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Evaluation of a Records-Review Surveillance System Used to Determine the Prevalence of Autism Spectrum Disorders.

28 Jun

Perhaps the most well-known statistics about autism come from the CDC’s autism surveillance project. The Autism and Developmental Disabilities Monitoring (ADDM) Network is a multi-state operation coordinated by the CDC. Their reports are the source of the “1 in 166”, “1 in 150” and “1 in 100” numbers one hears in the press and elsewhere. The Netweork looks at children’s medical records, educational records and sometimes both sets of records and make determinations of which children have autism spectrum disorders (ASD’s). This allows the Network to monitor large numbers of children. But they don’t actually test each child,bringing up questions of how accurate are the prevalence numbers.

A CDC team has looked into this question (actually, questions) in a recent paper:

Evaluation of a Records-Review Surveillance System Used to Determine the Prevalence of Autism Spectrum Disorders.

Nonkin Avchen R, Wiggins LD, Devine O, Van Naarden Braun K, Rice C, Hobson NC, Schendel D, Yeargin-Allsopp M.

Developmental Disabilities Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, MS E-92, Atlanta, GA, 30333, USA, ravchen@cdc.gov.
Abstract

We conducted the first study that estimates the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a population-based autism spectrum disorders (ASD) surveillance system developed at the Centers for Disease Control and Prevention. The system employs a records-review methodology that yields ASD classification (case versus non-ASD case) and was compared with classification based on clinical examination. The study enrolled 177 children. Estimated specificity (0.96, [CI(.95) = 0.94, 0.99]), PPV (0.79 [CI(.95) = 0.66, 0.93]), and NPV (0.91 [CI(.95) = 0.87, 0.96]) were high. Sensitivity was lower (0.60 [CI(.95) = 0.45, 0.75]). Given diagnostic heterogeneity, and the broad array of ASD in the population, identifying children with ASD is challenging. Records-based surveillance yields a population-based estimate of ASD that is likely conservative

If you are looking for a glossary for these terms, one can be found here.

Sensitivity: Proportion of persons with condition who test positive

Specificity: Proportion of persons without condition who test negative.

Positive Predictive Value (PPV): Proportion of persons with positive test who have condition

Negative Predictive Value (NPV): Proportion of persons with negative test who do not have condition.

The methods used scored well in specificity, positive predictive value and negative predictive value. What was somewhat lacking is sensitivity–proportion of people who test positive. Many children with ASD’s are not captured by the methods used, suggesting that the estimates by the CDC are likely low.

What would be very interesting to see would be how the sensitivity has varied over time. Is part of the rise in the CDC’s autism prevalence estimates due to changes in sensitivity? Could the records be getting better as a result of the autism awareness campaigns over the last 10 or more years?

Social influence and the autism epidemic

28 May

Prof. Peter Bearman at the University of Columbia has spent considerable effort studying the autism data from the California Department of Developmental Services.

I wrote about Prof. Bearman’s paper Social influence and the autism epidemic before. It just popped up in pubmed.

When I checked the website for the center where Prof. Bearman’s team works, I found the press release from the paper:

Study: “Social influence” playing role in increased autism diagnoses

Social influence plays a substantial role in recent increases in autism diagnoses, according to a study in the March, 2010 issue of the American Journal of Sociology.

The study, by researchers from the Institute for Social and Economic Research at Columbia University, found that children living near a child who has been previously diagnosed with the disorder are far more likely to be diagnosed themselves in the following year. The proximity effect is not due to environmental factors or contagious agents, the study found. Rather, it is due mainly to parents learning about autism from other parents who have a child diagnosed with autism.

“We show that the likelihood of getting an autism diagnosis is clearly associated with person-to-person transmission of information,” said Peter Bearman, a sociologist who authored the study along with Ka-Yuet Liu and Marissa King. “Parents learn about autism and its symptoms; learn about doctors who are able to diagnose it; and learn how to navigate the process of obtaining a diagnosis and services from parents who have already been through the process with their own child.”

The researchers stress that the results do not mean that autism is not real or that it is overdiagnosed. “Our study doesn’t address the underlying cause of autism,” Dr. Bearman said. “We are describing the mechanism by which the number of diagnoses is increasing. It could be that the real incidence of the disorder is only now being uncovered. I think that is a reasonable message from this paper.”

In California, where this study was conducted, the number of autism cases handled by the California Department of Developmental Services increased 636 percent between 1987 and 2003.

The Columbia University team looked at data on over 300,000 children born between 1997 and 2003 throughout California. The team found that children who live within 250 meters of a child with autism have a 42 percent higher chance of being diagnosed with the disorder in the following year compared with children who do not live near a child with autism. Children who lived between 250 meters and 500 meters from a child with autism were 22 percent more likely to be diagnosed. The chance of being diagnosed decreases significantly the farther children live from another child with autism.

