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New study on inflammatory bowel disease and autism: Prevalence of Inflammatory Bowel Disease Among Patients with Autism Spectrum Disorders.

12 Aug

People with developmental disabilities often have additional medical issues at rates higher than the general population. For example, heart problems are more common in the Down Syndrome population and Timothy Syndrome. Hip dislocation is common among those in the Fragile X community. Mental health conditions and neurological disorders are very common in autistics (but somehow those are rarely mentioned in discussions of autism and comorbidities).

When it comes to autism parents online, perhaps the most talked about autism comorbidity is gastrointestinal disease. And, in specific, inflammatory bowel disease. This is a lasting legacy of Andrew Wakefield’s attempt to link the MMR vaccine and autism (an effort which set back work on autism and GI disease by a decade or more–see Blame Wakefield For Missed Autism-Gut Connection).

Mr. Wakefield’s assertion was that the MMR vaccine leads to a unique form of IBD (he dubbed it autistic enterocolitis, a condition which doesn’t appear to exist) and this somehow leads to autism. The model also asserts that autism rates have climbed with the introduction of the MMR in the UK (an argument that fails when when considers when the MMR was introduced in the U.S., but I digress). Given the Wakefield model, including the claim that the MMR has played a major role in the “autism epidemic”, we would expect a large fraction of autistics should have IBD.

With apologies to autistics with IBD for taking so long on this introduction–this all begs the question of what is the prevalence of IBD in the autistic population? Well, a recent study discusses this:

Prevalence of Inflammatory Bowel Disease Among Patients with Autism Spectrum Disorders.

Before we get to the prevalence let’s consider the important points. First–IBD does exist in autistics. Given communication issues and sensory issues, any medical condition is serious in the autistic population. Second–IBD is more prevalent in the autistic population. What this may say about the biology of autistics and the developmental trajectory is not discussed in the abstract of this study.

Finally let’s ask how big is the prevalence of IBD in the autistic population? The study looked at two sample populations. In one population 7 out of 2728 (0.26%) autistics had IBD. For another, 16 of 7201 (0.22%). Just because the prevalence is small doesn’t mean this isn’t an important issue for the autism communities. But, let’s face it, the claims of high and rising IBD prevalence in the autism community–the claims by Mr. Wakefield to support his attack on the MMR vaccine–are just not true. And, yes, this also means that people who think that all or most autistic kids should be treated for IBD are also not doing a service. Yes, treat people with IBD. But no, don’t assume autism = person with IBD.

The fact that IBD is not that common in autistics is not really that new. I recall the press conference for the MMR/autism study by Hornig et al.. One thing that slowed the study was the fact that there weren’t that many autistic kids whose symptoms really indicated the need for a colonoscopy. Contrary to some practitioners who seem to believe that all autistics should be ‘scoped.

Here’s the abstract from the study:

The objective of this study was to measure the prevalence of inflammatory bowel disease (IBD) among patients with autism spectrum disorders (ASD), which has not been well described previously.

The rates of IBD among patients with and without ASD were measured in 4 study populations with distinct modes of ascertainment: a health care benefits company, 2 pediatric tertiary care centers, and a national ASD repository. The rates of IBD (established through International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes) were compared with respective controls and combined using a Stouffer meta-analysis. Clinical charts were also reviewed for IBD among patients with ICD-9-CM codes for both IBD and ASD at one of the pediatric tertiary care centers. This expert-verified rate was compared with the rate in the repository study population (where IBD diagnoses were established by expert review) and in nationally reported rates for pediatric IBD.

In all of case-control study populations, the rates of IBD-related ICD-9-CM codes for patients with ASD were significantly higher than that of their respective controls (Stouffer meta-analysis, P < 0.001). Expert-verified rates of IBD among patients with ASD were 7 of 2728 patients in one study population and 16 of 7201 in a second study population. The age-adjusted prevalence of IBD among patients with ASD was higher than their respective controls and nationally reported rates of pediatric IBD.

