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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.

Autism researchers want your input: Autism Life Histories at Columbia

17 Sep

Prof. Peter Bearman’s group at Columbia has done and is still doing much in the way of autism epidemiology research. We have discussed many of his group’s papers here on LeftBrainRightBrain. Prof. Bearman’s group now has a website up, Understanding Autism.

As a part of their continuing research into autism, the Bearman team has launched a new project, AutismLifeHistories.org. This is essentially a survey to collect information from parents about their child’s

edit to add–here is how I intended that sentence to read
This is essentially a survey to collect information from parents about their child’s history, but nothing prevents a self-advocate from submitting information on him/her self.

The full description is below, but here is a shorter version from page 1 of the survey:

The purpose of this online survey is to learn about how you recognized your child’s autism, sought professional help and navigated the system of services. We hope that these stories help us arrive at a better understanding of the difficulties of the road to diagnosis and service provision.

While we do not believe that the content and the nature of the questions presented in this survey will cause you any discomfort, your participation is absolutely voluntary throughout the survey. This means that you are free to leave this survey at any time you wish. We will only read your responses if you complete and submit your responses.

It took me about 10 minutes. One could easily spend less.

Here is the longer description of the project:

Autism Life Histories
Dear Parent,

We are researchers at Columbia University’s Institute for Social and Economic Research and Policy studying autism. We are currently collecting life stories from parents about their experiences in recognizing their child’s autism, seeking professional help and navigating the system of services.

The goal of this project is to gain a better understanding of the road to diagnosis. Parents have different experiences and observations of their child’s development and they have different personal resources with which they access care and services. Parents also differ in the type and extent of their support networks and social relations. And finally parents make different decisions in their quest for obtaining the right diagnosis and care for their child. We are eager to hear about how these factors affected your experience and your child’s experience with autism.

We invite you to tell your story by completing a semi-structured survey in which your identity will remain confidential. In fact, this task is less of a survey and more of a conversation between you and us. There are three main sections to this conversation. The first section is set up to learn about you; we ask you a series of short questions. The second section is designed to learn about your child; we ask a series of short questions about his/her age, birth year and place and interaction with other children. The third section provides you with unlimited space to write about your story in recognizing your child’s autism. We hope you will decide to talk with us.

We thank you in advance for taking the time to read through this invitation and look forward to getting to know you. Please feel free to contact us via e-mail at understandingautism@columbia.edu with any questions that you may have. Please be assured that we will not share your story with anyone other than authorized members of our research team. No one else will have access to it.

To share your story, please click on the following link talk-to-us to the online survey.

Sincerely,

Peter Bearman, Principal Investigator
Cole Professor of the Social Sciences

Autism causation and the Hepatitis B vaccine: no link

16 Sep

One of the primary subjects for those promoting vaccines as a primary cause of autism is the Hepatitis B vaccine. This vaccine is given at birth and represents a child’s first exposure outside the womb to a vaccine and, in the old days, to thimerosal. David Kirby attempted to link the rise in autism prevalence to the introduction of the HepB vaccine. Others have claimed that the rates of special education placements are 9 times higher amongst children given the HepB vaccine at birth. Here is the abstract for (Hepatitis B triple series vaccine and developmental disability in US children aged 1–9 years rel=”nofollow”)

This study investigated the association between vaccination with the Hepatitis B triple series vaccine prior to 2000 and developmental disability in children aged 1– 9 years (n¼1824), proxied by parental report that their child receives early intervention or special education services (EIS). National Health and Nutrition Examination Survey 1999–2000 data were analyzed and adjusted for survey design by Taylor Linearization using SAS version 9.1 software, with SAS callable SUDAAN version 9.0.1. The odds of receiving EIS were approximately nine times as great for vaccinated boys (n¼46) as for unvaccinated boys (n¼7), after adjustment for confounders. This study found statistically significant evidence to suggest that boys in United States who were vaccinated with the triple series Hepatitis B vaccine, during the time period in which vaccines were manufactured with thimerosal, were more susceptible to developmental disability than were unvaccinated boys.