The study used several tests to determine whether these results could indeed be explained by a social influence effect, or if environmental toxicants or a virus are to blame. For example, the researchers looked at children who live close to each other, but on opposite sides of school district boundaries. These children are likely exposed to the same environmental conditions, but their parents likely belong to different social networks. The research shows that the proximity effect only exists when parents reside in the same school district. Children who live equally close to a child with autism but in another school district were no more likely to be diagnosed with the disorder than children who do not have a neighbor with autism.

The results also showed the proximity effect to be strongest among children on the milder side of the autism spectrum. That is also consistent with a social influence explanation, Dr. Bearman says. “Parents of severely disabled kids are more likely to recognize the disorder without needing input from social contacts, so we would expect to see a weaker social influence effect there, and that’s exactly what we found.”

The Strength of Social Influence

The data set used in the study allowed the researchers to judge just how strong the influence effect is compared to other factors that may be driving the epidemic. For example, previous studies have found a link between autism and parents’ ages. Parents today are having children later in life, and that could be causing autism cases to increase. Other studies have found that parents’ education plays a role as well. Better educated parents may be more likely to obtain a diagnosis for their children.

The Columbia team found that each of these factors plays a role in the epidemic, but the social influence phenomenon was the strongest. The researchers estimate that the proximity effect explains about 16 percent of the recent increases in autism diagnoses. Put another way, if no child lived within 500 meters of a child with autism, there would be a 16 percent reduction in autism diagnoses. That effect was stronger than the other factors tested. For example, the mother’s age explained about 11 percent of the increase. The mother’s education accounted for 9 percent.

The study was funded by the NIH Pioneer award for innovative health research.

What caught my eye was that last paragraph, where they note that 16% of the increase can be accounted for from this social influence phenomenon, but also that 11% was due to increased maternal age and maternal education accounts for another 9%.

This is in addition to diagnostic substitution, which accounts for about 25% of the increase in the CDDS client caseload.

One of the footnotes in the Social Influence paper also caught my eye:

The strong positive association of autism (during the period of increasing prevalence, 1992–2000) with socioeconomic status (King and Bearman 2009b), coupled with the increasingly negative socioeconomic status gradient for MR (arising from differential abortion rates for fetuses identified as chromosomally damaged through amniocentesis), has led to a relative stigma reversal and a consequent decline in the rate of MR diagnoses.

King and BEarman, 2009b is a “working paper” at Columbia University (“The Increased Prevalence of Autism.” Working paper. Columbia University, Paul F. Lazarsfeld Center for the Social Sciences.)

One feature that is very interesting in the paper is the how the level of “functioning” of the child relates to the social influence effect. The basic result of the paper is that when a family lives near another family with an autistic child, they are more likely to obtain CDDS services under the autism label. That effect is stronger for “high functioning” autism. To me, at least, this seemed counter intuitive. Here is a graph from the paper showing that the social influence effect means that a child with “high-functioning” autism is about 40% more likely to be registered with the CDDS if he/she lives close to a family with an autistic child.

The trend with proximity is very clear, as shown in the figure below. The probability of a child be registered with the CDDS with an autism label drops off very smoothly and clearly with distance to a family whose child was recently diagnosed. This is not seen for mental retardation.

As the authors point out:

Compared with children who are 501 meters–1 kilometer away from their nearest neighbor with autism, those in close proximity (1–250 meters) to a child with autism have a 42% higher chance of being diagnosed with autism in the subsequent year. Proximity of 201–500 meters increases the chance by 22%. In contrast, being farther away from a child with autism reduces the chance of a diagnosis.

I know this is a repeat in many respects. But I also have found this work to be very interesting and thought it worthwhile to bring up these points I didn’t discuss before.

Anne Dachel, Age of Autism Editor, makes remarkable claim

27 May

I was browsing the comments section of a seemingly innocuous story about autism – that early intervention might not be the universal panacea once thought – when I came across a comment from Anne Dachel, one of the leading ‘thinkers’ and editors behind the online anti-vaccine blog Age of Autism.

…I think a disorder that was unheard of 25 years ago…

I had to read it a couple of times to make sure I was seeing it right – I was – Anne Dachel believes autism was unheard of prior to 1985.

To say this is a remarkable claim is being overly fair to Dachel. Its one of those claims that is regularly made by the Age of Autism team that leaves one’s jaw on one’s chest with the sheer audacity of either its boldness or stupidity. It reminds one of John Best’s claim that autism was unheard of in China prior to 1999. Another rampant piece of stupidity.

As previously noted, Dachel writes for Age of Autism. I’ll leave you to form your own conclusions as to the accuracy of their blogging based on their Editors own bizarre beliefs about autism.