Across each population with different kinds of ascertainment, there was a consistent and statistically significant increased prevalance of IBD in patients with ASD than their respective controls and nationally reported rates for pediatric IBD.

By Matt Carey


Kaiser Permanente starts the Autism Family Biobank Study

10 Aug

Kaiser Permanente has a long history of autism research. They’ve performed a number of epidemiology studies, including many on environmental risk factors and also the recent study on The health status of adults on the autism spectrum. They have recently embarked on a large study, the Kaiser Permanente Autism Family Biobank Study.

Sign up online
Study Flyer

You can also find picture books (social stories) for the sample donation process on the Autism Family Biobank website.

From the FAQ for the study, What is the KP Autism Family Biobank?

The KP Autism Family Biobank is a study of Kaiser Permanente Northern California children and young adults with Autism Spectrum Disorder (ASD) and their biological parents. The
study seeks to enroll 5,000 affected children plus their parents (for a total of 15,000 participants) to create a collection of genetic material and information for future research. Dr. Lisa Croen is the principal investigator of the study.

Autism genetics has turned out to be a very complex question. There’s no single “autism gene” but autism clearly has a large genetic component.

What does that mean in practical terms? We need a lot of data to understand the question of autism genetics. And that’s a big piece of what this study will do: bring a lot of data to bear. And not just genetic data. This is a key part of this study and can’t be stressed enough. Kaiser provides healthcare. They have electronic records on their patients. And these patients are the pool from which they will draw their study subjects.

Or to put it simply–they will be able to not only say, “these genes are associated with autism” but “these genes are associated with autism and low verbal skills, while these other genes are associated with autism and regression.” (to give a hypothetical example).

To do this they need a lot of people to participate. They are going to get 5000 autistic kids involved. And they won’t stop there: they will also include parents. That makes 15,000 participants. Not all genes are inherited. With the parents involved, Kaiser can can see if genes associated with autism are inherited or not.

Now many parents will ask (and it’s a valid question), “OK, what will this do for my kid?” It takes time (not a lot, but some) to participate and lots of kids don’t like doctor visits. But consider this: genetics helps people understand biology. With a better understanding of biology, one can make progress towards treatments. There’s a reason why some of the treatments proposed for autism came from research in Fragile-X. People have spent a lot of time studying this genetic condition and that focus has led to proposed treatments.

Or to put the short version of the message out–this isn’t just another genetics study. It’s bigger (15,000 people!) and brings a lot of value with the clinical data that Kaiser has. There’s a chance to have a big impact to better the lives of autistics. If you are a Kaiser member in the study area, please consider participating.

Links and recent news:

Sign up online
First KP Members Join Autism Family Biobank
Kaiser to look for autism’s causes in large-scale study
Study Flyer

By Matt Carey

Disclosure: I serve on a community advisory board for Kaiser. It is a volunteer position (I.e. I get no pay) and will not benefit from this study any more than anyone else in the autism community. And the decision to conduct this study was made before I became involved with Kaiser.

IACC Presentation by Lisa Croen: Psychiatric and Medical Conditions Among Adults with ASD

20 Nov

The last meeting of the previous Interagency Autism Coordinating Committee (IACC) was a workshop on under recognized co-occurring conditions in ASD. One of the speakers was Lisa Croen of Kaiser Permanente. She spoke about psychiatric and medical conditions among adults with ASD. Much of this work (and more) was presented as a webinar at SFARI. This work was also presented at IMFAR.

If you can find the time to watch the video (it’s 17 minutes long), it’s well worth it. This is the sort of work we just haven’t seen before now–a look at medical needs of autistic adults. If you don’t have that time, here are a few highlights.

First consider the sort of medical conditions that get a lot of attention in the pediatric population: Sleep, GI and immune. For the pediatric population, one can watch the presentation by the Lewin group that was also given at the IACC workshop: IACC Co-occurring conditions workshop: Lewin Group presentation on co-occurring conditions in autistic children in the U.S..

