Archive for the ‘Prevalence’ Category
The Fairytale of a Static Rate of Autism Part 5 – The Prevalence Jackpot Versus The Prevalence Hookup, Futilely Struggling To Making Sense Out of Static, And How Journey Autism Flavors Our Path Of Moving Forward
Posted April 17, 2013on:
Hello friends –
There used to be a poker room about twenty miles from my home; it sat above a run down greyhound racing track and smelled like an old shoe on the best day. But they had poker. They hosted an accumulating jackpot hand, usually worth a couple of thousand dollars, sometimes quite a lot more, which you could win if you got a royal flush in the current suit; i.e., if the suit was hearts, and you wound up with 10-J-Q-K-A hearts, you’d win the Jackpot. This could lead to some unusual cost/reward analysis scenarios.
Let’s say you sit down to play and buy in for a hundred dollars. Then, three hands later, you look at your two hole cards and you have 10-J hearts. Not really a great hand, but if the board winds up showing Q-K-A hearts somewhere in the next five cards, you win fifteen thousand dollars (or whatever the Jackpot had accumulated to). Almost everyone folds, but before you get a chance to see the next three cards for the two measly dollars you put up as a blind, an aggressive, serial over-better to your right raises to fifteen dollars. You are in a tough spot, you know the guy bets like crazy anytime he thinks he can steal a pot, but you still are losing to anyone with a queen. If you had 10-J spades, or clubs, or mixed, or (nearly) whatever else, this is easy; you dump your shitty cards. But with your two royal heart cards, you *could* win the jackpot; your odds still totally suck, even if you were getting paid off a thousand to one you still didn’t have the ‘right’ odds to make the call, but if you inhabit a place where losing fifteen dollars won’t kill you, but winning fifteen thousand would definitely be a game changer, the magnitude of the potential winnings must be part of your decision making process.
I called the raise a few times, but never hit the jackpot. Or even came close.
I keep coming back to the idea of incorporating the scale of potential outcomes when I think about the non event of the hilarious prevalence numbers that came out a while, one in fifty with ‘autism’. Nobody outside of Journey Autism fucking cared and the responses were depressingly predictable; the media and the Internet skeptics went ‘full awareness’, and found nothing of any alarm in these numbers, the Internet vaccine crazies went ‘full autism’, and assumed the numbers were solely comprised of individuals who would need 24×7 assistance for forever. It was all a big joke. Haha.
I don’t know how large the real increase in autism is (the older parental age data tells us unambiguously that some of the increase is non-imaginary), but I do know that as our best efforts at figuring this thing out has left us skipping from one in two hundred and fifty, to one in a fifty in eight short years. To my eye, this means a real increase of fifty percent (or more!) could easily be hiding in the static and we’d never know. Most everyone doesn’t seem to care, that is the way of the Prevalence Hookup, quickly embracing whatever prevalence numbers come out, coupling until a set of newer, bigger, even more ‘greater awareness’ numbers come along.
But my thoughts continue to be formed by concept of a sort of missed jackpot opportunity when I see a sense of complacency about our ever growing autism population; it isn’t that I don’t believe that diagnostic changes and the watering down of what a diagnosis means in terms of life skills aren’t affecting rates, those factors are clearly at play, but the ramifications of just “some” of the increase being real seems like a big, big, big deal to me. When your population of interest is every child, a small real increase means a lot of individual children are affected. Sure, it is, possible that older parental age is the only recent development that is affecting rates upward, with all of the rest being diagnostics, but I find little comfort in this notion. If the soft social scientists are wrong, even a little, and there is a true increase in incidence, we may come to regret the solace provided by our collective bobbleheading at the mantra of ‘greater awareness’, for it enabled us to waste a great amount of precious time.