New study: many vaccines at once OK for kids

24 May

A new study from Pediatrics has come to the conclusion that:

Timely vaccination during infancy has no adverse effect on neuropsychological outcomes 7 to 10 years later. These data may reassure parents who are concerned that children receive too many vaccines too soon

Lead researcher Michael J. Smith said:

Our study shows that there is only a downside to delaying vaccines, and that is an increased susceptibility to potentially deadly infectious diseases,

…

We hope these findings will encourage more parents to vaccinate according to the American Academy of Pediatrics schedule, and reassure them that they’re making a safe choice when they do so.

Lets hope so. Today is a great day in the forward momentum of the confidence in vaccines now that Andrew Wakefield has been struck off and this latest study can only add yet more weight that no vaccine, no vaccine ingredient and no vaccine schedule has _ever_ been shown to cause autism either directly or indirectly.

This is the first time that a study such as this has been carried out:

…nobody had studied whether getting several vaccinations in a short time could have negative consequences, for instance by overloading the immune system, as many parents believe, according to Smith. He found that receiving as many as 10 different shots — including flu and whooping cough — had no impact.

And a CDC spokesman said:

Parents that are considering delaying vaccination should realize that there aren’t any specific benefits, and that they are putting their child at risk, and not only their child but also the community,

An excellent point. The benefits of vaccination are not just personal but societal. Those who refuse to vaccinate not only risk the personal well being of their children but the society they choose to live in.

Blogging IMFAR: Wrap-Up Notes

23 May

One of the things I wanted to do in blogging about IMFAR, was try to provide a bit of a wrap-up of my experience there in Philadelphia this year. Since it was my first time attending an IMFAR, and I really had no idea what to expect ahead of time, I figured it might be useful to jot down some overall notes retrospectively.

First and foremost, IMAR is a scientific meeting. There is no shortage of introduction to what is out there in current autism research. This began with Wednesday’s pre-meeting press conference. It was there, that the press would learn about several selected abstracts (apparently thought to be worthy of media attention): the University of Rochester’s (Dr. Susan Hyman) negative GFCF study results, the Kennedy Krieger Institute’s (Dr. Brian Freedman) debunking of the 80% divorce rate claim, and others such as, landmark genetic studies, infant sleep fMRI as potential early diagnostic tool in the future, and social/educational intervention strategies that demonstrate the importance of peer involvement. Each of the study authors presenting their work to the press, spent about 5-10 minutes giving the highlights and taking a few questions, but in reality, each presentation was barely a thumbnail sketch of what the research was about and perhaps a minute of discussion about potential real world significance of the findings. You can read more about the items that caught my attention in the press conference at Blogging IMFAR: Opening Press Conference and GFCF Diet Trial Results and Blogging IMFAR: Autism And Divorce Debunked, Among Others.

Following the day of the press conference, IMFAR was off and running, with full daily schedules of presentation sessions, and poster sessions running the majority of the day (one floor below where the presentation sessions were taking place). On one hand, I suppose the science presentations could seem fairly frustrating to many. Like the press conference, the oral sessions presentations are given on a fairly tight schedule, and often contain little more than an introduction, a few minutes of methodology discussion, a quick look at statistical results, and time for one or two questions – then it’s on to the next, which might even be something only very loosely related at times.

For a typical parent, I think it’s quite possible they’d find the whole format approaching “tedious-to-learning” much of the time, with only an occasionally very interesting or very well-presented piece of research. Don’t get me wrong, I wouldn’t want detract from the likely importance of researchers having an open venue to share ideas with each other, but for me, there are only so many shotgun presentations you can listen to, or posters you can look at in one day.

On the other hand, IMFAR is a place where it seems ridiculously easy to get the big picture quickly, and even talk with expert researchers in the field of autism science if you are so inclined. It’s hard not to catch the what of what’s currently taking place in autism research world, as it’s everywhere – in the program, in the posters, and in the discussions. As an example, if one wanted to learn what’s taking place in autism research that’s using brain imaging, whether looking at language response and differences in infant siblings of autistic children, or looking at the potential impact of some specific intervention on brain funtion, researchers studying just those kinds of things are at IMFAR presenting and discussing their research. From what I saw, one can attend the relevant presentations, and then visit with researchers later on – I saw this occur on several occasions, with researchers like Eric Courchesne (University of California, San Diego). “Accessibile” is word that is probably a pretty good way to sum up my general thoughts on the science at IMFAR. while the format can seem very dry, especially to someone like myself (who didn’t arrive with a specific scientific field of interest that I was dying to scout out), the science and the researchers do seem really accessible.

