Ever since I somehow stumbled into a niche in the blogosphere where I seem to be one of a handful of go-to bloggers for issues having to do with vaccines and the anti-vaccine movement, like Spider-Man I realize that with great power comes great responsibility.
Wait a minute. That beginning was too pompous and pretentious even for me. I know it’s hard to believe, but even Orac has limits when it comes to pretentiousness.
Orac-ian pomposity aside, there are indeed certain topics that I can’t resist. Whether it’s because they intensely interest me or my being an aforementioned “go-to” blogger compels me out of a sense of duty to take them on, take them on I must. Of course, what’s good about such topics is that they generally serve me up custom-made blog material and guarantee that, for a day at least, I have no trouble finding things to write about. Thankfully (or unfortunately–I can’t make up my mind), the anti-vaccine loons at Age of Autism have provided me with perfect material for a Friday in the form of their promotion of a brand, spanking new monkey study that purports to find that vaccines cause autism (or at least disturbing brain changes) in Macaque monkeys. Sadly, but not unexpectedly, this study is not in any sense brand or new, although it may well be spanking. Certainly it deserves a sound spanking, and that’s what it’s going to get right now.
“New study shows vaccines cause brain changes found in autism!” proclaim Dan “Where Are The Autistic Amish?” Olmsted and Mark “Not A Doctor, Not A Scientist” Blaxill, and the ravening hordes of anti-vaccine loons go wild. Yep, that’s what I’m talking about. Unfortunately.
Yes, the other day Laura Hewitson published as lead author a study in a journal that I had never heard of before (Acta Neurobiologiae Experimentalis) entitled Influence of pediatric vaccines on amygdala growth and opioid ligand binding in rhesus macaque infants: A pilot study. Think of it as Monkey Business in Autism Research, Take 3. But before I go into this study, perhaps it’s a good time to recap Monkey Business in Autism Research, Take 1 and Take 2. Note that this research is the same research that was published in NeuroToxicology last fall and then withdrawn in February in the wake of Wakefield’s disgrace due to his having had his medical license taken away by the General Medical Council in the U.K.
Basically, this “research,” first reported in an abstract at IMFAR back in 2008, is crap science through and through. It suffers from so many methodological flaws that I still marvel that it managed to get through any sort of peer review, much less IACUC review, and its lead investigator has a massive conflict of interest. I once complained about the “studies” that came from these experiments as being what’s known as the “minimal publishable unit” (a.k.a. MPU). In other words, Wakefield and his cronies appeared to be doing one monkey experiment and then chopping it up into as many individual papers as they can. From that, there were the three abstracts at IMFAR, the NeuroToxicology paper–and now this latest atrocity against science.
First, there’s one thing that stood out–nay, leapt out–at me as I read this paper. Do you see it? It’s there in the abstract and it’s there in the paper itself. Andrew Wakefield’s name is not on the paper. In fact, in the Acknowledgments section, we find this curious sentence:
Special thanks to Dr. Andrew Wakefield for assistance with study design and for critical review of this manuscript; and to Troy and Charlie Ball and Robert Sawyer.
Can it be? Andrew Wakefield relegated to a mere “special thanks to” notice tacked onto the end of the mansucript? Remember, Wakefield’s name was featured prominently on the previous incarnations of this study. His fingerprints are all over it. By any rights he should be the senior author on the paper, but he isn’t. I can only guess it’s that the reason is that his name and reputation are so toxic that the appearance of the Wakefield moniker on a submitted manuscript would guarantee that it won’t be accepted even in an apparently bottom-feeding journal like Acta Neurobiologiae Experimentalis. Actually, any journal that would accept a journal article this bad by Wakefield’s protÃ©gÃ©, is almost by definition a bottom-feeding journal, but if you have any doubts, check out the rest of the issue, which contains not one but two articles by those masters of autism quackery, Mark and David Geier, originators of the Lupron protocol, not to mention an article by Hitlan and DeSoto. Truly, it’s a cornucopia of bad autism science! Perhaps, as Kev points out, it has something to do with the person who chose the theme of this particular issue of Acta Neurobiologiae Experimentalis, Professor Dorota Majewska. Although I don’t recall having mentioned it before, someone named Professor Majewska signed the original We Support Andy Wakefield petition that I had some fun with a while back.
