Results of the MIND Institute’s baby sibling study have been published in the journal Pediatrics. The study puts the recurrence risk of autism at 19%. In other words, a family with one autistic child has, on average, a 19% chance that a subsequent child will be autistic. The study authors stress that the risk may be higher in some families and lower in others.
More discussion can be found in various news outlets carrying the story, including
The CDC’ autism prevalence estimates are probably the most quoted values. Not too long ago, the estimate was 1 in 166. Then 1 in 150. About a year ago, the estimate was revised to 1 in 100.
But, these numbers are estimates. And, more importantly, these estimates spam a wide range. Autism prevalence estimates vary by state and by ethnicity.
The state with the highest prevalence estimate is New Jersey. A team in New Jersey has analyzed the most recent data for the relationship on factors such as race/ethnicity and household income.
What did they find? Kids from high income families are twice as likely to get an autism designation as kids from less affluent areas.
The prevalence estimate in wealthy areas? 17 per 1000. Or 1 in 59.
Background: In 2007 the Centers for Disease Control and Prevention (CDC) reported a higher prevalence of autism spectrum disorder (ASD) in New Jersey, one of the wealthiest states in the United States, than in other surveillance regions. Objective: To examine the association of socioeconomic status (SES) with ASD prevalence. Methods: Information on eight-year-olds with ASD from four counties was abstracted from school and medical records. US Census 2000 provided population and median household income data. Results: 586 children with ASD were identified: autism prevalence was 10.2/1000, higher in boys than girls (16 vs. 4/1000); higher in white and Asian non-Hispanics than in black non-Hispanics and Hispanics (12.5, 14.0, 9.0, and 8.5/1000, respectively); and higher (17.2/1000 (95% CI 14.0-21.1)) in tracts with median income >US$90,000 than in tracts with median income ?US$30,000 (7.1 (95% CI 5.7-8.9)). Number of professional evaluations was higher, and age at diagnosis younger, in higher income tracts (p < .001), but both measures spanned a wide overlapping range in all SES levels. In multivariable models race/ethnicity did not predict ASD, but the prevalence ratio was 2.2 (95% CI 1.5-3.1) when comparing highest with lowest income tracts. Conclusions: In the US state of New Jersey, ASD prevalence is higher in wealthier census tracts, perhaps due to differential access to pediatric and developmental services.
With apologies for opening the subject of the Amish and autism once again, a recent paper in the journal Pediatrics explores vaccination and the Amish: Underimmunization in Ohio’s Amish: Parental Fears Are a Greater Obstacle Than Access to Care. Seth Mnookin has already discussed this at The Panic Virus at PLoS blogs in Anecdotal Amish-don’t-vaccinate claims disproved by fact-based study.
What is worrisome here is the fact that the nderimmunization amongst the Amish is resulting from parental fears. In a very different study from 2001, Haemophilus influenzae Type b Disease Among Amish Children in Pennsylvania: Reasons for Persistent Disease, most Amish parents who chose to not vaccinate were citing availability and convenience rather than fear as the reason.
To repeat–in 10 years the reasons for non-vaccinating amongst the Amish have changed from convenience to fear. We can’t say exactly why, but it seems quite plausible that the focus on autism, vaccines and the Amish could have played a role.
Given that the “Amish Anomaly” notion seems destined to linger on, I have written up another summary of the history and the facts of the story.
Dan Olmsted, now the owner of the Age of Autism, was once an editor for UPI. It was during his UPI time that he took on the autism/vaccine question that has since dominated his professional life. Back in 2005 he ran a series of stories which investigated the proposed link between autism and vaccines and, in specific, mercury. It was right around the time that the David Kirby/Lyn Redwood book “Evidence of Harm, Mercury in Vaccines and the Autism Epidemic: A Medical Controversy.” was published. This was likely the high water mark for the public’s acceptance of the vaccines-causation idea.