Which brings me to what I thought was an important impression of IMFAR. The scientists really do seem accessible – willing to spend time for those with quesitons, and willing to provide explanation and lay translation where appropriate. On the first full day at IMFAR, I have to admit that I really didn’t know where to start. How was I ever going to explore all the science, and then distill that down to something digestible in size, yet explanatory of the trends in autism science? I was so fortunate to have the opportunity to meet with Dr. David Mandell. Besides being a local Philadelphia researcher, he was the Scientific Program Chair for IMFAR this year. And I could not be more appreciative of the time he gave to me (and LBRB readers), in sitting down to explain the trends in autism research at IMFAR – and he’s probably one of the best possible people to see and understand those trends, as he read every one of nearly a thousand abstracts accepted at IMFAR this year. If you want the inside scoop on the science at IMFAR, as well as an opportunity to simply get to know the thoughtful Dr. Mandell a little better, it can be found at Blogging IMFAR: Excerpts Of An Interview With David Mandell, ScD.

Speaking of thoughtful autism researchers, while at IMFAR, I literally ran into (interrupting his cell phone conversation while on an escalator) Dr. Roy Richard Grinker, professor of anthropology and human sciences, autism epdemiologist, author of the book “Unstrange Minds”, and wouldn’t you know it, a jazz pianist and marathoner too! Dr. Grinker was gracious enough to sit down with me for coffee, and share a little more about why he was at IMFAR with LBRB readers. You can read the interview at Blogging IMFAR: Meet Roy Richard Grinker.

At this point in my notes, we’ve arrived at midday Friday. And it as midday Friday when I see what I consider the most interesting science. As a recipient of a travel/attendance grant (that partially funded my trip to IMFAR) from the Autism Science Foundation, I was also invited to attend their “Science and Sandwiches” luncheon. It might be tempting to think I was attracted simply for the free food, but the sad truth was, that I had eaten a very late breakfast and wasn’t even hungry at the time of the luncheon. During the “Science and Sandwiches” lunch, each of 6 pre-doctoral students presented an overview of their research plans. These are pre-doctoral students who applied, and in turn, the Autism Science Foundation selected, to fund their research directly. They all seemed fairly interesting and unique, ranging from researching social conversation rules among ASD kids and infant emotions measurement, to very specific mouse model genetics/pharmacological experiments, to epidemiology. Yes, epidemiology. It might seem surprising that a young autism science advocacy org like ASF, or anyone for that matter, would fund epidemiology. I can’t help but think that field is already maturing to some degree in the U.S. I thought to myself, other than potential minority underrepresenation, what kind of breakthroughs in scientific understanding could we really get from epidemiology in the U.S.? I mean, we already know that we’re probably finally very close to what is a pretty stable 1 in 100. What else is there?

That’s when we were introduced to Matthew Maenner. Maenner is a pre-doctoral student of the University of Wisconsin, Madison (working under the mentorship of Dr. Maureen Durkin), who proposed, what to me, looks like a very interesting take on autism epidemiology with his research titled, “Phenotypic Heterogeneity and Early Identification of ASD in the United States”. He asked the luncheon group (of what looked like about 60 attendees), about how many possible combinations of the individual DSM diagnostic criterion can result in an ASD diagnosis. You know, if one looks at all the possible permutations of: “(I) A total of six (or more) items from (A), (B), and (C ), with at least two from (A), and one each from (B) and (C )” and the criteria for Asperger’s and PDD-NOS from the DSM IV-R, how many many combinations are there? It turns out there are 616 (I think I wrote that down correctly). He had a fascinating cloud-graph-type illustration of this (there’s probably a good technical term for this), that looked like a spiral galaxy – the point being that diagnostic criteria steer categorization to a shared core, but at the same time, there are numerous arms extending in several directions. He explained how he intended to look at the CDC’s ADDM data to begin to answer questions about the basis for the landscape of real world diagnoses compared to the actual possibilities described within the diagnostic criteria. Like a fool, I assumed that the ADDM data, like much of published autism epidemiology, tended to be focused on fairly simple prevalence, even dichotomous in nature (Autistic – yes/no, Asperger’s – yes/no, PDD-NOS – yes/no, X percent of all ASD’s = Autistic Disorder, etc.). Also, like a fool, I asked about him about this with something to the effect of, “In assuming the CDC’s ADDM data doesn’t have the resolution to go beyond diagnosis results, and into the individual combinations of criteria that result in those diagnoses, how are you going to even look at answering that question your research is about?”. He politely responds, explaining that, in fact, the CDC’s ADDM data does have this resolution. My assumption is way wrong, and this is an “Aha!” moment for me. We have tons of what is probably pretty good data available from the CDC, and it seems, to me, that no one has looked at it in quite this way before now.