Coincidence? I think not.
Another thing I noticed right away is another odd omission. There is no conflict of interest statement, even though there most definitely should be. As mentioned before, Hewitson has an autistic child who is part of the Autism Omnibus case. This sort of research, if it had been published earlier, could have been used to bolster the complainants’ case. Having been burned two years ago with criticism for not having reported her COI, Hewitson did report it in the 2009 withdrawn NeuroToxicology paper. Now she isn’t reporting it. I wonder why.
Actually, no I don’t.
In any case, on to the present study, which is clearly an offshoot of this earlier work. This is what was found:
Abstract. This longitudinal, case-control pilot study examined amygdala growth in rhesus macaque infants receiving the complete US childhood vaccine schedule (1994-1999). Longitudinal structural and functional neuroimaging was undertaken to examine central effects of the vaccine regimen on the developing brain. Vaccine-exposed and saline-injected control infants underwent MRI and PET imaging at approximately 4 and 6 months of age, representing two specific timeframes within the vaccination schedule. Volumetric analyses showed that exposed animals did not undergo the maturational changes over time in amygdala volume that was observed in unexposed animals. After controlling for left amygdala volume, the binding of the opioid antagonist [11C]diprenorphine (DPN) in exposed animals remained relatively constant over time, compared with unexposed animals, in which a significant decrease in [11C]DPN binding occurred. These results suggest that maturational changes in amygdala volume and the binding capacity of [11C]DPN in the amygdala was significantly altered in infant macaques receiving the vaccine schedule. The macaque infant is a relevant animal model in which to investigate specific environmental exposures and structural/functional neuroimaging during neurodevelopment.
Interesting. Hewitson’s finding claims that animals vaccinated with thimerosal-containing vaccines underwent increases in the size of the amygdala relative to control animals. As always, though, the devil is in the details, and it’s necessary to read the experimental methodology. Note that in this study, as in the previous iterations of this misbegotten study, there was a large mismatch in number between the control group and the experimental group, with four being given saline controls and twelve being given a vaccine “schedule” designed to mimic the vaccine schedule given to children in the U.S. in the 1990s. Hilariously, because all these vaccines are thimerosal-free, Hewitson had to add thimerosal to the vaccines to produce its replication of the vaccine schedule from the 1990s. Of course, because Macaque monkeys mature faster than humans, they received in one year what humans receive in four years.
During this whole period, the investigators then performed MRI and functional MRI, as well as positron emission tomography (PET) scans on the monkeys, which is why I say right here: Don’t get me started on how incredibly unethical Hewitson and Wakefield’s treatment of these poor monkeys. Remember, these monkeys have to be anesthetized every time they undergo a test, and they’re being jabbed with various vaccines or saline solutions all in the service of a highly improbable hypothesis that has been tested time and time again in humans through large epidemiological studies. These aren’t just mice or rats we’re talking about, either. They’re primates and highly intelligent. In fact, I would hesitate even to treat mice this way, and I know our IACUC at my university frowns on experiments that require multiple anesthesias and multiple procedures even on mice.
More interesting is something I found when I read the methods section more closely:
A complete set of MRI data at both T1 and T2 were obtained from 9 exposed and 2 unexposed animals.
And then there was this:
A complete set of PET data at both T1 and T2 were obtained from 9 exposed and 2 unexposed animals.
So let’s see. There were originally 12 exposed monkeys and four unexposed monkeys. That’s bad enough in that the number of monkeys in the control group was so small that it would take a large difference between the vaccinated group and unvaccinated group to produce anything resembling statistical significance. With only two animals in the control group, the situation is even worse. With such a control group, it would be damned near impossible to achieve a result that is statistically significant, and doing statistical analysis on such a data set is an exercise in futility. Worse, no explanation is given for why the three monkeys from the vaccinated group and one monkey from the unvaccinated group weren’t included in the analysis. (One of the monkeys in the unvaccinated control group was apparently excluded for the protocol not being followed.) That’s a rather glaring omission. A glaring omission indeed. If I were reviewing this paper, I would have demanded that the authors explain to me why they left out those monkeys and put a passage in the manuscript describing their rationale. Good thing for Hewitson I wasn’t a reviewer.