One of the ideas that Mr. Olmsted explored was that of the Amish. He started with the belief that they don’t vaccinate and set out to investigate whether this correlated with a lower autism prevalence. The idea of the Amish being a largely unvaccinated population was set out years earlier. David Kirby describes in Evidence of Harm how Lyn Redwood of SafeMinds discussed this in a presentation she made to congress in the year 2000.
Mr. Olmsted described his investigation starting in a piece, The Age of Autism: Mercury and the Amish . There was plenty of data even then which Mr. Olmsted could have considered which went against his hypothesis. Since then even more data has mounted against the idea.
And, yet, it persists. Often the “Amish don’t vaccinate and they don’t have autism” story pops up in internet discussions following news stories. Books have incorporated the idea. Of course it ends up in alternative medicine books on autism such as Kenneth Bock’s “Healing the New Childhood Epidemics: Autism, ADHD, Asthma, and Allergies”. The idea can be found in other boos as well, including “Timeless Secrets of Health and Rejuvenation” (2007) and “Cry for Health: Health: the Casualty of Modern Times” (2010). Again, this is a reason to revisit the debunking of this myth. The myth lives on, even in the face of facts.
In his 2005 UPI article, Mr. Olmsted started out with the assumption that the Amish don’t vaccinate. He set out to see if he could find autistics amongst the Amish, but didn’t look into the vaccination question with any depth:
So I turned to the 22,000 Amish in Lancaster County, Pa. I didn’t expect to find many, if any, vaccinated Amish: they have a religious exemption from the otherwise mandatory U.S. vaccination schedule.
As is well known now, the Amish do not have a religious exemption from the vaccine schedule. They do not have a religious prohibition against vaccination.
This was something Mr. Olmsted could easily have confirmed at the time. He might have checked the 1993 book Amish Society by John Andrew Hostetler (1993), in which he would have found the following statements about medicine:
“Some are more reluctant than others to accept immunization, but it is rare that an Amish person will cite a biblical text to object to a demonstrated medical need…” ….””If the Amish are slow to accept preventive measures, it doesn’t mean they religiously opposed to them…”
He might have made more than a cursory effort to contact people at the Clinic for Special Children in Strasburg, Pennsylvania. The Clinic, aside from serving special needs children (including autistics) runs vaccine clinics and has for some many years. In a piece explaining Mr. Olmsted’s failures, Mark Blaxill (also of the Age of Autism) explained that the Clinic did not return Mr. Olmsted’s phone call. No mention is given why Mr. Olmsted didn’t go to the clinic in his visits to Lancaster County
Had Mr. Olmsted done so, he would have known that this statement, again from his 2005 piece, was incorrect when he relied on a source who claimed a very low immunization rate:
That mother said a minority of younger Amish have begun getting their children vaccinated, though a local doctor who has treated thousands of Amish said the rate is still less than 1 percent.
He also made a misleading statement:
When German measles broke out among Amish in Pennsylvania in 1991, the CDC reported that just one of 51 pregnant women they studied had ever been vaccinated against it.
What is left vague in this statement was the fact that the 51 pregnant women were those who contracted German measles. Not surprising that those infected were largely unvaccinated. This doesn’t tell us what fraction of the whole population were vaccinated though, and is quite misleading.
One might wonder why Mr. Olmsted was not aware that the Amish participated in the eradication of Polio. Conversely, he might have questioned how polio was eradicated if the Amish did not vaccinate. Here is a March of Dimes photo from a 1959 vaccine clinic:
(from March of Dimes By David W. Rose, 2003)
An article available to Mr. Olmsted at the time of his 2005 article, Haemophilus influenzae Type b Disease Among Amish Children in Pennsylvania: Reasons for Persistent Disease, discussed the reasons why Amish parents did not vaccinate their children. While some did cite “religious or philosophical objections”, the majority said they would vaccinate if “vaccination were offered locally”:
Among Amish parents who did not vaccinate their children, only 25% (13 of 51) identified either religious or philosophical objections as a factor; 51% (26 of 51) reported that vaccinating was not a priority compared with other activities of daily life. Seventy-three percent (36 of 49) would vaccinate their children if vaccination were offered locally.