So here’s my take on this ASF-funded doctoral student’s proposed research – he may be digging into something much more descriptive and potentially useful to the biological and educational sciences with respect to autism spectrum disorders, than has been done so previously (that I am aware of). If there’s epidemiology that can quantitatively describe the distribution of characteristics that result in ASD diagnoses, biological, and even educational research may have a leg up on being meaningful. As an example, suppose that this epidemiology determines that a certain percentage of ASD diagnoses include selection of the C – 4. “persistent preoccupation with parts of objects”. With real numbers, biological research may have a starting point to evaluate associations of differences in brain structure or function with respect to this characteristic. With real numbers, perhaps the success of specific educational strategies (that take advantage of this specific knowledge) can be meaningfully evaluated with more individualized approaches. Here’s the bottom line as I see it: Matthew Maenner is taking a solid step towards building understanding of the variation that occurs in autism spectrum disorders. It’s possible, if not likely, that his work could contribute to entirely new and much more individualized directions in other autism research. The days of any notion of singularity in etiologic origin of autism are long gone (in favor of complex combinations of numerous factors). Here’s a researcher who, in my opinion, understands that and will take steps towards building real understanding by looking at that distribution of variation. It wouldn’t surprise me in the least if “Matthew Maenner” is a name associated with the more interesting and useful autism epidemiology in the future.

So there you have it. That was my couple of days at IMFAR: an early look at some of the “newsworthy” science, an opportunity to learn much more about current trends in autism research from a hard-working scientist (the IMFAR Scientific Program Chair, Dr. David Mandell), a chance to sit down and chat with a very thoughtful researcher and author (Dr. Roy Richard Grinker), as well as first-hand look at some new research direction in graduate programs. All in all, it was a pretty interesting couple of days.

I’d also like to take just a minute and thank the Autism Science Foundation for partially, yet generously funding my travel (as a parent who blogs) to IMFAR. I had complete freedom to check out and write about whatever I wanted to, and it wouldn’t have been possible without their financial assistance.

(Disclosure: my attendance at IMFAR was funded in part, by a travel grant from the Autism Science Foundation.)

Blogging IMFAR: Meet Roy Richard Grinker

22 May

I had a neat opportunity here at IMFAR. Last night, as I was standing on the long escalator that traverses 3 floors from the IMFAR convention area to the lobby below, I glanced backwards to peek at the person behind me who was having a pretty animated conversation on a cell phone. His name tag read, “Roy Grinker”.

He noticed the glance (which was probably more like a bit of a stare, not too inconspicuous I suppose), and politely paused his conversation long enough for me to interrupt, introduce myself, and invite him to coffee this morning. He accepted.

Most LBRB readers will know Dr. Grinker as the author of “Unstrange Minds” and as a professor of anthropology and human sciences at The George Washington University. He continues to conduct autism research, and he has a role (that we’ll learn a little more about in a minute) at IMFAR too.

He arrives to coffee right on time, and is every bit as friendly as he appears in the pictures that often accompany articles about him online. He sits down to chat with me, and LBRB readers, so…

Meet Roy Richard Grinker, PhD

LBRB: Is it correct to say that your interest in autism research is with epidemiology?

RRG: Yes, my focus has been on epidemiology, but also on doing qualitative research on how culture influences the prevalence and recognition and management of developmental disabilities.

LBRB: Tell us a little more about what you mean by how culture influences those things. Is that willingness to diagnose, etc.?

RRG: Well, we don’t know very much, right now, about autism in other places in the world. It’s, at this point, an assumption that the onset, the core symptoms, and the course is universal. We don’t know, because we don’t have data from other cultures. For example, let alone phenotypes, we don’t have prevalence data for any country in the entire continent of Africa, any country in South America, any country in Asia other than Japan (that includes south Asia), and basically, in the international realm of autism research, it’s wide open.

LBRB: So what specifically brings you to IMFAR?

RGG: I came to the meeting this time primarily to meet and talk with people from other countries, where we don’t know much autism. And we have people here from all over the world. The reason that I’m wearing this button…

[He’s wearing a button with the IMFAR name and logo that reads, “DIVERSITY AMBASSADOR”]

…is to be part of IMFAR diversity.

LBRB: International reach?

RRG: International reach. It’s not so much like the American “diversity”, it is international diversity. We reach out to all the different countries, and as an example, there’s one autism researcher here from Nigeria. With this, he knows that I’m interested in meeting him. He can feel comfortable to just walk up and talk to me, or have coffee. There are a lot of people here from other countries who may not know anyone here.

LBRB: So you’re here for that purpose?

RRG: Yes, and to talk with other people at the meeting.

LBRB: Let’s switch gears a little. What about “American diversity”? What’s your take on the science about that, at a meeting like this?

RRG: In terms of diversity, I’m really inspired, inspired because, when a diversity committee meeting was held, there were about sixty people there. Most them are actually in the U.S., working in the U.S., and are interested in the barriers to care, and the obstacles to services within minority communities.

LBRB: That sounds like it could be interesting in and of itself.

RRG: We know that the age of diagnosis for minorities in the United States is significantly higher than the average age of diagnosis for non-minorities, and that means that they’re getting services later.

LBRB: What does the research science say about this?

