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Safeminds comments on the latest thimerosal-autism study

21 Sep

SafeMinds is an organization which has long promoted the idea that thimerosal caused an autism epidemic. They may be the single greatest force that got the idea into the public’s eye, and got research funding focused on looking at the question.

SafeMinds has shown themselves to be very resistant to the very research they called for. Studies which show a lack of association between thimerosal containing vaccines (TCV’s) and autism are always rejected by SafeMinds. They are not alone in this, groups such as Generation Rescue and the National Autism Association (NAA) have also refused to accept the science.

So it was with no surprise that I read that SafeMinds had issued a statement against the study. The statement starts by pointing out that the study was funded and performed by those with conflicts–the CDC, Abt (an organization which does contract research for groups including the CDC), and HMO’s “which receive substantial funding from vaccine manufacturers to conduct vaccine licensing research”.

If we can’t use the HMO’s to work on such project, that sort of takes away the VSD as a tool. It certainly takes away the opportunity to do anything more than passive surveillance of the VSD data. One of the strengths of the Price study was the effort to do more than just review the medical charts. They worked with the children, both cases and controls, to verify that the autism counts were accurate. I bring this up because groups like SafeMinds frequently request access to VSD data.

SafeMinds also discusses the study methodology:

The study sample did not allow an examination of an exposed versus an unexposed group, or even a high versus a low exposed group, but rather the study mostly examined the effect of timing of exposure on autism rates.

There is much wrong with the above statement. Let’s start with where they are close to correct. The study sample did not allow for a direct comparison (with good statistics) of exposed vs. unexposed. This is true. This is because there are few unexposed kids (unexposed=no thimerosal exposure in this study. Unexposed does not mean no vaccines). If you look at exhibit 9.1.4 from the technical reports by Abt associates (the detailed reports on the study), you will see about 20-30 “unexposed” children. I.e. children with no thimerosal exposure. Of those, about 3-4 (out of 1,000) had no HiB, HepB or DTP vaccine vaccine at all (MMR isn’t listed as it is not a source of thimerosal). This is in line with estimates by the CDC of how many children are unvaccinated (typically about 0.4%). (as an aside–this points out how difficult it would be to do a good study of vaccinated vs. unvaccinated children using the VSD. Seriously, with 99.6% of kids receiving at least one vaccine, you would need a huge number of kids to get the number of unvaccinated needed for good statistics).

Here is that exhibit, with the no-exposure kids circled. (click to enlarge)

It would appear to this reader that the issue of unexposed vs. exposed isn’t so much one of “study design” as the limitations of the VSD itself. There just aren’t that many autistic kids to make a good statistical comparison of unexposed vs. exposed populations.

And, it should be noted, an unexposed vs. exposed comparison wasn’t the purpose of this study. One big question posed by SafeMinds and later picked up by groups such as Generation Rescue was simple: did the increase in thimerosal exposure from vaccines in the 1990’s result in an “epidemic” of autism? This is the question this study addressed.

I am at a loss as to why SafeMinds wrote this: “….or even a high versus a low exposed group, but rather the study mostly examined the effect of timing of exposure on autism rates”. Contrary to SafeMinds’ assertion, there is a large variation on thimerosal exposure in the study subjects. One of the surprising facts from this study was the number of children receiving thimerosal-free vaccines. This, together with variations in the number of vaccines administered, led to a much larger distribution in thimerosal exposures than one would expect based on the vaccine schedule alone.

Thus, the study was not on “timing” at all. It was, as advertised, on variation of exposure of thimerosal. The question is (at least to me), does the range of exposure amount to significant number of kids having “low” levels of exposure by SafeMinds’ definition?

The answer, it turns out, is yes.

Safeminds has the following statement on their website:

[Autism] remained rare (1 in 10,000) until the rapid escalation of vaccines beginning in the late 1980’s (from 10 shots of 7 antigens in 1983 to 36 shots of 15 antigens). Vaccines are a likely candidate to explain some, if not most of the rise in autism cases and possibly other chronic childhood disorders linked to immune system malfunction.

In one of the seminal papers on the thimerosal was co-written by SafeMinds founder Lyn Redwood Autism: a novel form of mercury
poisoning. In it, the authors state:

The discovery and rise in prevalence of ASD mirrors the introduction and spread of TMS in vaccines. Autism was first described in 1943 among children born in the 1930s (123). Thimerosal was first introduced into vaccines in the 1930s (7). In studies conducted prior to 1970, autism prevalence was estimated, at 1 in 2000; in studies from 1970 to 1990 it averaged 1 in 1000 (124). This was a period of increased vaccination rates of the TMS containing DPT vaccines among children in the developed world. In the early 1990s, the prevalence of autism was found to be 1 in 500 (125), and in 2000 the CDC found 1 in 150 children affected in one community, which was consistent with reports from other areas in the country (126). In the late 1980s and early 1990s, two new TMS vaccines, the HIB and Hepatitis B, were added to the recommended schedule (7).

I know I am spending a lot of time on this point, but it is important. The idea that there is a dose-response relationship between thimerosal and the presumed risk of autism is fundamental to the arguments made by groups like SafeMinds.

A sister organization to SafeMinds, Generation Rescue, says the same thing. In their take, “This is the schedule from 1983. If it worked for kids then, why doesn’t it work for kids now?”. Generation Rescue leader and spokesperson Jenny McCarthy wrote in her book, Healing and Preventing Autism: A Complete Guide, “In 1983, we had 10 shots on the vaccine schedule and autism was one in 10,000. Today there are 36 given and autism is nearing one in 100”. I.e. if we go back to the 1983 vaccine schedule, autism rates should drop to 1 in 10,000.