The thing is, it doesn’t really cost us that fucking much to apply more resources to the unimportant, nagging question on the neurodevelopment of a generation of infants. In 2006, Bush signed the ‘Combating Autism Act’, a bill included a billion of dollars for ‘research, surveillance, and treatment’. That’s two hundred million a year. Last year, The Avengers, a stupid and shitty movie, made over a billion dollars. Now, I know there are other funding sources for research, surveillance, and treatment, but there were also a lot of other stupid movies.
I believe that this prioritization is the equivalent of folding 10-J hearts to a dinky four dollar raise; the knowledge we could gain from a relatively small outlay is worth a lot. We shouldn’t be worrying about the cost, we should be considering the payoff; the question we are trying to understand, “are today’s infants neurobiologically different than infants of the last generation?” has a difficult to understate payoff. We shouldn’t be embracing reasons to stop playing, we should chomping at the bit to see the next three cards. This is an easy call.
And yet, there was a collective yawn when the CDC announced 2%.
Funny enough, it was just a few years ago that the UK NHS study of adults found a prevalence of 1%, a finding which was heralded as remarkably strong evidence that autism rates are stable (at the time, 1% was the general value for US children. Oh well.). For some reason, the robustness of the NHS adult findings didn’t cause anyone to exclaim that there is a sort of epidemic-lite, what with US kids having autism as twice the rate as NHS adults. It was a classic case of doublethink; US kids have autism at 2%, England adults have autism at 1%, and autism rates are stable. (Believing that any of the numbers have validity might be closer to triplethink!)
A while ago I saw an interview with Fombonne on the SFARI site that contained the unsurprising byline: ‘Eric Fombonne says that the new CDC report does not necessarily mean that prevalence is increasing’. [Note: This was BEFORE the 2% numbers were reported!] Anyway, he made some interesting points about the messiness of the autism data showing how silly the state by state numbers are; Utah has four times the cases that Alabama does, and utilized different diagnostic methods. In the text of the interview, he reveals Utah also had very low levels of MR (~ 13% instead of ~ 28%), AND had a creepy low male to female ratio. Either there is something really weird going on in Utah, or the ‘numbers’ from Utah and Alabama are not measuring the same thing. It could also be that the numbers are measuring some of the same thing, and there are a couple of weird things going on in Utah (heh). But the bigger point should be that we shouldn’t expect to get a decent understanding of autism rates at a national level by clumping together Alabama numbers, Utah numbers, and whatever other numbers, shaking up them up, and averaging them out. Maybe the headline ought to read, ‘Pretty much somewhere between half a percent, and two percent of children might have something a psychologist, or a doctor, or both, have something called autism, the manifestations and lifelong impact of which vary considerably individually and regionally’, or maybe ‘Autism Rates: Your guess is as good as ours!’.
I don’t trust any set of numbers more than an educated stab in the dark.
[Note: for a slightly different take on ADDM numbers, you can see this interview on SFARI, where Walter Zahorodny reports that detailed analysis of NJ data indicates a likely real increase in rates. Doh!]
I began to wonder; if almost nobody really seems worried about an ‘epidemic lite’, if no almost no one is alarmed that the confidence intervals in our data could incorporate huge numbers of actual people, why am I so concerned? Is my version of the precautionary principle overly cautious? I don’t know the answer to these questions, but I think that part of the answer lies within my journey autism, watching my son’s challenges (and triumphs) unfold, and the knowledge that whatever we find about autism incidence, he will be reliant on other people for his survival for his entire life. That is the gift autism has given him; it doesn’t mean he can’t be happy, it doesn’t mean he can’t experience love, but so far, we cannot detect that autism has provided him anything other than near debilitating OCD, an imperfect sense of dangerous situations, and a lifelong requirement of the kindness and capabilities of others.
I am filled with a pervasive and soul crushing sadness at the possibility of one ‘extra’ child having the same challenges because of changes we have collectively made to the environment, and that is the heart of the semantic dance over how much of the increase is real. That is the Jackpot.