The recent study on thimerosal and autism gives us a look at how the Hepatitis B vaccine might (or might not) be linked to autism. Exhibit 16.1 on page 82 of volume 2 of the technical report is a graph of HepB vaccine uptake among autistic children (AD) and non-autistic children (controls)

Here is that exhibit, showing the total number of vaccines (count) and amount of thimerosal (amt) for all vaccines and for HepB alone:

Price-HepBGraphs1-copy[1]

The top right graph shows the number of HepB vaccines for autistic kids (solid line) and non-autistic kids (dotted line). They are, to all intents and purposes, the same.

Take a look at the birth dose. Not every kid got it. Maybe about 1/2 got the birth dose at birth, and about 2/3 got it within the first few days.

If the birth dose of HepB caused autism to any significant degree, I would expect to see a higher percentage of autistic kids than non-autistic kids getting that shot. It just didn’t happen. Take a closer look at that graph:

Price-HepBGraphs2[1]

The same percentage of got the HepB shots–all 3 of them– as non-autistic kids.

Still wondering about that birth dose? Let’s zoom in on the graph:

Price-HepBGraphs3[1]

Those lines are right on top of each other.

The HepB hypothesis won’t go away. Just like the thimerosal hypothesis or the MMR hypothesis. Just today, Mark Blaxill and Dan Olmsted put out a very long post at the Age of Autism blog pushing the idea. They use the bad and worse studies from Thoughtful House on infant macaques to bolster their arguments.

The funny thing about evidence is, some people never accept it.

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.]

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.

MMR vaccine damaged man

30 Aug

Jackie Fletcher is well known to many – she routinely insists the MMR jab is dangerous despite reams of evidence to the contrary. However, a panel in the UK has found that her son, Robert, was damaged by the MMR vaccine he was administered.

I nearly didn’t blog about this. Why? Well, this blogs predominant focus is autism and Robert did not and does not have autism. The panel in this case found that the MMR caused seizures and mental retardation. Its difficult therefore to get a ‘hook’ into this story. As Mike Fitzpatrick is quoted as saying in the Daily Mail:

It is a very important principle that parents should be compensated in cases of this kind…

and he’s absolutely right. Thats why the Vaccine Damage Payment Unit exists in the UK.

Like any other form of medical procedure, vaccines are not 100% safe. I can’t recall anyone anywhere ever making that claim. What they _are_ however, is very safe indeed. Robert Fletcher was injured and has been compensated. I might even agree with his mum that the amount is ‘derisory’. Robert will need full time care all of his life and £90,000 ($140,000) is nowhere near enough. However, campaigners uninterested in Robert’s day to day needs say that:

Campaigner Polly Tommey, who edits the magazine The Autism File and believes her son Billy is autistic because of MMR, says: ‘This is fantastic news. Now doctors can’t tell me that the MMR is safe.

‘This payout is evidence that it is not safe. It’s interesting that they will look at epilepsy and not autism, and you have to ask why.

‘Is it because the compensation would be billions?’

I very much doubt that any doctor, anywhere has ever told any recipient anywhere that any vaccine is 100% safe. If they did, they were liars.

However, this payment, far from being ‘evidence that it is not safe’ (a bizarre claim) is more like a recognition that the Vaccine Damage Payment system is working as it should. A man was vaccine damaged and was compensated as a result.

As for the claim that ‘they’ will not look at autism, this is simply incorrect. Robert, does not have autism and therefore it would be impossible in this case to look at autism. I would imagine if someone with autism was adjudged to be damaged by their MMR vaccine, Ms Tommey might have a point. As that has not happened, she does not. This kind of fear-mongering by the likes of Tommey is no doubt why the panel made the clear point:

We would stress that this decision is fact-specific and it should not be seen as a precedent for any other case.

In particular, it has no relevance to the issue… as to whether there is a link between the MMR vaccine and autism.

And Fletcher goes on to claim:

Claims for autism are not considered. There are 120 MMR cases waiting to be heard, but none is for autism…

So why should that be? Why is autism apparently ‘excluded’?

Its because the science – both epidemiological and clinical clearly shows that MMR does not cause autism. And that is not the odd paper here and there. We are talking about overwhelming science that shows that the whole autism/MMR connection is simply false and was built up by one man too stupid to admit his clear errors and a mass media keen to build sensation out of this same man’s ego.