The 1983 schedule, as graphically presented in expensive full page newspaper ads by Generation Rescue, included 4 DPT shots (yes, the old whole cell pertussis vaccine). Each of those shots included 25 micrograms of mercury.

It strikes this reader that the thimerosal exposure from 4 DPT shots, the amount in the 1983 schedule that supposedly only resulted in 1 in 10,000 kids having autism, should be a “low” exposure amount. If groups are going to point to 1983 as a safer schedule and point to the increases in thimerosal exposure in the 1990’s as the major sign of the “epidemic”, we should be able to take their word that the levels in 1983 were somehow safer.

Let’s look at that figure from the Price study again, shall we? I will highlight how many kids have “low exposure” (i.e. comparable to the 1983 vaccine schedule) to thimerosal. Again, click to enlarge if you wish.

By my eye, something approaching 50% of the kids in the study received the thimerosal exposure of the 1983 schedule. Certainly more than 25%. Those highlighted in red have the same thimerosal exposure as kids did in 1983, so they should have the same autism prevalence that SafeMinds and Generation Rescue claim for that time period: 1 in 10,000.

If that group has a prevalence of 1 in 10,000–or even anything significantly lower than the prevalence of those with higher thimerosal exposure– this study would have found it.

In other words, a thimerosal-induced epidemic of autism didn’t happen. Even using the logic that SafeMinds used to hypothesize it in the first place:that, somehow, the thimerosal exposures in 1983 resulted in a low autism prevalence.

Yes, this is far from rigorous. But, so is the logic that claims that increased thimerosal exposure led to an autism epidemic.

If we read further into the SafeMinds response, we see some of the confusion:

The study sample did not allow an examination of an exposed versus an unexposed group, or even a high versus a low exposed group, but rather the study mostly examined the effect of timing of exposure on autism rates. There were virtually no subjects who were unvaccinated and few who were truly less vaccinated; rather, the low exposed group was mostly just late relative to the higher exposed group, ie, those vaccinating on time.

SafeMinds seems to be assuming this is a study on the number of vaccines, not the amount of thimerosal. They also don’t appear to have read the study thoroughly enough to note that, yes, there is a large fraction who were “less vaccinated” and, more importantly to this study, a large fraction who had lower thimerosal exposures. As noted above, the low thimerosal exposures result from the fact that many of the children received thimerosal free vaccines.

It is unfortunate that SafeMinds (and other groups like them) can not adapt to science as it comes out. Science which clearly shows that many of their hypotheses were wrong.

The Respectful Insolence blog also discusses some of the failings of the SafeMinds response.

Hannah Poling and the Pediatrics thimerosal study: two “big” stories with little press response

18 Sep

Two stories which are “big” news in some segments of the online autism community are the settlement amount for Hannah Poling and the recent study showing no link between autism and thimerosal in vaccines. While these have caused a fair amount of discussion on blogs (like this one), they didn’t generate that much press coverage.

We broke the Hannah Poling award story here on LeftBrainRightBrain on September 3. The story was ignored, even by such pro autism-as-vaccine-injury blogs as the Age of Autism until September 9th, when Sharyl Attkisson (who has some connection to the people at the Age of Autism blog) wrote about it for CBS.

There are a couple of dozen entries in Google News on Hannah Poling. Few major outlets. One that did carry it is the Atlanta Journal Constitution, the home town newspaper for the Poling family. In Settlement reached in autism-vaccine case the AJC quoted Dr. John Shoffner:

Dr. John Shoffner, a neurologist and national expert who has conducted research on autism and its causes, said researchers have found no link between vaccines and autism. And he said he strongly favors vaccination.

“The preponderance of data shows that vaccines are important and safe for children to prevent preventable and sometimes life-threatening infectious diseases,” Shoffner said. “I certainly am in favor and support the CDC’s as well as the American Academy of Pediatrics’ recommendation of vaccination.”

Shoffner is a co-author of a journal article that describes Poling’s case without naming her.

Edited to add: I forgot to include this quote from the Atlanta Journal Constitution:

“It’s critical to remember that the government has never compensated, nor has it ever been ordered to compensate, any case based on a determination that autism was actually caused by vaccines,” said Martin Kramer, communications director for the Health Resources and Services Administration. The National Vaccine Injury Compensation Program is part of the administration. The U.S. Court of Federal Claims decides who will be paid damages for injuries that result from vaccines, under a 1988 law that created a program.

Another so-called “big” story from the last few weeks is the study on autism and thimerosal in Pediatrics, Prenatal and Infant Exposure to Thimerosal From Vaccines and Immunoglobulins and Risk of Autism. Sometimes when an important paper comes out (that I am aware of) I watch Google News as the embargo is lifted. I did so with this paper. Nothing happened. OK, I think Disability Scoop had a story out right at midnight (this one, if I recall correctly). Heck, it wasn’t until Friday that the CDC added the study to their website (it isn’t mentioned on the main cdc.gov webpage). Even SafeMinds (who are, in cases like this SafeBet–as in, it is a safe bet they will put out a critique of the paper) didn’t respond for days.