But, your mileage may vary. I know that there are some parents and people out there who have challenges as heavy as my son’s, and they don’t share my sense of panic over the issue. A lot of people credit their autism with benefits. I won’t discount their experiences. Part of the reason we don’t see eye to eye may be that we look at the same question, but see different risks, and different payoffs.
The Fairytale of a Static Rate of Autism Part III – Prevalence Hookups or What if They Threw An Autism Epidemic And Nobody Cared?
Posted May 30, 2011on:
Hello friends –
The osmotic pressure of cool people and pop culture tells me that what we used to call one night stands are now called ‘hookups’, casual sexual encounters as convenient that don’t necessarily mean people are dating, but some release can be found, and everyone moves on with their lives until the next time. This reminds me a lot of how people that ought to know better have been treating autism prevalence studies lately. The results are useful in cementing an already reached conclusion, but ultimately, the findings are only used as isolated ejaculations of the same ideological tweets. Last week’s hookup doesn’t mean anything come this Saturday night, and there is absolutely no reason, no reason, anyone should be troubled to compare this weeks findings used to trumped a static rate of autism with last weeks findings. What we are witnessing is the equivalent of a scientific one night stand, and anyone who doesn’t think the scientific method should be framed for the sake of expediency ought to be furious.
These posts can oftentimes take me a long while to complete, so dating my start point a bit, about two weeks ago, the NHS study from England came out that described a near 1% prevalence of ‘autism’ in adults. The ‘findings’ from this study actually came to light and received attention in the autism community over a year ago, but the real publication happened in May 2011, so there you are.
About a week ago, the Korea ‘study’ on autism came out; it hit the web with a large footprint, and amazingly, described an atmospheric autism ‘prevalence’ of autism of near 2.5%, with 1 in 38 (!!!!) Korean children ‘estimated’ to be on the autism spectrum. If it has not happened already, this study and ‘conclusions’ will soon became part of the autism lexicon; an uber-Kevlar argument, impervious to any concerns involving the possibility of an actual increase in the number of children with autism.
Both of these studies share very similar methodologies; essentially a lot of people were screened through a questionnaire, a subset of people with ‘high’ scores on the questionnaire were subsequently retested with standard tools for assessing autism. Based on how well the questionnaire did at predicting autism spectrum diagnosis, an extrapolation, with various ‘corrections’, was made as towards how many people in the general public are on the spectrum. In both studies, the overwhelming majority of people ‘estimated’ with autism were previously undiagnosed and were not receiving any services.
Here’s the thing that is driving me up the wall crazy, apeshit mystified and enraged. Nobody cared. Let’s look again at what these studies found and see if we can detect anything of potential interest in their conclusions when compared between one another.
Nobody, and I mean nobody, took these two studies as evidence of an autism epidemic, despite the fact that here we have two supposedly (?) well designed studies that found entire spectrum sized differences in the number of children and adults with autism! You could literally drive the old spectrum through the hole in the new spectrum! If both of these two studies are meaningful, if both have accurately captured autism in their respective target populations, we have no choice but to admit that the epidemic is real, and we have proof that children have an autism spectrum disorder two and a half times more frequently than adults. There is an epidemic of autism in our children; or at least, in Korean children!
Did anyone see those headlines that I somehow missed? Did the online skeptical community acknowledge that we now finally have some solid evidence that indeed, autism rates are higher in children than adults, and somehow I failed to see those conversations?
Here’s what really confuses me. Some of the same people, same ‘skeptics’, and same news organizations breathlessly reported both of these findings without, apparently, understanding their implications alongside one another. For example, in 2009, here’s a post from Stephen Novella at Science Based Medicine that touched on the England study that includes this nugget:
They found a consistent prevalence of 1% in all age groups they surveyed. This is remarkable for two reasons – first, they found the exact same 1% figure as the CDC US survey (assuming the CDC data is more accurate than the phone survey published in Pediatrics). This supports the conclusion that the 1% figure may be close to the true prevalence of ASD in the population.