Since Mr. Olmsted’s original series, more data has come in refuting the “Amish Anomaly”. In 2006, a paper was published: Vaccination usage among an old-order Amish community in Illinois. Here is the abstract:
The Old-Order Amish have low rates of vaccination and are at increased risk for vaccine-preventable diseases. A written survey was mailed to all Amish households in the largest Amish community in Illinois inquiring about their vaccination status and that of their children. In this survey, the Amish do not universally reject vaccines, adequate vaccination coverage in Amish communities can be achieved, and Amish objections to vaccines might not be for religious reasons.
It is clear that the Amish do vaccinate and that it would have been simple for Mr. Olmsted to find accurate information about this at the time. It was certainly more difficult for Mr. Olmsted to ascertain what the prevalence of autism might be amongst the Amish. He made the assertion: ““there are only a few of them [autistic Amish] in the United States”.
Of the “few” Amish autistics Mr. Olmsted could find, six were being treated by Lawrence Leichtman. The children were unvaccinated but the doctor who reported them to Mr. Olmsted attributed their autism to high mercury levels. This is not surprising as Dr. Leichtman was one of the early alt-med practitioners working in autism, being part of the secretin fad of the 1990’s. One wonders if the “elevated mercury” levels in these children would stand up to tests performed by qualified medical toxicologists.
Another six autistic Amish, nearly under Mr. Olmsted’s nose at the time of his article, were being treated by the Clinic for Special Children in Lancaster, PA. Six children who had PDD or Autism were at that time being treated and written up for a study in the New England Journal of Medicine. They were missed by Mr. Olmsted. He has since argued that these children are syndromic and, thus, somehow not as relevant to his story. Those arguments aside, this was a clear miss for Mr. Olmsted.
In 2010, a study was presented at IMFAR: Prevalence Rates of Autism Spectrum Disorders Among the Old Order Amish
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.
A preliminary number of 1 in 271 is a far cry from “little” or no autism amongst the Amish. Given the limitations of working within a community like the Amish, it is surprisingly close to the 1 in 100 often cited as the autism prevalence estimate for the general U.S. population. The study was being prepared for submission when I checked with the lead author last fall. It will be interesting to see what the final number is obtained for the prevalence.
The IMFAR abstract was available, I believe, before Dan Olmsted’s book, The Age of Autism, went to press. Instead of including this information, he chose to paint autism as rare amongst the Amish using quotes he obtained in 2005 and unsupported statements like, “the most aggressive possible count of autistic Amish comes to fewer than 20 cases, which would give us a rate of no more than 1 in 10,000.” It seems unlikely, given the low sales figures, that The Age of Autism will be reprinted. If that should happen, I wonder if Mr. Olmsted will correct this misinformation. The facts are clearly against him. Certainly, his review of internet sources and cursory tour of Lancaster County hardly counts as “aggressive”.
The “Amish don’t vaccinate and don’t have autism” idea was never very well supported. Now, with more data in, it is just plain wrong. It would be a good and honorable thing for Mr. Olmsted himself to make this clear. Good. Honorable. And not going to happen.
More kids are being diagnosed autistic before age 3, at least if data from Massachusetts are generalizable. Early Diagnoses of Autism Spectrum Disorders in Massachusetts Birth Cohorts, 2001–2005 is a study in the journal Pediatrics. Of course the question will be posed: is this due to a shift to earlier ages of diagnosis, a true increase in the number of autistic children or a combination of the two.
Here is the abstract:
OBJECTIVE: We examined trends in autism spectrum disorder diagnoses by age 36 months (early diagnoses) and identified characteristics associated with early diagnoses.
METHODS: Massachusetts birth certificate and early-intervention program data were linked to identify infants born between 2001 and 2005 who were enrolled in early intervention and receiving autism-related services before age 36 months (through December 31, 2008). Trends in early autism spectrum disorders were examined using Cochran-Armitage trend tests. ?2 Statistics were used to compare distributions of selected characteristics for children with and without autism spectrum disorders. Multivariate logistic regression analyses were conducted to identify independent predictors of early diagnoses.