Sure, I was interested. And, yes, these stories sparked some of the most active conversations on this blog in a while. But I am still left with the basic conclusion: the general public has already absorbed these stories. The government conceded the Hannah Poling case 2 years ago. It isn’t new. The idea that mercury in vaccines cause autism–no longer part of the front line public discussion.

I’m not the only one to make this comment. The Washington Post had this to say four days after the paper was made public:

But when the journal Pediatrics published on Monday a study that found no increased risk of autism among more than 1,000 babies who’d been exposed prenatally or in the first 20 months of life to ethylmercury from vaccines, it was met with a general shrug. Neither The Washington Post nor The New York Times even reported on it, though the Los Angeles Times did, in its Booster Shots blog.

Sure, these stories will never completely go away. The vaccine/autism story will never go completely away. But the heyday is over.

Further results from the thimerosal-autism study

14 Sep

The recent study on thimerosal and autism was extensive. Much data and many results were included in two technical reports (nearly 400 pages total, volume 1 and volume 2). I haven’t had the time to read them thoroughly yet, but I did catch some interesting pieces of information.

The authors give the ASD prevalence (cases/1000) as a function of HMO and year of birth:

This is pretty flat. No huge increase seen over that 6 year time span. No evidence for an “epidemic”. The prevalence is about 1.1%. This is consistent with the current value quoted by the CDC.

There are remarkably a big variation by parents educational status (63% kids born to mothers who graduated from college). However, since the researchers are working with kids who are enrolled in an HMO, it seems likely this is due to some bias. I.e. the HMO participants could be better educated (and higher income) than the average.

There are indications that increasing parental age is related to increased autism risk. 36% of mothers were in the 30-34 age bracket, 35% were in the 35+ age bracket. So, about 70% of mothers were over 30 years of age. They list father’s age with different brackets, but 79% were 30 years old or older at the time of birth of their child. Again, could be some bias due to HMO membership, but a large fraction of the parents were older.

Some children (both ASD and controls) received no vaccines. Many received vaccines but no thimerosal–i.e. all their vaccines were thimerosal free.

The use of prenatal vitamins is given as having an increased risk of autism, but the odds ratio is not given.

Being a first-born or second-born child has a significant increased risk for autism (hazard ratios of about 1.6). They may discuss this, but I don’t know right now how much of this is due to parents of autistic kids deciding not to have larger families.

One of the stranger results–there is an increased risk of autism when mothers were using prenatal vitamins with folic acid. The hazard ratio was 2.3 with a p value of 0.0176

Pica and childhood lead exposures had very high hazard ratios: 3.7. This is a good case where it is worth asking if this is causal–does pica cause autism or, as is more likely, does autism cause pica and, with it, higher lead exposures.

Poverty was slightly protective for autism (hazard ratio of 0.92). Again, one has to question if this is real or whether poverty just results in a greater likelihood that a child’s autism will be misdiagnosed.

The authors list coexisting conditions for the autistic, ASD and control children:

Epilepsy is much higher at about 5%, compared to 1.6% for controls. Reports of the prevalence of epilepsy amongst autistics are often much higher, though.

Developmental delay (by parent report) is at about 18% for autistics, compared to about 0.66% in controls.

Gi disorder prevalence is about 2% amongst autistics. It is the same (or slightly higher) for controls. This is very interesting given the anecdotal reports of a high prevalence of GI disorders amongst autistics. I suspect this will form some of the complaints about this study–some will say they aren’t looking at the correct population and that a specific study on autism/regression/GI complaints needs to be done.

Cases (those with ASD) were more likely to get thimerosal free HepB and HIB vaccines.

Infants in this study do not get flu vaccines (near zero). Unless that habit has changed dramatically in the past few years–and that most doctors are giving infants flu vaccines with thimerosal–flu vaccines are not likely to be a reason for the continued climb in autism prevalence.

There is a lot more information there. If/when I get the chance to give the reports a more thorough read I’ll post what I find.

Questions and answers with the thimerosal-autism study author

13 Sep

It is a safe bet that there would be a lot of questions arising from the latest study, which shows no link between thimerosal exposure and autism. I thought there would be some interviews in the press covering most of the obvious questions, so I decided to ask some questions of my own of the study’s lead author, Cristofer Price of Abt associates.

I was very interested in the more complete discussion in their Techical Reports and data. I was also interested in how these results might apply to the idea that there are “too many” vaccines given “too soon”. Mostly I was interested in why this study took so long to get published give the CDC’s statements after the Thompson study of 2007–statements which indicated that this follow-on study should be available within about a year or so.

Below is the exchange:

First: you cite two Abt reports from 2009 on the subject:

Price C, Robertson A, Goodson B. Thimerosal
and Autism. Technical report. Vol I. Bethesda,
MD: Abt Associates Inc; 2009

I can’t find them on your site at this time. Are they there or will they be made available when the embargo is lifted?

[Response: The tech reports will be up on the CDC and Abt web sites on Monday. ]

Will the data be made available as was done with the Thomson(2007) study? If so, how would one access it?

[Response: Yes, the process for obtaining the data will be very much like the process that was in place for the Thompson(2007) study. Instructions for how to access the data and a data use agreement, etc. will be up on the CDC web site on Monday. The terms specified in the data use agreement are similar to those from the prior study. ]

As to the paper, I see that the results are the same for autism with and without regression. Are there any other issues of severity which were checked (e.g. level of intellectual disability, seizures) which were also monitored?