Tommey, Fletcher and all others who believe that there’s some kind of conspiracy afoot to block autism from MMR causation cases need to understand the science involved and that unless some new science is forthcoming that establishes MMR as a causative agent in regards to autism then the simple fact of applying for compensation listing the MMR as a cause of their child’s autism is _always_ going to be an immediate strikeout.

Campaigners need to start seeing this event for what it _really_ is – compensation for a vaccine damaged man – and not as what it isn’t – evidence that MMR is inherently unsafe or that theres some mysterious conspiracy to prevent autism from being linked to MMR.

The autism ‘epidemic’ no more

17 Aug

OK, so its well known to LBRB readers that I don’t think its ever been scientifically established that there has been such a thing as an autism epidemic but even so, looking at why autism numbers have changed over a certain period of time – the period of time people believe is part of the ‘epidemic’ – should be a good way to determine what contributed to that time periods rise in autism.

So thats what Peter Bearman did. Summed up well in this weeks New Scientist, Bearman’s study offers the first look at what actually did cause the ‘epidemic’.

Better diagnosis
Diagnostic changes are the most important influence. After 1987, the definition of autism used in California was broadened several times. Bearman and his colleague Marissa King examined the medical records of around 7000 Californian children with autism and found that one in ten had initially been diagnosed with mental retardation. Extrapolated to the state as a whole, they estimate that this change in diagnosis created almost 5000 extra cases of autism between 1993 and 2005, or 26 per cent of the increase of recorded over that period.

Greater awareness
Social influence accounts for another big chunk of the overall increase. Parents are more aware of the disorder than they used to be, and so those whose children who have mild forms of autism have become more likely to seek out diagnosis.

Bearman and his colleague Ka-Yuet Liu quantified this effect. They first estimated how the chances of a child being diagnosed with autism increase if he or she lives close to a child that has already been diagnosed. They then plotted the addresses of children with and without autism in California to calculate the number of children who had grown up close to a child diagnosed with the condition. They were then able to calculate the fraction of extra cases that would have been diagnosed as a result of social interactions. They put this figure at 16 per cent.

Older parents
The final contribution to the rise in diagnoses comes from demographics. Couples in California are having children later in life, as they are in much of the rest of North America and Europe. That is pushing up autism rates, because autism is triggered by genetic mutations that older parents are more likely to pass on to their children.

Bearman and King calculated that these older parents are responsible for 11 per cent of the extra autism cases.

So these total 53% of the so-called ‘epidemic’. What about the missing 47%? Well, Professor Roy Grinker says:

Autism used to be highly stigmatised, in part because it was thought to be due to poor parenting. The removal of that stigma has made doctors and parents more willing to recognise the disease, which will have contributed to [some of] the extra cases…This and other social causes, together with uncertainty in the number of cases that can be attributed to the factors already studied by Bearman, could account for much or all of the unexplained half

But note Grinker doesn’t say it definitely does. This is because he knows as a careful scientist it hasn’t been looked at.

So what can we take from Bearman’s work? In my opinion we can take the fact that as soon as the questions regarding non-environmental causes were actually looked at and studied, there were numerical values that could be applied to their contribution. There are other non-environmental causes which Bearman didn’t look at which would probably be found to contribute to the other half.

What about the alleged environmental causes? It would not surprise me in the least if it were found that there were some. But as to what they are, the environmental lobby are still so hung up on vaccines they don’t seem to want to look at other possible environmental issues. Maybe its time they dropped the vaccine nonsense and got involved in some decent research. Just a thought.

Diagnosis of autism occurs much later than it should among Medicaid-enrolled children

4 Aug

This from a recent study by Prof. David Mandell’s group. The abstract is below:

Psychiatr Serv. 2010 Aug;61(8):822-9.
Age of diagnosis among medicaid-enrolled children with autism, 2001-2004.