Second, the NHS study found that the prevalence of autism was the same in all age groups, strongly suggesting that true ASD incidence has not been increasing over recent decades and supporting the increased surveillance and definition hypothesis.
Check out how ‘remarkable’ Mr. Novella thinks the 1% matchup between English adults and American children is in terms of making the case for a static rate of autism. This is a guy whose posts outside the autism realm I tend to enjoy in many instances, he is clearly a superior intellect, and applies a very skeptical eye towards his non-autism posts. My presumption is that he was well aware that the NHS study actually diagnosed a grand total of 19 adults, and had good reasons, which he declined to illuminate in that post, for why this relatively low number of results was immune to significant confounding problems, which is why it provided such ‘remarkable’ evidence ‘strongly suggesting that true ASD incidence has not been increasing’.
Then, in May 2011, Mr. Novella posted Autism Prevalence Higher than Thought, concerning the Korea study. Here is a snippet from the conclusions:
This study adds an interesting data point to the whole picture of ASD. If correct, then the theoretically upper limit of ASD prevalence is about 2.6% of the population, more than twice the previous estimate. It also indicates that when you undergo a program of thorough searching, you will find more diagnoses.
What is going on here? The England study, which found a prevalence of 1%, the study that previously was found to be remarkable evidence of a static rate of autism was exactly the same type of study, wide-scale screening for likely candidates within the general population, followed by targeted autism assessment of people with high scores, and backwards extrapolation. Does anyone think that the Korea study was that much more thorough than the England study? If a study came out tomorrow that reported 5%, or 10% prevalance, would we simply assign this to a even more strenously executed methodology? Is there any evidence that we might use to suspect a 5% prevalance reported next week in Columbia is faulty that could not also be applied against Korea?
For what reason should we, now, believe that the England study of adults was so fatally flawed that it missed more than one autistic adult for every one it found? Surely a study capable of missing more than half of the autistic adults had some type of warning signs back in 2009 that might indicate that the evidence might be less than remarkable, maybe questionable, or that, in fact, it might be a Fairytale?
Am I cynical to suggest that what really made the England study such remarkably ‘strong evidence’ of a static rate of autism was that, at the time, it had findings within the statistical range of existing CDC numbers in children? Was the online and media love affair with the England NHS study little more than prevalence hookup? Have I reached the theoretical limit of jadedness?
There really isn’t a way to reconcile these two findings without either accepting a two and a half times increase in autism in children versus adults, a sort of epidemic-lite, or accepting that one or both of the studies suffer from serious flaws. But if we start accepting that the studies might have serious problems, we shouldn’t be saying they are ‘strong evidence’ of anything, except, perhaps, the difficult to overstate problems of autism prevalence studies. Of course, it is a different ballgame if you are relieved of the intellectual responsibility of actually trying to reconcile the two findings; if you allow yourself the prevalence doublethink that England has meaningful data, and so does Korea, and that the rate of autism isn’t increasing, then, no harm, no foul Big Brother.
One prevalence study that didn’t get the booty call was Brief Report: Prevalence of Pervasive Developmental Disorder in Brazil: A Pilot Study, which came out in February, 2011; just three months before Korea. Methodology wise, this study is a kissing cousin to Korea and England, a screening was performed in the general population, and assessments were subsequently performed and then statistical extrapolations were performed to reach a prevalence rate. Let’s see what these values look like up against each other, and see if we can detect a pattern.
Can anyone see a pattern here?
Now the skeptic might tell you that the Brazil study was a lot smaller, which is true; the initial screening of children only contained a little less than 1,500 children. But it hardly matters; just to get to the level of English adults ‘found’, they would have had to miss two children for every child they found, and to approach Korea values, they needed to have missed almost nine children for every child actually diagnosed. Does anyone think this is reality? Why would prospective screening and backwards extrapolation be so accurate in one population, and so wildly inaccurate in another population? The Brazil and England study used versions of the same screening questionnaire!