[Response: We did do a sub-analysis where AD cases with low cognitive functioning were excluded (see technical report on Monday for full details and results) Analysis of the subgroup of AD cases where children with low cognitive functioning were excluded was motivated by the following concern. Because children who are non-responsive during the assessment process are more difficult to assess, it can sometimes be difficult to determine whether children with severe developmental delay actually have autistic disorder. If the imprecision of the assessment process for such children resulted in inclusion of children without AD in the AD group, then we would expect that the estimate of the relationship of exposure to AD risk could be attenuated. Therefore, an outcome category for AD with low cognitive functioning excluded was created and its relationship to exposure was estimated. The results for this subgroup were very similar to those for the overall analysis.]

There are children (both case and control) who have 0 mercury exposure from vaccines in all categories. Are there children in all these categories who are unvaccinated?

[Response: I don’t have the answer to this handy. I know that there were a few kids in the sample that had zero vaccine receipts, but I don’t think they were in all of the categories because there were few of them. Most of the kids with 0 mercury exposure received at least some vaccines, but they were thimerosal free.]

To some extent, mercury exposure from vaccines could be used as a proxy variable for vaccine exposures. I.e. the amount of mercury would be somewhat proportional to the number of vaccines received. Are there any trends in just number of vaccines and autism? I.e. anything that would address the “too many, too soon” slogan? I do see that you discuss this somewhat on page 661

[Response: In the technical report (Volume II, Chapter 16) I show data on the the cumulative numbers of vaccines recieved as children aged. It shows that the cases and controls got the same numbers of vaccines. That chapter was not designed specifically to address your question about “too many too soon”, but it does show cases did not get more, sooner than controls.]

After Thomson(2007) came out, I recall that the CDC webpage suggested that your present study would be out in about a year. Why has this study taken so long to reach the public?

[Response: I’m not sure why the CDC web page had the overly optimistic suggestion that it would be out in about a year. To understand the timeline, I will need to explain some things about the phases of analysis, then the process of drafting the paper and getting it published. This is going to be a bit long winded, but part of it I am cutting and pasting from the technical report:

The study protocol was developed by a design group led by Abt Associates, Inc. working in close consultation with Principal Investigators from the
Centers for Disease Control and Prevention (CDC), Principal Investigators, Data Managers, and Study Managers from the each of the three HMOs, and with the study’s External Expert Consultants. Prior to recruitment and data collection, a detailed analysis plan was written for the study that specified the research questions, study design, eligibility criteria, sampling plan and target sample sizes, the form of the statistical models that would be used, the specific hypotheses to be tested, decision rules for categorizing outcome classifications, the coding of exposure variables,
the list of covariates to be used as statistical control variables, the coding of each of those variables, and decision rules for the retention or omission of each covariate in the final analysis models.

By agreement among the members of the design group, data analysis for the study was to be completed in two phases. In the first analysis phase, analysts at Abt Associates were to carry out as closely as possible the analyses specified in the plan and to do only the analyses specified in the plan. At the end of this phase, all members of the design group were invited to a meeting in Washington, DC where the first round, preliminary results were presented to the group. Prior to that meeting, the results of analyses linking exposures to outcomes had not been shared with anyone outside of Abt Associates. The second phase of analysis began with the meeting in Washington, DC. At that meeting, the design group considered the results and generated new hypotheses and questions that were to be pursued in the second phase. Over the ensuing months design team members provided written comments on the results of the preliminary analyses and made suggestions for additional analyses. The current report includes results from both phases.

The meeting in DC described in the paragraph above took place in May of 2008. We gave all of the members of the design group a couple of months to give feedback and suggestions on the analyses that they wanted in Phase II. There was a lot of back and forth there. The technical report includes results from both phases. We were well into 2009 before we (at Abt) had made it all the way through those second phase analyses. Then, drafts of the manuscript had contributions from a large number of authors (which takes a lot of time) and we sent drafts to our External Expert Consultants, made changes, replied to queries etc, then a draft had to go through CDC review which takes time, then we the publication process (getting a manuscript published in a peer-reviewed journal) takes a surprisingly long time. So, here we are in 2010.]

New thimerosal/autism paper – signal vs noise

13 Sep

The new thiomersal paper that Sully has blogged will be attacked by the antivaxxers in at least one key area. The area that will be attacked is – to those well schooled in the way good science operates – a standard way to improve the signal to noise ratio of the results. Or to put it another way, ensures ‘cleaner’ results.

From the paper:

…Children were excluded if they had the following medical conditions with known links to ASD traits: fragile X syndrome; tuberous sclerosis; Rett syndrome; congenital rubella syndrome; or Angelman syndrome…

So first of all why were children that fell within these groups excluded? As I said, the answer is to ensure better data. In order to get a cleaner signal, the more noise that can be eradicated the better.

In this instance, children who already have existing medical conditions known to be related to autism would produce noise. We already know what caused their autistic traits hence establishing a clear link to thiomersal would not be possible. In a very meaningful way, doing this does a large favour for antivax group. If these children were eradicated from the study and a clear link to thiomersal _had_ been established then denying the link would be very much more difficult.

However don’t expect the antivaxxers to see this. Or even if they _do_ see it, they will look away purposefully. They will use the fact that these children were excluded and say _”See? ‘They’ have to hide the autistic children!”_ .

When you see this tactic – and you will see it – see it for what it is. It’s simple noise generation to obscure the clear signal coming through. Thimerosal in vaccines doesn’t cause autism. And it never did.

Congenital Rubella Syndrome: a Novel Form of Mercury Poisoning?