In adults, GI, sleep and immune conditions are found more often in the autistic population than in the general population. Moderately more often. Interestingly, thyroid conditions are 2.5 times more common (compare this to GI disorders, which are 1.3 times more common).

croen 3

By contrast, psychiatric conditions like anxiety, depression and suicide attempts are even more common in the autistic population. Schizophrenia is 22 times more common.

croen 1

Neurologic conditions are also more common in the autistic population. Parkinson’s is 32 times more common in autistics. Dementia is 4.4 times more common.

croen 2

This is the sort of work I’ve been calling for since even before I was appointed to the IACC. The autism parent community and the research community spends a lot of time talking about learning about kids and getting tools into the hands of pediatricians. But what about adults? We know that epilepsy often has an onset about puberty for autistic kids. We know that for another developmental disability, Down Syndrome, early onset dementia is relatively common. But what is going on right now with adults? What is do we, parents and autistics, have to plan around for the future?

If I recall correctly, the last comment I made as a member of the IACC had to do with this study.

Those are exactly the kind of things that frankly scare the heck out of me and I would like to know more about. And know there’s something on the horizon I need to know about and if there is a way to intervene with adults.

By Matt Carey

IACC Co-occurring conditions workshop: Lewin Group presentation on co-occurring conditions in autistic children in the U.S.

4 Nov

Anjali Jain of the Lewin group presented on data they have collected from medical records about the prevalence of co-occurring conditions found in autistic children in the U.S.. This presentation was made to the Interagency Autism Coordinating Committee in Sept. 2014. (the original video is here, and the Lewin Group talk started at about timestamp 17:50.  The original has closed captioning).

Some of the most common co-occurring conditions are anxiety and depression. In fact, mental health conditions are found in about 70% of autistics. Similarly, neurological conditions and neurodevelopmental disorders are found in about 70% of autistics. By comparison, GI+nutritional disorders (which include areas like allergies), which get a great deal of attention, are found in about 20% of the autistic population. While large, this is much less common than the 70% rates found for mental health and neurodevelopmental disorders.

Another interesting finding was that autistic children are seen more often for treatment of infectious diseases. If the risk for serious problems from infectious diseases is higher in autistic children, this makes the decision of many autism parents to stop vaccinating their children even more problematic.

The full video (with closed captioning) can be found here:

By Matt Carey

Recent Autism Gastrointestinal research funded by NIH

24 Jul

There are many parent advocates asking for research into gastrointestinal disorders and autism. My own anecdotal observations have been that these same parent advocates are of the belief that no work is ongoing. There are a number of projects ongoing and I’ve tried in the past to make that point (What projects are being funded in autism research? Part 1: vaccines and GI issues). I found 14 projects, nearly $3M in 2010. I found 11 projects for $1.7M in 2009.

I thought it time to revisit this question. I’m using a different data source–the NIH RePORTER database. Because of that these projects are those funded by NIH. Other Federal groups can and do fund autism research. Also private organizations like Autism Speaks

Below are the projects I found for the past few years. There are projects on epidemiology, treatment and biology.

While I think that the funding agencies could do a better job informing the communities about these projects, I sincerely wish that the parent advocacy groups calling for this research would inform their members that it is going on. I am actually very curious as to why they have not done that.


Brainstem and autonomic circuitry, though understudied in neurodevelopmental disorders, are implicated in pathophysiology and co-occurring medical conditions, such as gastrointestinal disturbances (GID). The goal of this R21 project is to fill this knowledge gap, based on significant preliminary data.


The overall goal of our program is to (1) identify CK1 [Casein Kinase 1] inhibitors suitable for development as therapeutic agents and (2) to use these agents to investigate the suitability of CK1 inhibitors for addressing specific behavioral features of the complex, multi-symptom disorder known as autism.

The CADDRE SEED studies are multiyear but I haven’t listed all the grants. So the amount is much higher than even the substantial sums noted below.