I understand that being partially funded by Autism Speaks, and having a ‘cultural anthropologist’ with a book on the subject of autism carries some weight in the press conference area; so that might explain why one study got press, and another didn’t. Forgetting the press issue, where are the calls that we should try throwing four thousand Brazilian genomes at a sequencer to see what in their genetic makeup appears to be protecting them from autism so effectively? Why aren’t these studies meaningful evidence of some environmental force acting to create wildly different rates of autism in these different populations?
I would note that the press releases, media regurgitations, and skeptical viewpoints nearly all contained the boilerplate note that more studies are needed. Consider, however, if our need for ‘more study’ is so extensive, if we place so little confidence in our methodologies that papers published within months of each other, with nearly identical study methods, find literally nine times higher rates of autism in one population aren’t a warning sign of an real difference in incidence, what this ought to be telling us is that all of our prevalence data are crapshoots, at best. We shouldn’t get to pick and choose which studies we think are meaningful because they happen to meet comforting quotas, or discard those that fail to support those palliative notions.
It is tempting to look at the Brazil study and evaluate for design or implementation problems that could cause such startlingly low rates of autism; the authors go into some discussion about the reasons their findings might seem so low. Complicating matters along this line, however, is that the Brazil and Korea studies, shared a researcher, the relatively well known psychiatrist with a large pubmed autism prevalence footprint, Eric Fombonne. It occurred to me that it might be a fun experiment to see how reliable Mr. Fombonne has been regarding autism prevalence.
[Click on the image to get a bigger view / stupid wordpress template] Note that I have omitted review papers, or papers that had no abstracts, but it doesn’t really help. (How could it?)
All of these findings were wholly or partially authored by the same person. Is there anything more damning for the state of autism prevalence research than this person continues to be considered a source of reliable information?
I used to live with a fun dude in college; he went to engineering school and went on to work at a manufacturing facility near our town. One of the funniest things he told me about engineering was this quote:
Dilution is the solution to pollution!
In other words, if you have a hundred pounds of diethyl-pthylate-poisonate to dispose of, ship in a hundred thousand gallons of water, and start pumping; if you have two hundred pounds to eject, ship in two hundred thousand gallons of water. This is what is happening to the definition of autism, the quirky element, the ‘broad autistic phenotype’ is seeping into these studies. After dozens, or hundreds of prevalence studies we are ultimately left with as many portraits of different entities as envisioned by the researcher and width of spectrum de jour. The upshot of this, however, is that it makes no sense to try to compare these studies.
In the meantime, we are told time and time again that even though our common sense, our memories of childhood, and the repeated lamentations from every person who has worked with children for the last few decades, all of which are warning us that something is different; all of these things are all supposedly subject to an array of biases so strong that we cannot trust them to reach any conclusions. Only through carefully planned, objective analysis can we reach any conclusions on autism incidence. The results of this choreographed investigation looks like this:
Does anyone really think there aren’t some pretty serious biases operating here? If we cannot use common sense to try to reconcile the picture above, what can we use? If trusting common sense is dangerous to valid conclusions, so is trusting this.
If anyone really thought that Korea and Brazil were measuring the same condition, a condition that until very, very recently has been considered lifelong and severely debilitating, the two wildly different findings would be cause for alarm, undeniable evidence of a massive environmental force influencing the development of autism in some populations. But no one thinks this, no one cares, and that is because; no one really believes these studies are measuring the same thing. But admitting this is dangerous to too many, it is the implicit acknowledgement of just how little we understand, how beholden our policies and research prioritizations are guided by the softest of science and scientists, and ultimately, how frequently we’ve been sold a narrative with the scientifically defendable value of a set of monetized South Florida mortgages.
Such is the way of the prevalence hookup, transiently entertaining, but without meaning from week to week. Until we can find a way past this, past reliance on the shifting sands of behavioral assessments that can vary from researcher to researcher (or by the same researcher!), we can perform all of the ‘thorough investigations’ that we can afford and repeat the ‘findings’ that support our meme until we are blue in the face. None of it will mean a goddamned thing, though we may lose a generation of children while we bounce from one set of findings to another, feeling pleased with the ones that make doom seem unlikely, and discarding the ones that should be cause for great alarm.