13 Sep

I considered titling this: A peak into the upcoming book “Age of Autism?” as this seems to show us the sorts of arguments that will be made in that book.

One of the known environmental causes of autism is Congenital Rubella Syndrome, or CRS. This was discussed as part of a presentation to the IACC, What Causes Autism? The Case for an Environmental Contribution, by Dr. Philip Landrigan. (video is here, starting at about minute 79. Sorry it doesn’t embed).

In the question/answer session for that presentation on at about 114 minutes into the IACC meeting) Lyn Redwood of SafeMinds brought up a new argument–that CRS induced autism may be due to mercury. It turns out that in the 1950’s gamma globulin therapy was started as a means of preventing CRS. Gamma Globulin was injected into pregnant mothers who to prevent or reduce the rubella infections. This exposed the mother and fetus to mercury and should be considered the cause of the autism according to Ms. Redwood.

I must admit that when I heard this question I thought: “Well, here is one of the talking points we will hear from the upcoming book, ‘Age of Autism’, by Mark Blaxill and Dan Olmsted”. Their book appears to be an attempt to tie all of autism (and many other conditions) to mercury, including, I suspect now, CRS. There are other loose ends they will undoubtedly bring up and tie into the mercury hypothesis (like the existence of autistics who were born before thimerosal was invented. That will be interesting to read).

There is at least one big reason why CRS was possibly not linked to autism before Stella Chase’s work in the 1970’s. Congenital Rubella Syndrome causes major disability. Severe to profound mental retardation. There are big spikes in the California Department of Developmental Services data for severe and profound mental retardation corresponding to the CRS outbreaks of the 1960s. Why bring this up? Because for the first two decades after Kanner’s original paper, many people considered intellectual disability (mental retardation) and autism to be completely separate.

From Infantile autism reviewed: a decade of research, a review article written in 1981:

One of the chief problems has been how to handle the questions of mental retardation and organic brain disease, issues especially troublesome with regard to infantile autism. When Kanner (1943) first described the diagnostic features, he also remarked that the condition bore no resemblance to any known neurological condition and implied that autistic children had a basically normal intelligence. For over two decades afterwards, diagnosticians generally believed that the presence of mental retardation or neurologic signs ruled out the diagnosis of infantile autism in the Kannerian sense, even if the child met all behavioral criteria (Eisenberg 1966). Thus diagnosis was frequently one dimensional; a child was labeled as afflicted with either infantile autism or mental retardation, not both.

Or, to put it another way, what many people today call “Kanner’s Autism”, with intellectual disability and/or apraxia, is not what Kanner and most of the people of his time thought of as autism.

But, data, as they say, there’s a funny thing about evidence. Real data is worth more than all these blogger discussions. The paper out today from Pediatrics included immune globulins in their analysis and showed that mercury exposure prenatally and in infancy and found that these exposures did not increase the risk of autism.

Then again, the funny thing about evidence is that it is repeatable. Two previous papers showed no link between immune globulins and autism:

Maternal Rh D status, anti-D immune globulin exposure during pregnancy, and risk of autism spectrum disorders


Lack of association between Rh status, Rh immune globulin in pregnancy and autism.

So, if I am correct and “Age of Autism” the book claims immune globulins *are* a cause of autism, what can we say? We can say that the funny thing about evidence is that some people are not swayed by it. Some people will continue to push the mercury hypothesis forever.

Thimerosal in vaccines did not cause an autism epidemic

13 Sep

There have been two main theories linking vaccines to an “epidemic” of autism. Both theories have been studied. Both have been heard in the courts. Neither theory had a sound scientific basis and epidemiological data has shown that neither theories explained the increase in autism prevalence in the last 20 years.

First it was proposed that the MMR vaccine resulted in persistent measles infections that lodged in the intestines of children leading to “leaky guts” and that harmful substances were leaked into the blood, traveled to the brain and resulted in autism symptoms. This was proposed by Dr. Andrew Wakefield and has since been shown in epidemiological and other studies to be unsound. (This theory morphed for the Omnibus Autism Proceeding, the vaccine court. The argument there was that the measles virus itself traveled to the brain. Again, it is not supported by epidemiological data and is not scientifically sound).

The second theory was that mercury in vaccines from a compound called thimerosal caused autism. In that theory, it was proposed that autism symptoms were similar to mercury poisoning (autism was a “novel” form of mercury poisoning). This theory was not scientifically sound as autism symptoms are not like mercury poisoning. Previous epidemiological studies have also shown thimerosal was not behind the rising numbers of people diagnosed with autism.

In 2007 there was a study which looked at 1,000 kids aged 7-10 to see if various neurological symptoms were more prevalent in those who received higher exposures to thimerosal. Orac at Respectful Insolence blogged it and Kev posted that piece here on LeftBrainRightBrain as well. That study showed indications that in some measures children may perform more poorly with thimerosal exposure. It also showed that in some measures children may perform better with thimerosal exposure. This mixed result is (a) not very strong in either direction and (b) not very surprising when you look at a lot of different measures at the same time. Chance will result in some measures positive, some negative.

The 2007 study was published in the New England Journal of Medicine as Early Thimerosal Exposure and Neuropsychological Outcomes at 7 to 10 Years, by Thompson, et al.. (Thompson (2007))

What was missing in that report was a direct study of autism. Given the numbers of children (1,047) selected, there would only be about 10 kids with ASD expected in the group. This is too few for a strong conclusion on autism. At the time of that study it was noted that another study would follow concentrating on autism alone.