RESULTS: A total of 3013 children (77.5 per 10 000 study population births) were enrolled in early intervention for autism spectrum disorder by age 36 months. Autism spectrum disorder incidence increased from 56 per 10 000 infants among the 2001 birth cohort to 93 per 10 000 infants in 2005. Infants of mothers younger than 24 years of age, whose primary language was not English or who were foreign-born had lower odds of an early autism spectrum disorder diagnosis. Maternal age older than 30 years was associated with increased odds of an early autism spectrum disorder diagnosis. Odds of early autism spectrum disorders were 4.5 (95% confidence interval: 4.1–5.0) times higher for boys than girls.
CONCLUSIONS: Early autism spectrum disorder diagnoses are increasing in Massachusetts, reflecting the national trend observed among older children. Linkage of early-intervention program data with population-based vital statistics is valuable for monitoring autism spectrum disorder trends and planning developmental and educational service needs.
There is a lower “risk” for children of younger mothers and for children whose mothers do not use English as a primary language. This is consistent with many studies showing lower prevalence rates amongst disadvantaged groups.
The study above was interesting to me in that another study (which I can’t find as of yet on the Pediatrics website, but is in the news) has come out which shows Many Pediatricians Aren’t Testing Tots for Developmental Delays. According to the news story about the study,
MONDAY, June 27 (HealthDay News) — Although there’s been some improvement in the number of pediatricians checking toddlers for developmental delays, more than half still don’t routinely do so, a new study finds.
In 2002, just 23 percent of pediatricians reported always or almost always using one or more standardized developmental screening tools for infants and toddlers up to 35 months of age. By 2009, that number had risen to just under 48 percent, reported the study.
Pediatricians are doing more formal screening for developmental delays. This should push the average age of diagnoses even lower. But even as recently as 2009, only about half of pediatricians were doing these evaluations.
But, if there is any constant to the world of autism research news, it is that reports conflict. Just a few weeks ago, there was a bunch of stories about another Pediatrics study. For example: Not enough evidence for routine screening for autism, Canadian researchers say
Why not screen for autism routinely? Here’s a section of that story:
He expressed concern about the impact on parents and children if there is a false positive or false negative for autism spectrum disorder. The neurodevelopmental disorder has symptoms that can include differences in social and communication skills, motor skills and sometimes intellectual abilities.
“And with any test there is always a risk that you assume that the test will say you have autism when in fact you don’t have autism.”
Gorter is also quick to say that parents who have any concerns about their child’s functioning should seek help, and “if they do have a diagnosis of autism, to be on the wait list and get the services.”
“If a child is healthy, there are no parental concerns, is then screening better than not screening? That is the question.”
Well, this is one of those questions where I have an opinion. Yes, it is good to screen. I’ve dealt with both false positives and false negatives. Yes, both are difficult (to put it mildly). Leave aside the questions of how important getting early services may be: I think they are valuable. Also, over time I’ve read many accounts of parents being disillusioned by doctors who missed their children’s autism. This is a factor which I believe plays a significant role in much of what goes wrong in the autism parent communities. Pediatricians need to keep the trust of the parents, and early diagnosis is something which can go a long way towards achieving that goal.
A recent study by a team at Virginia Polytechnic Institute and State University has investigated the prevalence of autism within a university population. The paper, College students on the autism spectrum: Prevalence and associated problems, found a groups of students who met the diagnositic criteria for autism but were previously undiagnosed.