Mandell DS, Morales KH, Xie M, Lawer LJ, Stahmer AC, Marcus SC.
Abstract

OBJECTIVE: This study examined child- and county-level factors associated with age of diagnosis of autism among Medicaid-enrolled children and the change in age of diagnosis over time. METHODS: National Medicaid claims from 2002 to 2004 were used to identify age of diagnosis and characteristics of children younger than ten years old with a diagnosis of autism (ICD-9 codes 299, 299.0x, or 299.8x). These data were linked to county-level education and health care variables. Linear regression with random effects for state and county was used to examine associations between these variables and age of diagnosis. RESULTS: A total of 28,722 Medicaid-enrolled children newly diagnosed with an autism spectrum disorder were identified. Their average age of diagnosis was 64.9 months. Adjusted average age of diagnosis dropped 5.0 months for autistic disorder and 1.8 months for other spectrum disorders during the study period. Asian children were diagnosed earlier than children in other racial or ethnic groups, although these differences were much more pronounced for other spectrum disorders than for autistic disorder. Children eligible for Medicaid through the poverty category were diagnosed earlier, on average, than children who were eligible through disability, foster care, or other reasons, although this difference decreased over time. Children in large urban or rural counties were diagnosed later than children in small urban or suburban counties. CONCLUSIONS: Findings showed that diagnosis of autism occurs much later than it should among Medicaid-enrolled children, although timeliness is improving over time. Analyses suggest that most of the observed variation is accounted for by child-level variables, rather than county-level resources or state policies.

PMID: 20675842 [PubMed – in process]

The age of diagnosis in California for the general population was 3 years by 2000 (falling from 6 in 1992) according to a recent paper by Bearman’s group at Columbia. Why are medicaid children diagnosed later?

I find it odd that children on medicaid due to poverty are diagnosed earlier than children “eligible through disability, foster care, or other reasons”. Naively, I would expect the opposite: that children already identified with a disability would be under greater scrutiny and more likely to receive evaluations to determine an ASD diagnosis.

Much more can be said about this, but I will stop with “Diagnosis of autism occurs much later than it should among Medicaid-enrolled children”. This is just wrong. We as a society should take better care of our most vulnerable.

More unidentified autistic adults found

17 Jul

One of the recurring themes heard in online discussions of autism is “where are the autistic adults?” The low number of identified adults is used as evidence of an epidemic and used to promote the vaccine-causation hypothesis.

A number of studies have started looking at adult populations and they always find a greater number of autistic adults than previously identified. Probably the largest study and the most discussed is one performed by the NHS in the UK which found a prevalence of about 1% in adults.

The NHS study looked at adults in the general population, outside of any institutional type setting.

One complaint that is often raised is where are the more severely challenged adults? The “obvious” autistics? How could they have been missed. Studies by Prof. Peter Bearman at Columbia and Prof. David Mandell have shown that, yes, we have miss counted autism in more challenged groups in the past.

Now a recent study from Iceland looks at autism in adults in Reykjavik with intellectual disabilities. They found that there were twice as many autistic adults than previously thought.

Prevalence of autism in an urban population of adults with severe intellectual disabilities – a preliminary study.

Saemundsen E, Juliusson H, Hjaltested S, Gunnarsdottir T, Halldorsdottir T, Hreidarsson S, Magnusson P.

State Diagnostic and Counselling Centre, Division of Autism, Kopavogur, Iceland.
Abstract

Background Research on the prevalence of autism in Iceland has indicated that one possible explanation of fewer autism cases in older age groups was due to an underestimation of autism in individuals with intellectual disabilities (IDs). The present study systematically searched for autism cases in the adult population of individuals with severe ID living in the city of Reykjavik, Iceland. Methods Potential participants (n = 256) were recruited through the Regional Office for the Affairs of the Handicapped in Reykjavik. First, a screening tool for autism was applied, followed by the Childhood Autism Rating Scale and finally the Autism Diagnostic Interview-Revised (ADI-R). Results The point prevalence of severe ID was 3.7/1000 (95% CI 3.2-4.1) with a male-female ratio of 1.2:1. Participation rate in the study was 46.5%. Participants were younger than non-participants and more often residents of group homes. The prevalence of autism was 21% (25/119) (95% CI 14.7-29.2) with a male-female ratio of 1.8:1. Of the individuals with autism, 10/25 (40%) were verbal according to the ADI-R definition, and 18/25 (72%) had active epilepsy and/or other neurological conditions and handicaps. Conclusion The study identified twice the number of autism cases than those previously recognised within the service system. Autism is a prevalent additional handicap in individuals with severe ID, which should always be considered in this population. There are indications that the estimated prevalence of autism found should be considered minimal.

Does this show that there has been no “epidemic”? No. But it does show (again) that the idea that autistics are so obvious that they couldn’t be missed is, well, a myth.

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