That study has just been published in the journal Pediatrics as Prenatal and Infant Exposure to Thimerosal From Vaccines and Immunoglobulins and Risk of Autism. They studied “256 children with ASD and 752 controls matched by birth year, gender, and [managed care organizations]”. I will give some details here. I expect the treatment on the Science Based Medicine and Steven Novela’s Neurologica blogs to cover the science thoroughly should you wish more detail.

Short answer: thimerosal exposure doesn’t cause an increased risk of autism. Neither thimerosal from vaccines given to the children nor thimerosal from products like Rhogam are behind the increase in autism prevalence we have seen.

It is worth noting that the authors looked at autism with and without regression.

Here is the abstract:

OBJECTIVE: Exposure to thimerosal, a mercury-containing preservative that is used in vaccines and immunoglobulin preparations, has been hypothesized to be associated with increased risk of autism spectrum disorder (ASD). This study was designed to examine relationships between prenatal and infant ethylmercury exposure from thimerosal containing vaccines and/or immunoglobulin preparations and ASD and 2 ASD subcategories: autistic disorder (AD) and ASD with regression.

METHODS: A case-control study was conducted in 3 managed care organizations (MCOs) of 256 children with ASD and 752 controls matched by birth year, gender, and MCO. ASD diagnoses were validated through standardized in-person evaluations. Exposure to thimerosal in vaccines and immunoglobulin preparations was determined from electronic immunization registries, medical charts, and parent interviews. Information on potential confounding factors was obtained from the interviews and medical charts. We used conditional logistic regression to assess associations between ASD, AD, and ASD with regression and exposure to ethylmercury during prenatal, birth-to-1 month, birthto-7-month, and birth-to-20-month periods.

RESULTS: There were no findings of increased risk for any of the 3 ASD outcomes. The adjusted odds ratios (95% confidence intervals) for ASD associated with a 2-SD increase in ethylmercury exposure were 1.12 (0.83–1.51) for prenatal exposure, 0.88 (0.62–1.26) for exposure from birth to 1 month, 0.60 (0.36–0.99) for exposure from birth to 7 months, and 0.60 (0.32– 0.97) for exposure from birth to 20 months.

CONCLUSIONS: In our study of MCO members, prenatal and early-life exposure to ethylmercury from thimerosal-containing vaccines and immunoglobulin preparations was not related to increased risk ASDs. Pediatrics 2010;126:656–664

My guess is that there will be much discussion of the methods on many websites. For now, here are the data from Table 2 and Table 3.

Table 2 (click to enlarge)

Table 3 (click to enlarge)

As with Thompson (2007) the authors will make longer reports available on their website and will allow access to the data.

This study is not the first of its kind. Here are a few of the large studies which have shown a lack of association between thimerosal exposure and autism in the past.

Thimerosal and the Occurrence of Autism: Negative Ecological Evidence From Danish Population-Based Data

Safety of Thimerosal-Containing Vaccines: A Two-Phased Study of Computerized Health Maintenance Organization Database

Thimerosal Exposure in Infants and Developmental Disorders: A Prospective Cohort Study in the United Kingdom Does Not Support a Causal Association

Autism and Thimerosal-Containing Vaccines Lack of Consistent Evidence for an Association

There are more.

One question is whether this will finally quiet those claiming an autism epidemic caused by mercury in vaccines. Unfortunately, I sincerely doubt it. This study included Sallie Bernard of SafeMinds in the acknowledgments. Ms. Bernard was also involved in the Thompson study of 2007. At that time she was listed as a “dissenting” member of the team. She submitted a letter to the NEJM discussing the reasons for her dissention, Perhaps the lack of the word “dissenting” this time is a good sign. I’ll wait and see.

The main question is how much impact this will have on the next generation of families with autistic children. I can’t but wonder that the age of the mercury hypothesis has seen its peak. Not only in research but in general acceptance.

Sharyl Attkisson blogs the Hannah Poling settlement

10 Sep

I had forgotten Sharyl Attkisson. She is a reporter for CBS news who has covered vaccines in the past, but has been silent on the issue for the past year or more.

Her recent piece shows exactly the sort of reporting that frustrated me in the past: Family to Receive $1.5M in First-Ever Vaccine-Autism Court Award

In that piece she links to her piece from 2008 on the Hannah Poling case: Vaccine Case: An Exception Or A Precedent?

Here’s a quote from that earlier piece:

While the Poling case is the first of its kind to become public, a CBS News investigation uncovered at least nine other cases as far back as 1990, where records show the court ordered the government compensated families whose children developed autism or autistic-like symptoms in children including toddlers who had been called “very smart” and “impressed” doctors with their “intelligence and curiosity” … until their vaccinations.

They were children just like Hannah Poling.

What’s still being debated is whether the Poling case is an exception … or a precedent.

So, which is it? Were there children “just like Hannah Poling” or is this the “First-Ever Vaccine-Autism Court Award”?

Actually, it is neither. This isn’t the first vaccine court award involving autism, and the other cases are not “just like Hannah Poling”.