There’s also a disconnect betweent he abstract and what is actually reported in the paper. Let’s reiterate part of what the abstract says:
Vaccine-exposed and saline-injected control infants underwent MRI and PET imaging at approximately 4 and 6 months of age, representing two specific timeframes within the vaccination schedule.
Elswhere in the paper, the authors state:
For the exposed group there was a nonstatistically significant increase in right amygdala volume over time (P=0.16; Table IIa). For the unexposed group there was a significant drop in right amygdala volume over time (P<0.0001; Table IIa).
As Sullivan noted, that’s right: The authors observed a significant decrease in right amygdala volume in the control animals between four and six months of age. In fact, look at the figure that Sullivan relabeled from the paper to make it clearer. This is not a slight degree of shrinkage, either. It’s nearly a 30% shrinkage. Come to think of it, I hope Sullivan won’t mind, but I’m including a thumbnail of his graph with a link to it below:
Also, as Sullivan points out, in infant monkeys, the amygdala doesn’t shrink. They grow until they reach full size at around 24 months. Yet in Hewitson’s experiments, the amygdala shrank nearly 30% in just two months between four and six months of age, while the sizes of the amygdalas in the vaccinated monkeys appeared to be increasing in size at a slow rate consistent with normal monkeys. Based on such thin gruel, Hewitson tries to argue that the increase in amygdala corresponds to an increase in whole brain size consistent with what has been reported in children with ASD. Yes, that’s the entire argument and those are the purported findings of the paper, and it’s all based on only 11 monkeys.
So what is the likely cause of this finding? Does this mean that saline injections cause the brain to shrink? Of course not. What almost certainly happened is that the control group was so small that by a random fluke of chance Hewitson happened to get two monkeys for whom the average brain volume decreased. This is not unusual or implausible; there’s a lot of variation in brain size, which is why larger numbers are needed to produce any results that can be believed. An N of 2 just won’t cut it. It’s not even clear that an N of 9 would do it either. Certainly I saw no power analyses worthy of the name in the statistics section, and I also saw a whole lot of “not statistically significant” results.
There’s one final observation. Two years ago at IMFAR, Wakefield and Hewitson presented an abstract that was clearly the precursor to this latest paper. At the time the anti-vaccine loons at AoA were kind enough to post the entire text of the abstracts. So let’s take a look:
Pediatric Vaccines Influence Primate Behavior, and Amygdala Growth and Opioid Ligand Binding Friday, May 16, 2008: IMFAR
L. Hewitson , Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA B. Lopresti , Radiology, University of Pittsburgh, Pittsburgh, PA C. Stott, Thoughtful House Center for Children, Austin, TX J. Tomko , Pittsburgh Development Center, University of Pittsburgh, Pittsburgh, PA L. Houser , Pittsburgh Development Center, University of Pittsburgh, Pittsburgh, PA E. Klein , Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, PA C. Castro , Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA G. Sackett , Psychology, Washington National Primate Research Center, Seattle, WA S. Gupta , Medicine, Pathology & Laboratory Medicine, University of California – Irvine, Irvine, CA D. Atwood , Chemistry, University of Kentucky, Lexington, KY L. Blue , Chemistry, University of Kentucky, Lexington, KY E. R. White , Chemistry, University of Kentucky, Lexington, KY A. Wakefield , Thoughtful House Center for Children, Austin, TX
Background: Macaques are commonly used in pre-clinical vaccine safety testing, but the combined childhood vaccine regimen, rather than individual vaccines, has not been studied. Childhood vaccines are a possible causal factor in autism, and abnormal behaviors and anomalous amygdala growth are potentially inter-related features of this condition.
Objectives: The objective of this study was to compare early infant cognition and behavior with amygdala size and opioid binding in rhesus macaques receiving the recommended childhood vaccines (1994-1999), the majority of which contained the bactericidal preservative ethylmercurithiosalicylic acid (thimerosal).