Here is the abstract:
As more young people are identified with autism spectrum diagnoses without co-occurring intellectual disability (i.e. high-functioning autism spectrum disorder; HFASD), it is imperative that we begin to study the needs of this population. We sought to gain a preliminary estimate of the scope of the problem and to examine psychiatric risks associated HFASD symptoms in university students. In a large sample (n = 667), we examined prevalence of ASD in students at a single university both diagnostically and dimensionally, and surveyed students on other behavioral and psychiatric problems. Dependent upon the ascertainment method, between .7 per cent and 1.9 per cent of college students could meet criteria for HFASD. Of special interest, none of the students who were found to meet diagnostic criteria (n = 5) formally for HFASD in this study had been previously diagnosed. From a dimensional perspective, those students scoring above the clinical threshold for symptoms of autism (n = 13) self-reported more problems with social anxiety than a matched comparison group of students with lower autism severity scores. In addition, symptoms of HFASD were significantly correlated with symptoms of social anxiety, as well as depression and aggression. Findings demonstrate the importance of screening for autism-related impairment among university student
Repeated for emphasis: “Of special interest, none of the students who were found to meet diagnostic criteria (n = 5) formally for HFASD in this study had been previously diagnosed.”
We have had much discussion here lately as to whether “symptoms of autism” equate to autism. If this is the case, the prevalence of autism amongst college students is on the high side of the Virginia Tech team’s estimates.
“From a dimensional perspective, those students scoring above the clinical threshold for symptoms of autism (n = 13) self-reported more problems with social anxiety than a matched comparison group of students with lower autism severity scores.”
A long-awaited study of autism prevalence in Korea came out today in the American Journal of Psychiatry. Most of the information we have about autism prevalence comes from the US, the UK and Europe, so many were looking at this as the “Korean Study”. It is that, and very much more.
The title of the study is Prevalence of Autism Spectrum Disorders in a Total Population Sample. I expect the study will be gathering quite a lot of press as the results are quite remarkable. For one thing, the autism prevalence is estimated at 2.64%. That’s right, over double the current estimates in the United States and the U.K.. For another thing, most of the prevalence is for autistic students who were previously unidentified and unsupported.
Unfortunately, I was unable to obtain permission to review the article pre-embargo for discussion here on the Left Brain/Right Brain blog. Instead, I wrote about this for the Autism Science Foundation as Prevalence of Autism Spectrum Disorders in a Total Population Sample. There you will find a more thorough review of the paper, complete with questions and answers with team member Roy Richard Grinker of George Washington University. The study was led by Dr. Young Shin Kim of Yale, and includes an international team:
Young Shin Kim, M.D., Ph.D., Bennett L. Leventhal, M.D., Yun-Joo Koh, Ph.D. , Eric Fombonne, M.D. Eugene Laska, Ph.D., Eun-Chung Lim, M.A., Keun-Ah Cheon, M.D., Ph.D. ,Soo-Jeong Kim, M.D., Young-Key Kim, M.D., HyunKyung Lee, M.A., Dong-Ho Song, M.D., Roy Richard Grinker, Ph.D.
Again, the full post can be found at the Autism Science Foundation blog.
I have written in the past that I will be attending IMFAR, the International Meeting For Autism Research. I will be supported by a stakeholder travel grant from the Autism Science Foundation, for which I am very grateful. What I haven’t mentioned before is that I was planning to attend IMFAR even before applying for the stakeholder grant. I’ve been planning on attending since I submitted an abstract.
That abstract was briefly, and mistakenly, posted online so I chose that time to acknowledge my identity. As it turns out the abstracts are still under embargo and, as such, I have pulled the remainder of this article. I will repost once the embargo is lifted.
IMFAR, the International Meeting For Autism Research will be held next month (May 12-14). The full scientific program is not up yet (with all the details about who is talking and when), but the preliminary program is online. You can see what sessions are focusing on and see who the keynote speakers are.