Hello friends –
I ran into a few abstracts, read a few papers, and tried to get my way through one really dense paper in the past few weeks that got me thinking about this post. It’s all shook up, like pasta primavera in my head, but hopefully something cogent will come out the other end. (?)
Of the metabolic conditions known to be associated with having a child with autism, hypothyroidism is one that I keep on running into by way of the pubmed alert grapevine. By way of example, we have two studies that looked for autoimmune conditions in family members which found hypothyroidism to be one of many autoimmune diseases as a risk factor for autism, including, Familial clustering of autoimmune disorders and evaluation of medical risk factors in autism, and Increased prevalence of familial autoimmunity in probands with pervasive developmental disorders. This shouldn’t be too surprising, we know that, for example, perinatal hypothyroidism is a leading cause of mental retardation, with similar findings for the condition during pregnancy. It turns out, it appears that rates of hypothyroidism are slightly increasing, though at this time, the increases are of relatively small proportions, and as such, may be artifacts unrelated to an actual increase in classically recognized hypothyroidism. In any case, I think it is safe to say that interference with thyroid metabolism is something to be avoided at all costs when possible.
So after having read about that, this paper showed up in my inbox a while ago:
Thyroid hormones have long been known to play important roles in the development and functions of the central nervous system, however, the precise molecular mechanisms that regulate thyroid hormone-responsive gene expression are not well understood. The present study investigated the role of DNA methylaion and histone acetylation in the effects of perinatal hypothyroidism on regulation of reelin and brain-derived neurotrophic factor (BDNF) gene expression in rat hippocampus. The findings indicated that the activities of DNA methyltransferase (DNMT), methylated reelin and BDNF genes were up-regulated, whereas, the activities of histone acetylases (HAT), the levels of global acetylated histone 3 (H3) and global acetylated histone 4 (H4), and acetylated H3, acetylated H4 at reelin promoter and at BDNF gene promoter for exon II were down-regulated in the hippocampus at the developmental stage of the hypothyroid animals. These results suggest that epigenetic modification of chromatin might underlie the mechanisms of hypothyroidism-induced down-regulation of reelin and BDNF gene expression in developmental rat hippocampus
This gets interesting for autism because reelin, and bdnf levels have been found to be decreased in several studies in the autism population, with direct measurements, genetic expression, mouse knockout based models of autism , and genomic alterations all being implicated. There have been some negative genetic studies, but considering that it isn’t always the genes you have, but the genes you use, our other available evidence certainly points to BDNF and reelin involvement with some percentage of children with autism, and the association is such that a reduction in reelin or BDNF is a risk factor for developing autism. It would seem that the paper above might give some insight into the lower level details of the effects of hypothyroidism and subsequent developmental trajectories; modifications of reelin expression; through epigentic mechanisms, no less!. That’s pretty cool!
Then, I got my hands on a review paper that tries to go into detail as to the functional mechanism by which reelin deficiency could contribute to ASD, Neuroendocrine pathways altered in autism. Special role of reelin. It is a review that touches on a variety of ways that reelin contributes to neurodevelopment that have findings in the autism realm, including neuronal targeting and migration during brain formation, interactions with the serotonin and GABA systems, testosterone, and oxytocin. In short, there are plenty of ways that decreased reelin expression can impact development in ways that mirror our some of our observations in autism.