SEED will address hypotheses including: ASD phenotypic variation, including the pattern of clustering of core symptoms, timing of onset, cognitive status, and presence of medical and psychiatric co-morbidities; gastrointestinal features; genetic variation and interaction with environmental risk factors (GxE); infection, immune function, and autoimmunity factors; hormonal factors and maternal reproductive characteristics; and sociodemographic and lifestyle factors.


Based on compelling preliminary evidence, this project aims to explore the potential connection between GI barrier defects and altered behavior in preclinical models of autism. Our long-term goal is to explore possible serum biomarkers for ASD diagnosis, and potentially develop a novel probiotic therapy for at least a subset of children with ASD with GI issues.

2013 projects

TREATMENT OF MEDICAL CONDITIONS AMONG INDIVIDUALS WITH AUTISM SPECTRUM DISORDERS $488,568 (also, $339,591 in 2012, $264,726 in 2011, $578,006 in 2010, $535,209 in 2009, and $465,840 in 2008)

The life-long impairments in communication and social function are often complicated by the presence of medical comorbidities, including epilepsy, (and epileptiform discharges), gastrointestinal disturbances and sleep disorders.


The proposed research is relevant to public health because the discovery of a novel function of NIBP/NFkB signaling in enteric neurons and glial cells is ultimately expected to increase the understanding of the pathogenesis of gastrointestinal diseases. It also shed light on the therapeutics for gastrointestinal inflammation and functional disorders.


This project seeks to answer fundamental questions about the connection between early development of gastrointestinal (GI) problems (constipation, diarrhea, vomiting, etc.) and autism spectrum disorders (ASD)

From 2011


A number of anecdotal reports have linked autism with gastrointestinal (GI) dysfunction; most notable among these are reports that autism is associated with “leaky gut” syndrome. Microbial translocation (MT) is the process by which bacteria or microbial byproducts permeate through the wall of the GI Tract (or other abnormally porous mucosal barriers) into the bloodstream. The microbial byproducts would then stimulate the immune system, which could have secondary effects on CNS functioning, or the byproducts could have a direct neurotoxic effect. We conducted assays of MT products in children with autism (from blood and CSF), as well as typically developing children (blood samples only).


Our ongoing phenotyping studies will be used to identify a cohort of children with autism who also have significant gastrointestinal symptoms in order to address this potentially important subgroup of patients.


By Matt Carey

No, the autism prevalence in Denmark did not go down with the removal of thimerosal (again!)

17 Jul

There’s a story that goes around the vaccine/autism groups that, contrary to published reports, the autism rate in Denmark went down after thimerosal was removed from their vaccines. Of course, this is all part of a cover-up. I discussed this previously in No, the autism prevalence in Denmark did not go down with the removal of thimerosal. In that piece, I looked at a number of published studies and found that the autism rate in Denmark has continued to climb post thimerosal. Later, a study came out which in one place listed autism prevalence vs year for Denmark, and I discussed that as Autism, Denmark and again no link with vaccines.

Denmark removed thimerosal from pediatric vaccines in 1992. One of the graphs I created from the published data is here:

See how the prevalence of childhood autism (autistic disorder, dark purple bars) is higher for all birth years post 1992? ASD prevalence (lighter bars) is more complex–it peaks. ASD prevalence is higher for most years after 1992, but there is that peak. At the time I speculated that someone would rework these data and claim “see! there was a drop! Vaccines cause autism!”. It would be very dishonest and misleading, so I’m not surprised to see that the Age of Autism blog did exactly that.. Let me take a second to discuss how this is dishonest. First, the prevalence of childhood autism is always higher post 1992. This is what the Age of Autism and similar sites consider “real autism”, but they just ignore that. Even one of their own commenters asked about this and was ignored. Next, even with the apparent peak in ASD prevalence, the prevalence is higher for kids borh after 1992. If thimerosal was the primary cause of autism (or even a large cause), the prevalence should have dropped immediately after 1992 in both the childhood autism and ASD groups. It didn’t.