Here are some sessions which caught my eye:
Characterizing Cognition in Nonverbal Individuals with Autism: Innocation Assessment and Treatment (an invited symposium–i.e. the conference felt this was an important topic and specifically invited speakers to present their research)
Sex Differences and Females with Autism Spectrum Disorders
Interventions: Behavioral CAM and Psychopharmacology Treatments
In addition, a number of sessions have full or partial focus on adults:
Adults with Autism Spectrum Disorders: Challenges for Epidemiological and Outcome Research (another invited symposium)
Epidemiology: ASD Prevalence, Trends, and Adults with ASD
a poster session on Adults with Autism
Structural and Functional Brain Imaging in Older Children, Adolescents and Adults with ASD
If you missed it, let me draw your attention: there is a session that includes CAM–Complementary and Alternative Medicine
Poul Thorsen, a Danish scientist who worked on many subjects including autism prevalence, was indicted in the United States today, the Atlanta Business Chronical reports. The article, Dane indicted for defrauding CDC, notes:
A Danish man was indicted Wednesday on charges of wire fraud and money laundering for allegedly concocting a scheme to steal more than $1 million in autism research money from the Atlanta-based Centers for Disease Control and Prevention.
Poul Thorsen started his association with the CDC as a visiting researcher. Later he moved to Denmark and Aarhus University.
According to the news article, Mr. Thorsen was using his position to create fraudulent invoices, and got his university to pay funds into his personal accounts in the US.
Mr. Thorsen worked on many projects. Most pertinent to this blog are his group’s efforts on autism epidemiology. These include works on MMR vaccines and thimerosal (e.g. A population-based study of measles, mumps, and rubella vaccination and autism and Thimerosal and the occurrence of autism: negative ecological evidence from Danish population-based data )
No charge has been made about the quality of these research projects or the conclusions drawn. However vaccine-causation advocates have been promoting the Thorsen case as part of their efforts.
Make no mistake: if guilty Poul Thorsen has committed very serious crimes. As a taxpayer, of course I am upset that this man might have stolen taxpayer money. As an autism parent, I can say without reservation that if found guilty Mr. Thorsen should be sentenced to the maximum sentence. The damage to the reputation of the research community which has sought to answer the questions of vaccine causation. A million dollars is a lot of money, but it is small change compared to the potential damage that might be caused .
The Simons Foundation blog, SFARI, has always had a good quality of articles. Lately it appears to me that the frequency of articles has increased. One recent article hits a subject that has been a focus of mine for some time: prevalence estimates and how they vary by culture and geography. In Researchers track down autism rates across the globe Virginia Hughes talks to a number of researchers working on expanding autism prevalence studies to more countries. Outside of the US and the UK, autism prevalence studies are somewhat rare. Until fairly recently, prevalence estimates outside of the US and Europe were basically nonexistent.
Ms. Hughes starts with this introduction:
In urban areas of South Korea, some families of children with developmental delays will go to great lengths to avoid a diagnosis of chapae, or autism. They think of it as a genetic mark of shame on the entire family, and a major obstacle to all of their children’s chances of finding suitable spouses.
The stigma is so intense that many Korean clinicians intentionally misdiagnose these children with aechak changae, or reactive detachment disorder — social withdrawal that is caused by extreme parental abuse or neglect.
This won’t come as a surprise for those who have read Roy Richard Grinker’s Unstrange Minds, where Prof. Grinker explores how autism is viewed in various parts of the world, including South Korea.
Prof. Grinker is interviewed, as is his collaborator Dr. Young Shin Kim, and Dr. Eric Fombonne.
Autism prevelance work has been performed or is ongoing in Mexico, South Korea, Brazil, India, South Africa and Oman. Since autism isn’t diagnosed through a biological test, variations in culture can have a significant impact on the test methods.
Ms. Hughes notes:
Language and culture may also affect the way this research is carried out. For instance, the Korean language uses an extensive array of suffixes that denote the relationship between the speaker and the subject. South Korean children with autism have trouble using these social markers, but the Western-based standard tests of autism, such as the Autism Diagnostic Observation Schedule (ADOS), don’t test for this.
Similarly, Grinker points out, healthy children from non-Western cultures may display a trait that ADOS counts as a symptom of autism. In South Korea, for example, making eye contact with an adult is not socially appropriate.
“This is why it’s pretty useful to have [anthropologists] who can translate diagnostic instruments that were designed in one culture and used in another,” Grinker says.
Rather than cut and paste the entire article I will point you back to SFARI for the full piece. It is well worth reading.
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