Of the many things that convince me that we are doomed, the proliferation of chemical compounds whose interactions within our bodies we scarcely understand is among them. In my readings on endocrine disruptors, one thing I found that seemed to be worrying lots of researchers was that some classes of these chemicals are capable of interfering with thyroid metabolism, and in some cases interfering with development of cells known to be associated with autism. Terrifyingly enough, since I read those papers, several others have come out, including Polybrominated Diphenylether (PBDE) Flame Retardants and Thyroid Hormone during Pregnancy and Mini-review: polybrominated diphenyl ether (PBDE) flame retardants as potential autism risk factors. At this point, it is important to point out that, as far as I know, there have not been any studies showing that non occupational exposure to PDBEs or other environmental pollutants can lead to classically defined hypothyroidism, at least none that I know of. (?) Be that as it may, I think it is realistic to assume any interference in thyroid metabolism is a bad thing, and while finding people in the outlier regions of hypo (or hyper) thyroidism gives us information on extreme environments, it would take someone with a lot of misplaced faith to assume that we can safely disturb thyroid metabolism just a little bit, and everything will come out in the wash.
I’ve had the argument made to me in the past that environmental pollutant driven increases in autism lacked biological plausible mechanisms; this argument is almost always made within a context of trying to defend the concept of a static rate of autism. While the papers I’ve linked to above do not provide conclusive proof that our changing environment is causing more children to be born with autism, they do provide increasing evidence of a pathway from pollutants to ASD, and indeed, the lack of biological plausibility becomes an increasingly flacid foundation on which to assume that our observations of an increased rate of autism are illusory. Unfortunately, in my opinion, the focus on vaccines has contributed to the mindset that a static rate of autism (or nowadays, maybe a tiny increase), must be protected at all costs, including some ideas on the application of a precautionary principle that seem outright insane to me (or at least, the exact opposite of what I would consider to be a precautionary path).
One thing is for certain, the number of child bearing women in developing countries with measurable concentrations of chemicals known to interferre with thyroid metabolism nears 100% in the industrialized nation as we eat , drink, breathe and bathe in the microscopic remnants of packaging materials, deteriorating carpet fibers, and baby clothes that are made to be fire resistant. This is an environment unambiguously different than that encountered by any other generation of infants in the history of mankind. To believe that we can modify our environment so drastically without having an impact seems incredibly naive to me, or on some days, just plain old stupid.
Hello friends –
One of my biggest problems with the Fairytale of a Static Rate of Autism is that we need to ignore the reckless environmental engineering that our species has engaged upon in the past few decades. My concerns lay within the inherent, difficult to underestimate stupidity of our actions, wherein our perceived understanding of the impact our actions are far less pronounced than the actual impact of our actions. For the telescopic illustration of this worldview, go back any number of years where X is greater than thirty, and see if the expectations and predictions of those times match up well with what has actually occurred. While our achievements are great and wondrous, it is at our great peril we come to believe we understand sufficiently our actions to predict their outcomes.
In any case, a progenitor of great concern, or indeed, impending doom, to my mind, is the increasing environmental ubiquity of a variety of industrial chemicals that have the potential to interfere with biological processes in difficult to predict ways, endocrine disruptors. Although there are no doubt naturally occurring substances with similar properties, for purposes of this discussion, lets assume that my concern (and yours), should be with chemicals that were manufactured by man that have molecular structures so similar to naturally occurring molecules that they can interfere with low level metabolic processes in a myriad of ways that are difficult to understand without very detailed analysis. Unfortunately, subtle effects during critical developmental time frames can propagate outward into long lasting, not so subtle effects. Doubling down, we are largely reliant on corporations largely responsible for the next quarter share price to ascertain if subtle effects are happening or not.
To start the horror show, considers Bisphenol-A , a plasticizer used in pretty much everything, but especially in things like the tupperware you put in the microwave, bottles you give your baby, canned goods, or anything else you buy in the grocery that has a shelf life. This particular mish mash of atoms tends to break down into something that is chemically very similar to estrogen, so similar, in fact, that the keys and locks of the cellular machinery of your metabolism can get confused. It turns out, when this happens, we start seeing disturbing associations between circulating levels of BPA and a variety of conditions you’d rather not have, including heart disease and diabetes. On top of tons of animal models of BPA exposure and metabolic dysfunction, immune changes, and we now have several human studies wherein urinary levels of these chemicals is associated with adverse outcomes. And those are just the direct effects!