Why is there a peak in the ASD prevalence? Most likely years of follow up. Kids with, say, Asperger syndrome are diagnosed later. The data in the graph above were for kids diagnosed by 2010. So the kids in birth year 2004 were only 6 when the study was performed and fewer of them were diagnosed by the time the study was performed.

At age 6, many autistics remain undiagnosed. If you are skeptical that kids are diagnosed late, read on.

Another study has been recently published on autism prevalence in Denmark, The increasing prevalence of reported diagnoses of childhood psychiatric disorders: a descriptive multinational comparison. In this study they compared autism prevalence as well as ADD, Tourette syndrome and OCD in 3 different countries and noted that the trends were similar. The Simons Foundation SFARI blog has covered this in Autism not the only neurodevelopmental disorder on the rise.

Thimerosal was removed in Denmark in 1992. The autism prevalence increased after that. Same for Sweden. I’m not sure when Finland phased out thimerosal, but I suspect it’s about the same time. In which case, again, the rise in prevalence following the removal works against the thimerosal hypothesis.

This all said, what caught my eye was the supplemental material available with the paper. They show autism prevalence for various birth cohorts by age. For example, for kids born in 1990-1992, the authors give the autism prevalence at age 5, 8, 10, 15 and 20.

But, you say, it’s autism prevalence, how can it change with age? Autism is obvious and once the DSM IV was published, everyone has the exact same idea of who is autistic, right? Let’s use these data to see. Autism prevalence is almost always the prevalence of identified autism. Which is to say, it’s a count of who has a diagnosis already. If someone isn’t diagnosed, s/he isn’t counted in these sorts of prevalence reports. So, we can test the idea that (a) autism is obvious and (b) the understanding of what autism is doesn’t change.

So let’s look at data for Danes born in 1990-92. Autism prevalence vs age. If autism is obvious and the definition isn’t changing, this should be a level line. Or, let’s say, after an initial increase as kids are diagnosed, this will be a flat line. Right? Oh, you know with this much of a lead in, this isn’t going to be the case.


The line is not just a guide to the eye. It’s a fit. For some reason, these data are almost a straight line. Autism prevalence increased as the kids aged.

edit to add: in case you prefer bar graphs I’ve added one (for both, click to enlarge).


Consider just the last two points: age 15 and age 20. Autism prevalence went from 73.4 to 109.7 per 10,000. That’s like a 50% increase in 5 years! Is that an epidemic? No. Those autistics were always there. Just uncounted. And they were 15 years old. They were missed.

There are a few ways to look at the increase in autism prevalence in Denmark, the US and elsewhere:

1) The rates reported are accurate counts of how much of our population is autistic and, thus, represent a real increase.
2) There are social influences like shifts in our understanding of what is autism and how well we can diagnose autism and these are behind the increase.
3) Much of the increase is socially driven. It could be all. We can’t rule out that some is a real increase.

It’s not hard to see that (3) fits the data.

People pushing the idea of an autism epidemic don’t even accept that social factors and “real” increases are on the same footing. No, they promote the idea that social influences are a “denial” mechanism. But the fact is, there are data showing that social influences have had a huge impact on autism prevalence. The only data pointing to a “real” increase are those linking increased risk of older parents with increasing age of parents to the autism prevalence (estimated to account for 4-10% of the observed increase in California). This is both a “real” increase and a socially driven increase, by the way.

For what it’s worth, “real” isn’t in “scare quotes”. Some people use “real” to mean “a secular increase in autism prevalence. An actual increase in the fraction of autistics born.” Social factors are real, making real changes in autism prevalence.

Lastly, people will say, “autism is a crisis! If you don’t acknowledge the epidemic you aren’t taking this seriously!” Crisis: a difficult or dangerous situation that needs serious attention. Crisis does not equate to epidemic.

The fact that autistics are being missed *is* a crisis. It is something I take seriously and feel “needs serious attention”. Also, the idea that there could be an increase in autism prevalence is a very serious question getting very serious attention.

Are those promoting the “vaccine epidemic” idea actually treating autism as a crisis? No, they are not. Avoiding the question of undiagnosed autistics is denialism and is hurting our communities.