RRG: Research supports the premise, one, that outcomes are better if interventions are earlier, and two, epidemiologic data supports the findings that African-American and Latino children are diagnosed later, and receive fewer services. There are data (but not published data) that I’m aware of, that show that even Latino children who are insured, don’t always get services as frequently as others. It could be that they were referred, but don’t take advantage of them, or perhaps there are other structural barricades; like they have insurance, but they also have three jobs, or they live far away from the services. We really don’t understand what all the barriers to uptake of care are, in minority populations. One of the projects I’m working on now is an NIMH-funded project to look at early identification of autism in two communities where there are virtually no autism services delivered.

[Dr. Grinker did provide a little more detail about one research project in southwest Florida, among migrant worker families, as well as a project in South Africa, from where he’d recently returned].

LBRB: So these are your real research interests?

RRG: There are three strands to my research. One strand is this work I’m doing in southwest Florida and South Africa. The second strand is the continued work on the prevalence of autism in South Korea, and we hope to report the results soon there, it’s been a long study – nearly thirty thousand children (the denominator in the sample). The third strand is my book writing – I love to write books.

LBRB: Tell us more about “Unstrange Minds”.

RRG: It just came out this week in Portuguese (so it’s available in Portugal and Brazil), and it really means a lot to me to be able to provide a message that people find uplifting. The thing is, that sometimes when people talk about my book, they focus on the argument about epidemic. And I think that’s important, and I spent a lot of time in my book going through the various reasons why autism diagnoses have increased. But, for me the most important part of the book is that it doesn’t present having a child with autism (or relative with autism) as a tragedy, or something that’s horrible and devastating. Rather, it’s a life experience which is distinctive, and can be incredibly rewarding. I take that positive perspective. I’m invited to give talks, occasionally. Sometimes I’ll give a talk somewhere, and I’ll ask why they invited me. Frequently the answer is, “because you’re not angry”. There are plenty of people out there who give public presentations that have to do with their anger – the anger that the community is not answering their questions, the anger that the services aren’t there, anger that their theory of causation isn’t taken seriously. I guess some people just want to hear somebody who’s got a more positive perspective, without being a Pollyanna, and I think that’s what I offered in the book.  To me, that’s the most rewarding thing.

LBRB: Can you give a personal scoop to Left Brain/Right Brain Readers? What do you like to do in your free time? Do you have any hobbies?

RRG: I have two hobbies. Jazz piano – and I’ve played jazz piano since I was very young. I played throughout college and graduate school. I played alumni parties, that sort of stuff. And I actually still work with a really talented guy in Washington, I’m still, you know, “taking lessons”. I started when I was four, I didn’t start jazz at four, but I probably started jazz when I was about 9 or 10. My parents’ apartment building was down the street from a jazz club.

[Grinker went on to explain that he was able to spend a little time at that jazz club (back in that day), and although I didn’t take down all of the names, he quickly rattled through a list of jazz greats (such as Dizzy Gillespie) he was able to meet in his youth].

What about hobby number two? He just finished (and finished well in) the Boston Marathon.

(Disclosure: my attendance at IMFAR was funded in part, by a travel grant from the Autism Science Foundation.)

Prevalence Rates of Autism Spectrum Disorders Among the Old Order Amish

17 May

One of the topics that comes up over and over online is “The Amish don’t vaccinate” and “the Amish don’t have autism”. Both statements are incorrect. The Amish have no religious prohibition against vaccination and they do have autism.

The question of autism amongst the Amish has been studied and is being presented at the IMFAR autism conference this week. The paper,
Prevalence Rates of Autism Spectrum Disorders Among the Old Order Amish, demonstrates a preliminary prevalence of 1 in 271 as the prevalence of autism amongst Amish children in two Amish communities: Holmes County, Ohio and Elkhart-Lagrange County, Indiana.

J. L. Robinson , Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL
L. Nations , Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL
N. Suslowitz , Center for Human Genetics Research, Vanderbilt University, Nashville, TN
M. L. Cuccaro , Human Genetics, University of Miami School of Medicine, Miami, FL
J. Haines , Center for Human Genetics Research, Vanderbilt University, Nashville, TN
M. Pericak-Vance , Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL
Background:

The prevalence rate of Autism Spectrum Disorders (ASD) appears to be steadily increasing. The latest report from the Center for Disease Control estimates the rate of ASD is 1 in 91 children (Kogan, 2009), up from 1 in 150 in 2007. Understanding the seeming changes in ASD prevalence require careful exploration of genetic and environmental factors. A method that has proven useful in dissecting the etiology of complex diseases is the study of isolated populations. One population isolate that has been studied extensively is the Amish, with well over 250 genetic studies. Expanding studies of autism to the Amish may provide important information about etiology. A crucial first step in this process is a feasibility study to determine ASD prevalence rates in this population.

Objectives:

This study presents preliminary data on the estimated prevalence of ASD among the Amish in two Amish dominant counties as part of a larger epidemiological study. All children between ages 3 to 21 in those counties will be screened for the presence of an ASD.