For real information on the other nine cases, read Kathleen Seidel’s piece on Neurodiversity.com. Few, professional or amateur, can compare the the thoroughness of Kathleen Seidel. For example, one case (the first I read involving autism from the vaccine court) is Suel v. HHS. Young David Suel had tuberous sclerosis, a condition known to be associated with autism and epilepsy. Epilepsy occurs in about 60 to 90% of individuals with TS. Autism occurs in about 25-50%. David Suel’s case was declared to be a “table injury” wherein the seizures began within a set period after his DPT vaccination. What is notable about that is the table for DPT was later changed–when it was shown that DPT was not responsible for inducing seizure disorders. In other words, had David Suel been vaccinated, or just filed, after the change in the table, he likely would not have been awarded damages.

“They were children just like Hannah Poling”? Is tuberous sclerosis just like mitochondrial disease? (answer: not even close).

Shall we go on? In her recent piece, Ms. Attkisson states:

In 2002, Hannah’s parents filed an autism claim in federal vaccine court. Five years later, the government settled the case before trial and had it sealed

Not accurate. The court did not “settle” the case in 2007. They conceded the case, and they were in the process of completing the settlement when someone leaked the information to the press. The government did not “seal” the case–it is standard procedure to keep this information confidential until the settlement is completed.

But that doesn’t make a good story, does it?

Ms. Attkisson goes on:

In acknowledging Hannah’s injuries, the government said vaccines aggravated an unknown mitochondrial disorder Hannah had which didn’t “cause” her autism, but “resulted” in it. It’s unknown how many other children have similar undiagnosed mitochondrial disorder. All other autism “test cases” have been defeated at trial. Approximately 4,800 are awaiting disposition in federal vaccine court.

Mito-autism was a big thing for a while there. David Kirby took the story and ran with it–making a lot of mistakes along the way and propagating a lot of misinformation. It is unknown how many other children have similar disorders–but the researchers who studied cases like Hannah Poling have stated that cases such as hers are “rare”.

“All other autism “test cases” have been defeated at trial”.

What is conspicuous about the other “test cases” is that in none of them was it argued that the children were like Hannah Poling–i.e. the attorneys did not argue that a mechanism of autism through mitochondrial dysfunction aggravated by vaccines existed. In fact, one child named as a test case was pulled from that slot in order to argue that mitochondrial based case. The expert report filed for that child (since pulled from the Omnibus website) did not argue mitochondrial disorder or dysfunction at that time. In other words, the idea of a mitochondrial disorder being linked to autism was so alien from the cases being made by the attorneys for the families in the Omnibus that this child had to argue the case separately.

It is often pointed out that many autistics may have mitochondrial dysfunction. This is based largely on studies out of Portugal. It is left implied, and it is often believed that mitochondrial dysfunction means vaccine injury in these cases. This was the impression that David Kirby put forth and it was clearly wrong. First, mitochondrial disorders are a very broad spectrum. The type that Hannah Poling has is not the same as those detected in most autistics. Second, most reports of mitochondrial disorders and autism, including the Portugal studies, do not involve regression. Third, even amongst those children reported by the groups that identified Hannah Poling, regression was often idiopathic or followed fever clearly independent of vaccination.

I do not expect Ms. Attkisson to present the following (quality) information, so I will repeat it here:

Here are the answers to some questions posted to mitochondrial medicine experts and their answers:

When asked, to respond to the position: ‘‘I view the risk of vaccination in known metabolic disease patients to generally be outweighed by the risk of the infectious diseases being vaccinated against”

63.2% strongly agreed
31.1% agreed
0.9% disagreed
and 0.9% strongly disagreed.

Asked about the opinion that the risk of vaccination in metabolic disease was ‘‘greater than the risk of the infectious diseases being vaccinated against”

52.9% strongly disagreed
40% disagreed
3.5% agreed
and none strongly agreed

Review of the Introduction of Age of Autism – the book.

23 Aug

So begins the Olmsted/Blaxill upcoming book ‘Age of Autism’.

…instead of taking Kanner’s word for it, [we decided] to learn about these previously anonymous families ourselves. We took clues from his extensive case descriptions and started uncovering the identities of the original families. Time and again, we connected the occupations of the parents to plausible toxic exposures and especially to a new mercury compound first used in the 1930s as a disinfectant for seeds, a treatment for lumber, and a preservative in vaccines. Yes, the parents’ professions were clues— but not to their obsessions or their marriages or their parenting or their genetic oddities; instead, they pointed to a strikingly consistent pattern of familial exposures to the same toxic substance.

(emphasis authors, inserts mine)

This is the paragraph that sets the authors hypothesis out. When we look at it carefully, we can see exactly what its purpose is – its purpose is to fit a set of preconceived ideas that revolve around one central disproven hypothesis – that mercury in vaccines (thiomersal/thimerosal) causes autism.

I haven’t yet read the rest of the book but I’m pretty sure what I’m going to find. To talk about that now would just be conjecture however, so lets stick to what we have here.

According to Olmsted and Blaxill, syphilis treatment, hysteria, mental illness and a variety of modern illnesses are all caused by mercury. I’m very much looking forward to reading this section too. Olmsted & Blaxill use Pink disease (a definite form of mercury poisoning which looks nothing like autism to ‘justify’ the inclusion of these illnesses in the Introduction.

Blaxill and Omsted detail how they went on to meet “Donald T.” one of Kanner’s original cases:

By any mea sure, he has fared astonishingly well. President of his college fraternity and later the Forest Kiwanis Club, a pillar of his Presbyterian church, he had a long career at the local bank, plays a competitive game of golf, and regularly travels the world. We learned how “Donald T.” went from being the first unmistakable case of autism to the first unmistakable case of recovery.

