview appears on the PBS website; Dr. Gordon's, which apparently diverged further from no-link orthodoxy, does not.)
A quick look at some of the science. A mainstay of vaccine defenders is the research carried out in by Dr. Hviid and colleagues claiming that since thimerosal was removed from vaccines given to Danish children, autism hasn't gone down, and may even have gone up. Dr Wakefield was excoriated because he took fees from lawyers for his research, but what's sauce for the goose is not, apparently, sauce for the gander; nobody but autism researcher Dr. Bernard Rimland noticed that Dr. Hviid too has a massive conflict of interest. In a letter to JAMA (Journal of the American Medical Association) Dr. Rimland revealed that Dr. Hviid and his colleagues, during that research, were affiliated with the Statens Serum Institute, a for-profit, state-owned enterprise; in 2002, vaccines (some of which still contained thimerosal) represented approximately one half of its revenues and more than 80% of its profits.
Couldn't the research still be valid? Well, in 2005 this (and other similar work) was scrutinized in a review article in the international refereed journal Neuroendocrinology Letters by Dr. Joachim Mutter of Freiburg University Hospital and colleagues from Germany, Britain and the U.S. The authors found a number of serious methodological flaws in the Danish research, including changes in the population (two substantial new groups were added to the study for the years after thimerosal was dropped) and changes in the diagnostic criteria around the same time. Both types of change would make it look as if, post-thimerosal, autism rates weren't decreasing. But after surveying this and a wide range of other studies, clinical and experimental as well as epidemiological, Mutter et al. concluded that "repetitive mercury exposure...is one potential pathogenetic factor in autism". No vaccine defender ever mentions this article.
And that's part of the problem. Vaccine defenders contribute to the rage of the anti-vacciners by a cancerous mix of disingenuousness and condescension. The disingenuousness lies in their pretense that Science speaks with a single voice on the safety of vaccines--they could have gotten away with that in the old days, but now there's this pesky Internet. The condescension lies in their patronizing tone. Anti-vacciners, duped by "charlatans", seek desperately for anything they can "blame". Why won't they listen to us--can't they see our degrees?
I'll tell you in two words why autism should remain a source of deep concern for all thinking people: regression and numbers.
There are countless reports of children as old as three with normal development who suddenly lose language and social skills and regress to an autistic state. What percentage of the autistic community do these represent? We don't know. Nobody seems to be looking, because vaccine defenders tells us it's an illusion. One story was that parents just didn't notice their child's abnormalities until too late. This story, deeply insulting to any parent, has been replaced by a milder version; the "regressing" children had actually, all along, shown "subtle signs" of abnormality that only expert eyes could spot (remember the old bio-lab adage," Believing is seeing"?) Vaccine defenders seem determined to cling to the Gospel of Genes and rule out any environmental causes.
As for the numbers, we all know them--at least a twentyfold increase in a quarter-century. Sure, some of that increase is due to broadening definitions, to the inclusion of many milder cases plus some that would have been diagnosed as simply "retarded". But if that was the only factor involved, the number of cases that would have been classified as autism in 1985 should have remained more or less constant until today. Have they? We don't know. Moreover, rates in California started to rise steeply in 1988, six years before DSM IV broadened the definition.
If vaccine defenders wants to shut the anti-vacciners up--and that's understandable, given the thousands of children's lives vaccines have saved--they should as a minimum give a proper accounting. We need to know how the autism spectrum divides up--how many AS, PDD and Asperger's cases there are now and were five, ten, fifteen years ago. We need to know, for each of these categories, the percentages that have undergone regression and whether these have changed over the years.
And of course we need less disingenuousness and less condescension. Right now, the "Vaccine Wars" are a prime case of what happens when policy issues are allowed to trump the search for truth.