Methods:

Screening occurred in, two of the largest Amish communities in the United States. Trained clinicians ascertained door to door using a published Amish Directory as a guide. Families were approached and asked to participate in a brief interview regarding their children. Two primary screening instruments were used: the Social Communication Questionnaire (SCQ) and the DSM-IV-TR Checklist (a tool created by the authors). A Vaccination History and a brief family history including questions specific to the ASD phenotype were also taken. Children screening positive on either the SCQ or DSM-IV-TR Checklist were seen for a more comprehensive clinical evaluation by two licensed psychologists. This evaluation included the Autism Diagnostic Observational Schedule (ADOS) and Autism Diagnostic Interview (ADI).

Results:

From September 2008 to October 2009, 1899 Amish children were screened in the two Amish communities. A total of 25 children screened positive for ASD on either the SCQ or the DSM-IV-TR checklist. A total of 14 screened positive for ASD on both screeners. Of those 25 children, 14 were evaluated and seven children were confirmed as having a diagnosis of ASD using the ADI and/or ADOS, and clinical judgment. Interestingly, four of the seven only met ASD criteria on the ADOS but not the ADI. Three of the four who were not diagnosed by the ADI only missed criteria on the Behavioral Domain, which may be attributable to the reporting style of Amish caregivers.

Conclusions:

Preliminary data have identified the presence of ASD in the Amish community at a rate of approximately 1 in 271 children using standard ASD screening and diagnostic tools although some modifications may be in order. Further studies are underway to address the cultural norms and customs that may be playing a role in the reporting style of caregivers, as observed by the ADI. Accurate determination of the ASD phenotype in the Amish is a first step in the design of genetic studies of ASD in this population.

No Link Between Childhood Infections, Autism

10 May

One of the theories posited about autism causation is that childhood infections can result in autism. A recent study from the Arhus, Denmark, explores this by checking how often children are admitted to the hospital for infectious diseases. Given that maternal infections do appear to be associated with a greater risk of autism, the idea of childhood infections is worth considering. I would add that the attention to mitochondrial disorders and autism that was high in the past couple of years would also suggest this is a valuable area to consider.

Here is the abstract:

OBJECTIVE: To investigate the association between hospitalization for infection in the perinatal/neonatal period or childhood and the diagnosis of autism spectrum disorders (ASDs). DESIGN: A population-based cohort study. SETTING: Denmark. PARTICIPANTS: All children born in Denmark from January 1, 1980, through December 31, 2002, comprising a total of 1 418 152 children. EXPOSURE: Infection requiring hospitalization. MAIN OUTCOME MEASURE: The adjusted hazard ratio (HR) for ASDs among children hospitalized for infection compared with other children. RESULTS: A total of 7379 children were diagnosed as having ASDs. Children admitted to the hospital for any infectious disease displayed an increased rate of ASD diagnoses (HR, 1.38 [95% confidence interval, 1.31-1.45]). This association was found to be similar for infectious diseases of bacterial and viral origin. Furthermore, children admitted to the hospital for noninfectious disease also displayed an increased rate of ASD diagnoses (HR, 1.76 [95% confidence interval, 1.68-1.86]), and admissions for infection increased the rate of mental retardation (2.18 [2.06-2.31]). CONCLUSIONS: The association between hospitalization for infection and ASDs observed in this study does not suggest causality because a general association is observed across different infection groups. Also, the association is not specific for infection or for ASDs. We discuss a number of noncausal explanatory models.

Autistic children *are* admitted to the hospital for infectious diseases more often than the rest of the population. But, in general autistic children are admitted to the hospital more often than the rest of the population.

Bloomberg Businessweek discussed this paper in No Link Between Childhood Infections, Autism. They interviewed Dr. Andrew Zimmerman of the Kennedy Krieger Institute. Dr. Zimmerman concurred with the conclusions of the paper:

“Yes, there is an increased rate of hospitalization preceding the diagnosis of autism, but it doesn’t support a causal relationship between autism and infections,” Zimmerman said.

This is significant, in my view. Dr. Zimmerman is one of the doctors who treated Hannah Poling (the young girl whose case was conceded by the Department of Health and Human Resources in the vaccine court, sparking the public interest in the subject).

It is also worth noting that the study considered specific infections. From the Bloomberg/Newsweek story:

And the researchers could point to no particular infection that upped the risk.

They therefore conclude that childhood infections cannot be considered a cause of autism.

“We find the same relationship between hospitalization due to many different infections and autism,” noted lead study author Dr. Hjordis Osk Atladottir, of the departments of epidemiology and biostatistics at the Institute of Public Health, University of Aarhus in Denmark. “If there were a causal relationship, it should be present for specific infections and not provide such an overall pattern of association.”