Methods: Macaques were administered the recommended infant vaccines, adjusted for age and thimerosal dose (exposed; N=13), or saline (unexposed; N=3). Primate development, cognition and social behavior were assessed for both vaccinated and unvaccinated infants using standardized tests developed at the Washington National Primate Research Center. Amygdala growth and binding were measured serially by MRI and by the binding of the non-selective opioid antagonist [11C]diprenorphine, measured by PET, respectively, before (T1) and after (T2) the administration of the measles-mumps-rubella vaccine (MMR).
Results: Compared with unexposed animals, significant neurodevelopmental deficits were evident for exposed animals in survival reflexes, tests of color discrimination and reversal, and learning sets. Differences in behaviors were observed between exposed and unexposed animals and within the exposed group before and after MMR vaccination. Compared with unexposed animals, exposed animals showed attenuation of amygdala growth and differences in the amygdala binding of [11C]diprenorphine. Interaction models identified significant associations between specific aberrant social and non-social behaviors, isotope binding, and vaccine exposure.
Conclusions: This animal model, which examines for the first time, behavioral, functional, and neuromorphometric consequences of the childhood vaccine regimen, mimics certain neurological abnormalities of autism. The findings raise important safety issues while providing a potential model for examining aspects of causation and disease pathogenesis in acquired disorders of behavior and development.
Note that we appear to have had a mass exodus of authors from this study Note also the emphasized sentence.
That’s right. Back then Hewitson was reporting that the amygdalas of the infant monkeys were not growing normally in the vaccinated group. There were also 13 monkeys in the vaccinated group and three in the unvaccinated group, truly the incredibly morphing expermental groups. It looks to me as though some hypothesis rearrangement intervened here. Apparently between 2008 and 2010, someone read some research suggesting larger brain sizes were characteristic of autism and ASD. Either that, or I can’t help but ask Hewitson: How could this have happened? Were you incompetent then analyzing your data or are you incompetent now? OK, I admit it. It’s a trick question. The two aren’t mutually exclusive, and Hewitson appears to have been incompetent both then and now, in my not-so-respectfully insolent opinion. The study didn’t have enough monkeys, particularly in the control group, to come to any conclusion worth having any confidence in whatsoever.
What a horrific waste of primates!
Naturally, none of this stops Wakefield’s cheerleaders over at the anti-vaccine crank blog Age of Autism from promoting this study to the hilt, even going so far as to cite Wakefield’s discredited “monkey business” study as though it showed anything other than no real difference between the groups and were a different study altogether, rather than just another appendage of the same incompetent experiment. In the comments we’re treated to examples of conspiracy mongering so hilarious that I laughed out loud at a couple of them, in particular this one by Jeff C.:
…this will be dismissed by the medical establishment as a study conducted by known “anti-vaccine nuts” published in some “third-rate, foreign journal”. They’ll say, “Why isn’t it published in a reputable, mainstream journal? How do we know the peer review was adequate?”
Of course, they control the “mainstream” journals, they control peer review, and would never let a study like this see the light of day. The system is rigged, and they’ll use that to discredit or stifle any study not to their liking.
The only way to break the dam is to keep studies like this coming. In the meantime, we need to get the word out on this one.
Actually, were it not for the abuse of primates, a part of me would hope the anti-vaccine movement keeps studies like this coming. Nothing destroys their scientific reputation faster than such mind-meltingly awful science. It’s so bad that each study like this can only guarantee further scientific marginalization of these cranks. It also provides excellent blog fodder, although too much risks frying my fragile eggshell mind.
Too bad it’s such a crime that so many monkeys had to give their lives in the service of such bad science. Blog fodder and discrediting the anti-vaccine movement aren’t worth the loss of primate life.
More reading on this terrible study:
- Terrible Anti-Vaccine Study, Terrible Reporting (crossposted to Science-Based Medicine)
- The genie is out of the bottle: vaccines cause autism
- The genie is out of the bottle. Part II – more genies, more bottles
Geez, the comments are getting worse:
The increased head size is likely caused by heavy metal interference with apoptosis (programmed cell death) which is the brain’s way of modelling itself into an optimum configuration. My older autistic son had a remarkably large head as a toddler which is now a more normal size as a teenager.
Let’s see, he’s mastered the science-y sounding jargon but clearly has no clue what it means. Truly, here we see an example of a little knowledge being a dangerous thing.
If you want to know how bad this study is, consider the fact that homeopaths like it.