I know this article is pounding nails into a coffin that is already not only nailed shut, but arc-welded shut and then encased in concrete. Beyond that, the acceptance for the thimerosal causation idea–which was never a majority idea among parents– has waned, dramatically. New parents know their kids were not exposed to thimerosal. That, more than anything, killed the hypothesis within the autism parent community. Parents aren’t chelating their kids any more. The idea is dead. Sure there’s a hard core of believers still talking about it. And, more, they use this idea to scare others about vaccines.

Why talk about it then? For those few people who do get suck into the autism-as-mercury-poisoning world today. It’s still a very damaging notion, leading parents to lead lives of guilt and to become a ready market for the faux-therapies that have been built around the thimerosal idea. They need to know–the idea has no merit, whatsoever. The data are as clear as data can get. Thimerosal in vaccines doesn’t cause autism.

By Matt Carey

Comment on “Potential Impact of DSM-5 Criteria on Autism Spectrum Disorder Prevalence Estimates”

25 Jan

One of the big topics of discussion in the past few years was the roll out of the DSM-5. The new criteria for what defines autism. One could find those saying “this is designed to undiagnose autistics with intellectual disability” as well as “this is designed to undiagnose autistics without intellectual disability” together with the multiple comments that “this is designed to obfuscate the “epidemic” of autism”.

A recent paper discusses this: Potential Impact of DSM-5 Criteria on Autism Spectrum Disorder Prevalence Estimates. The study looks at the CDC’s ADDM network–the same basis for the CDC autism prevalence estimates that come out every two years.

I haven’t read the full paper yet, but here’s the abstract:

IMPORTANCE The DSM-5 contains revised diagnostic criteria for autism spectrum disorder (ASD) from the DSM-IV-TR. Potential impacts of the new criteria on ASD prevalence are unclear.

OBJECTIVE To assess potential effects of the DSM-5 ASD criteria on ASD prevalence estimation by retrospectively applying the new criteria to population-based surveillance data collected for previous ASD prevalence estimation.

DESIGN, SETTING, AND PARTICIPANTS Cross-sectional, population-based ASD surveillance based on clinician review of coded behaviors documented in children’s medical and educational evaluations from 14 geographically defined areas in the United States participating in the Autism and Developmental Disabilities Monitoring (ADDM) Network in 2006 and 2008. This study included 8-year-old children living in ADDM Network study areas in 2006 or 2008, including 644 883 children under surveillance, of whom 6577 met surveillance ASD case status based on the DSM-IV-TR.

MAIN OUTCOMES AND MEASURES Proportion of children meeting ADDM Network ASD criteria based on the DSM-IV-TR who also met DSM-5 criteria; overall prevalence of ASD using DSM-5 criteria.

RESULTS Among the 6577 children classified by the ADDM Network as having ASD based on the DSM-IV-TR, 5339 (81.2%) met DSM-5 ASD criteria. This percentage was similar for boys and girls but higher for those with than without intellectual disability (86.6% and 72.5%, respectively; P <.001). A total of 304 children met DSM-5 ASD criteria but not current ADDM Network ASD case status. Based on these findings, ASD prevalence per 1000 for 2008 would have been 10.0 (95% CI, 9.6-10.3) using DSM-5 criteria compared with the reported prevalence based on DSM-IV-TR criteria of 11.3 (95% CI, 11.0-11.7).

CONCLUSIONS AND RELEVANCE Autism spectrum disorder prevalence estimates will likely be lower under DSM-5 than under DSM-IV-TR diagnostic criteria, although this effect could be tempered by future adaptation of diagnostic practices and documentation of behaviors to fit the new criteria.

Based on this, about 20% of those who would receive an ASD diagnosis under DSM-IV will not get one under DSM-5. The decrease was seen in both autistics with and without intellectual disability–with a larger decrease for those without ID. At the same time, some kids who were not previously identified as autistic would be under DSM-5.

By Matt Carey