So on one hand we have the doom and gloom of Pink disease (a foreshadow of autism according to Blaxill & Olmsted) which killed hundreds and then actual autism which doesn’t seem that bad. I’ll be very interested to see how Blaxill & Olmsted narrate Donald T.’s ‘recovery’…or could it have been that Donald T. was in fact one of the first cases of autism who also either moved ‘off the spectrum’ (as a certain percentage of autistic people do) or…y’know…he simply progressed as he got older. My guess is that Blaxill & Olmsted will reveal that Donald T. had some kind of miraculous exposure to a chelating agent or multi vitamins or some form of extreme biomed. Lets see.

The whole Introduction is about 6,000 words long. I can’t possibly attempt to review the whole thing and I won’t attempt to review the whole book either. These are the sections of the Intro that caught my eye particularly. Maybe others who have access to the Intro will tackle more. One thing you can be sure of, LBRB will be here to catch and expose the errors.

Eli Lilly halts two clinical trials of an experimental Alzheimer’s treatment

19 Aug

This has been reported in a number of places, including the New York Times in their article Lilly Stops Alzheimer’s Drug Trials.

From the NY Times:

Eli Lilly halted two late-stage clinical trials of an experimental Alzheimer’s treatment on Tuesday, representing a setback to one leading theory on treating the degenerative disease and a new blow to Lilly’s business prospects.

One defining feature of Alzheimers disease is the presence of amyloid plaque in the brain. The now-halted clinical trial was for a drug which reduces this plaque.

The basic idea is fairly straightforward: if plaque is present in the brains of those with Alzheimer’s, removing the plaque may help reduce or reverse the symptoms. Instead, researchers were finding that the drug was making symptoms worse. Again from the times:

The company said patients who had taken the drug, intended to reduce plaque in the brain, actually showed worse cognitive functioning and less ability to perform daily living tasks than patients who had taken a placebo.

Why bring this up on an autism blog? Because this trial gives a good example of why I am very concerned about the use of untested therapies on autistics. It isn’t because of some objection to a “cure”. There is no existing autism cure. There is no autism cure proposed or in any stage of a clinical trial. While there is some very good and important discussions about any potential cure, it is for the present a hypothetical discussion. No, it isn’t the cure debate which drives me. It is safety. Plain and simple.

Consider autism therapies (both alternative and off-label) from a viewpoint of safety for the moment with the lessons learned from the Alzheimer’s trial.

Clinical trials are all about safety and efficacy. Is the therapy (drug) safe? Does it work? Before a clinical trial is even started, there has to be some reason to believe that the therapy would be safe and effective. Researchers have to ask the question, “what will this do?” In the Eli Lilly Alzheimer’s trial, they had reason to believe that the drug would reduce amyloid plaque. They had (I assume) some earlier trials to prove the drug reached some level of safety. With that in hand, Eli Lilly went forward to large-scale testing with people and they found that, at least for their test group (people with somewhat advanced Alzheimer’s disease), the drug was harmful.

From the NY Times story:

Lilly’s drug was intended to reduce production of so-called amyloid beta plaques in the brain by inhibiting the activity of an enzyme called gamma secretase.

Dr. Siemers of Lilly said the failed trials might indicate that too much reduction in amyloid beta unexpectedly harms cognitive functions, or it may be that the problems arose from the drug’s effect on some 20 other proteins.

Unintended and unforeseen consequences.

Consider alternative therapies being applied to autistics. For example, consider anti-inflammatory drugs. These are existing drugs used off-label, so some safety data are available. There is evidence of inflammation in the brains for some autistics, so why not treat it?

Because we don’t understand why there is inflammation in the brains of autistics. Because of that, we don’t know if there are any unintended consequences of anti-inflammatory therapies. From a story last year in the Chicago Tribune, this section discussing the team from Johns Hopkins/Kennedy Krieger which first published on neuroinflammation in autistics:

“THERE IS NO indication for using anti-inflammatory medications in patients with autism,” the [Johns Hopkins] team wrote.

Meddling with neuroinflammation could actually be a terrible mistake, said co-author Dr. Andrew Zimmerman, director of medical research at the Center for Autism and Related Disorders at the Kennedy Krieger Institute in Baltimore.

“It may actually be an attempt of the brain to repair itself,” said Zimmerman, a pediatric neurologist. Suppressing the immune response “could be doing harm.”

There are other classes of alternative therapies used in autism. Therapies which most likely are doing nothing beyond the placebo effect are in one class. For example, homeopathy. I don’t spend a lot of time writing about homeopathy. In fact, I don’t know if I have blogged about it at all. Even though it is bad science, it isn’t really dangerous. Another class of alternative therapies are those based in really bad science and which carry the potential of harm. Lupron comes readily to mind. Lupron therapy is based on two levels of very bad science. First, that autism is caused by mercury poisoning. Second, that reducing testosterone in the body will aid it in eliminating mercury. Lupron has been through clinical trials (not for autism) demostrating some level of safety, there are serious known side effects. Worse, the manner in which it is used in autistic children is very problematic–delaying puberty.

Back to the Alzheimer’s trial–I actually welcome the trial itself. I consider those who undertake clinical trials to be very brave individuals. I for one hope there are effective therapies for Alzheimer’s and other forms of dementia soon. It is a great fear for most, if not all, of us that we spend the last years of our lives with dementia. For the parent of a disabled child, this fear is only compounded. The thought of spending my last years draining resources I would rather leave to my child is one of the worst futures I can imagine.

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