Maternal Infection Requiring Hospitalization During Pregnancy and Autism Spectrum Disorders

4 May

One known possible environmental cause of autism is rubella infections in the mother during a pregnancy. This can lead to a condition called “Congenital Rubella Syndrome”. Many with CRS have very significant disabilities, including intellectual disablity and autism.

The epidemiological team at Aarhus, Denmark, has taken this one step further and looked at maternal infections in general. What they found was that viral infections in the first trimester and bacterial infections in the second trimester are associated with a roughly 3 times greater risk of autism for the child. The infections noted were severe enough to warrant hospitalization.

Maternal Infection Requiring Hospitalization During Pregnancy and Autism Spectrum Disorders.
Atladóttir HO, Thorsen P, Ostergaard L, Schendel DE, Lemcke S, Abdallah M, Parner ET.

Exposure to prenatal infection has been suggested to cause deficiencies in fetal neurodevelopment. In this study we included all children born in Denmark from 1980, through 2005. Diagnoses of autism spectrum disorders (ASDs) and maternal infection were obtained through nationwide registers. Data was analyzed using Cox proportional hazards regression. No association was found between any maternal infection and diagnosis of ASDs in the child when looking at the total period of pregnancy: adjusted hazard ratio = 1.14 (CI: 0.96-1.34). However, admission to hospital due to maternal viral infection in the first trimester and maternal bacterial infection in the second trimester were found to be associated with diagnosis of ASDs in the offspring, adjusted hazard ratio = 2.98 (CI: 1.29-7.15) and adjusted hazard ratio = 1.42 (CI: 1.08-1.87), respectively. Our results support prior hypotheses concerning early prenatal viral infection increasing the risk of ASDs.

Frontline excerpt: Ashland Oregon

22 Apr

The PBS show Frontline has an upcoming episode called “The Vaccine War”. They recently posted a video excerpt of the episode. In this segment they follow a public health worker in Ashland Oregon, a community with one of the highest vaccine refusal rates in the US.

So, how is that vaccine refusal working out in Ashland? That’s in Jackson County, Oregon. I’m not alone in asking that question. One of the founders of Generation Rescue asked the same question recently

The Centers for Disease Control reports that 15 percent of children in Jackson County, Ore., are unvaccinated, Handley said. Someone needs to find out how these kids look comparatively. “It’s in the pockets of the unvaccinated kids where the first truths may be found,” he said.

Ashland appears to have an even higher vaccine refusal rate than the rest of Jacknson County. From the Frontline press release:

With an estimated quarter of the town’s children entering kindergarten not fully immunized, Ashland is one of the least vaccinated places in America.

So, Jackson County has a refusal rate of about 15% and Ashland about 25%. Let’s see what the Ashland City Council has to say. Here is a proclamation from the City of Ashland proclaiming Autism Awareness month

PROCLAMATION

“AUTISM AWARENESS MONTH”

• Autism is a complex neurobiological condition that appears at birth or typically before age three and occurs in one out of every 150 births each year in the United States.
• Autism affects the areas in the brain that regulate pragmatics of speech and perceptions of others, affecting how people with autism assimilate and express verbal and non-verbal communication, and sensory processing.
• Oregon has one of the highest rates of autism in the United States, with the Oregon Department of Education reporting 1 in 98 students on the autism spectrum, and in Ashland, 1.1 percent of students have been diagnosed which is the highest rate in Jackson County.
• While there is no precisely identified cause and cure for autism, Autism Centers of Excellence and institutions for education such as Oregon Health & Science University, and the Southern Oregon University Masters in Special Education program offer hope for recovery, and treatments to lead a rich and fulfilling life.
• Early Intervention services such as those provided by Asante Early Childhood Development can alter the course for children living with autism and their families in their ability to interact and communicate not only wants and needs, but dreams and aspirations.
• Adults living with Autism and Asperger’s Syndrome can find a warm and welcoming home and community in Ashland.

NOW THEREFORE, the City Council and Mayor, on behalf of the citizens of Ashland, hereby proclaim the month of April 2008 as:

“AUTISM AWARENESS MONTH”

and call upon the citizens of the City of Ashland to observe the month by learning about people with autism, their strengths, abilities, and the programs which serve their needs.

Dated this 4th day of March, 2008.

Barbara Christensen, City Recorder
John W. Morrison, Mayor

Keep in mind that the above proclamation involves educational data, which are not the same as real autism prevalence. That is especially problematic in Oregon, which has a very vague criterion for an educational diagnosis. But, that said, Ashland (with a vaccine refusal rate of 25%) had 1.1% of their students with educational diagnoses of autism, the highest in Jackson County and higher than the Statewide average.

Again, education data are fairly weak to begin with, and Oregon has a very loose definition of “autism”. But, that said, there isn’t evidence in the educational data that vaccine refusal is helping Ashland avoid autism.
In other words it looks like vaccine refusal is not protecting Ashland from autism.

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