It would seem that BPA can have epigenetic effects too, wherein it can modulate which genes get expressed, and that’s a lot like getting a whole different set of genes. For a fascinating (and terrifying) ride, I’d recommend that anyone take a look at this slide show from NOVA science now that goes over some of the effects of BPA to a prenatal environment. I double dog dare anyone who doesn’t think we are doomed to watch this episode.
That was the good news.
The uncontested facts on the ground are that, as a species, we are being exposed to BPA in ways that no previous generations of humans, or mammals, vertebrates, invertebrates, or living thing has ever been exposed to. There is no way we are clever enough to understand the ramifications of this, and yet, we have up and distributed BPA in measurable and non trivial concentrations in every human body touched by modern convenience.
The Scary Chemicals stories will involve research on a variety of chemicals identified as endocrine disruptors with known or suspected properties that would allow them to interact with development in ways meaningful to autism research. BPA is one. There are many, many others.
Hello friends –
This post really ought to be Chapter 1, but since I wrote the other post first, and sort of liked the title, so we’ll just pretend; these posts are all about make believe in any case, right?
There is only one valid reason not to vigorously pursue environmental causes of autism; you need to believe that our observation of an increased rate of autism, one hundred percent of it, is an artifact of the four horsemen of the imaginary increase:
- Diagnostic Substitution
- Greater Awareness
- Increased Accessibility to Diagnosis
- Widening of Diagnostic Criteria
Lets start off with a couple of honest admissions and the reason they don’t make a whit of difference if our goal is to expose the notion of a static rate of autism as a fairytale, and a dangerous one at that.
- I have read very few papers regarding prevalence fully. In fact, I can’t think of the title of a single one. In the context of a precautionary principle, however, the methods and discussion for this type of study don’t really matter much; because the brush strokes used to craft the results are so necessarily broad and imprecise that they are admitted as meaningless even by people who believe in the fairytale. Think about it. The only way we have a static rate of autism is if all of our previous studies utilized methods of such poor quality that they missed ##-## per 100,000 cases of autism, where you get to replace ##-## with any set of numbers lower than 100 as you move backwards in time. The conclusions in our previous prevalence studies are so discordant over time that the flaws in their methodology are the super strings of the fairytale; responsible for all of our observations of increased autism rates while having natural physical properties that render them impossible to elucidate on completely. Given that even the proponents of the fairytale don’t give the methods of previous studies any currency, why should anyone?
- I cannot provide meaningful estimates on what percentage of the observed increase in rates is real versus artifact. Again, however, in the prism of a precautionary principle, it doesn’t matter, because any amount of real increase is alarming, and the only possible unalarming possibility is a zero percent increase. Here is a little thought exercise to illustrate this; imagine you are on a debate team and the topic is; “Autism rates have risen by X percent, health crisis or not?” and your team has drawn the ‘not a crisis’ side. Insert any number greater than zero for X, and then try to construct debate points to make this argument to a crowd of skeptics. This argument is implied whenever the fairytale is invoked, sometimes with the assertion that any real increase is “minor”, but one surefire way to get a storyteller to dissolve from a discussion is to try to get a value more concrete than “minor” for X. Autism is a disability, and while there are arguments to be made that it is also a ‘difference’, it isn’t a difference like having red hair or being left handed anymore than dyslexia is a different way of reading; any true increase has broad implications for us all.
- I have no doubt that the four factors listed above are, indeed, responsible to one degree or another towards what we are observing in autism rates. Unfortunately, unless we are able to explain our ever rising rates of autism completely with these explanations, we still must contend with ramifications of a true increase.
Even with the above caveats, a compelling case can be made that what we are observing is comprised of an actual increase in behaviors consistent with an autism diagnosis, and the argument that autism rates are static is long on faith and very low on the lifeblood of science; reliable data.