In recent years, several reports have suggested that children with autism or other learning or behavioral developmental disabilities are more likely than typically developing children to have health conditions such as respiratory or gastrointestinal illnesses.
However the studies behind these reports were often small and showed inconsistent findings. Some of their methods had limitations. One of the biggest problems was that they didn’t adequately compare children with different types of developmental disabilities. Because of these limitations, many public health professionals and healthcare providers have been skeptical about whether children with autism or other behavioral developmental disabilities truly faced an elevated risk of other medical problems.
My colleagues and I wanted to help paint a clearer picture of this important public health issue. Our study, recently published in the journal Research in Developmental Disabilities, compared the medical conditions and healthcare needs of children with developmental disabilities with those of children without developmental disabilities. We also compared children with autism with those who had other developmental disabilities.
We assessed children included in the National Health Interview Surveys from 2006 to 2010. Households throughout the United States are randomly selected to participate in this annual survey. In households with children, one child is randomly selected to participate. Each child’s parent or other primary caregiver is interviewed in-person about the child’s health and development. Interviewers asked whether a doctor or other healthcare provider has ever told them the child has certain conditions including autism and several other developmental disabilities. We also ask if the child has a health condition such as asthma or has experienced other symptoms such as frequent diarrhea or colitis in the past year.
We included more than 41,000 children aged 3 to 17 years in the study. Of these, 5,469 had one or more of the following five developmental disabilities: autism, intellectual disability, attention deficit and hyperactivity disorder (ADHD), learning disability or other developmental delay.
As a group, these children had higher than expected rates of all of the medical conditions we studied. More specifically, they were:
* 1.8 times more likely than children without developmental disabilities to have ever had an asthma diagnosis,
* 1.6 times more likely to have had eczema or a skin allergy during the past year,
* 1.8 times more likely to have had a food allergy during the past year,
* 2.1 times more likely to have had three or more ear infections during the past year,
* 2.2 times more likely to have had frequent severe headaches or migraines during the past year, and
* 3.5 times more likely to have had frequent diarrhea or colitis during the past year.
These increased rates of health conditions held true even for children diagnosed with ADHD or learning disability, but not diagnosed with autism or intellectual disability.
However, one finding stood out in particular when we compared the developmental disability groups to each other: Children with autism were twice as likely as children with ADHD, learning disability or other developmental delay to have had frequent diarrhea or colitis during the past year. They were seven times more likely to have experienced these gastrointestinal problems than were children without any developmental disability.
This detailed assessment demonstrates that children with autism or many other types of developmental disabilities do, in fact, face an increased risk for many common health conditions. This, in turn, provides evidence that children with developmental disabilities require increased health services and specialist services, both for their core functional deficits and for health problems beyond their core developmental disabilities.
Reference: Schieve LA, Gonzales V, Boulet SL, Visser SN, Rice CE, Van Naarden-Braun K, Boyle CA. Concurrent medical conditions and health care use and needs among children with learning and behavioral developmental disabilities, National Health Interview Survey, 2006-2010. Res Dev Disabil. 2011;33:467-76.
If you’ve been following autism research in recent years, you have probably read—many times—that familial, or inherited, risk is seldom the whole picture. A few inherited genes are sufficient by themselves to cause autism. But most so-called “autism genes” only increase the risk that an infant will go on to develop this developmental disorder. As is the case in many complex diseases, it appears that autism often results from a combination of genetic susceptibility and environmental triggers.
This is where epigenetics comes in. Epigenetics is the study of the factors that control gene expression, and this control is mediated by chemicals that surround a gene’s DNA. Environmental epigenetics looks at how outside influences modify these epigenetic chemicals, or “markers,” and so affect genetic activity.
It is important to remember that scientists use the term “environment” to refer to much more than pollutants and other chemical exposures. Researchers use this term to refer to pretty much any influence beyond genetic mutation. Parental age at time of conception, for example, is an environmental influence associated with increased risk of autism, as are birth complications that involve oxygen deprivation to an infant’s brain.
Because epigenetics gives us a way to look at the interaction between genes and environment, it holds great potential for identifying ways to prevent or reduce the risk of autism. It may also help us develop medicines and other interventions that can target disabling symptoms. We have written about epigenetics previously on this blog (here and here). So in this answer, I’d like to focus on the progress reported at a recent meeting hosted by Autism Speaks.
The Environmental Epigenetics of Autism Spectrum Disorders symposium, held in Washington, D.C. on Dec. 8, was the first of its kind. The meeting brought together more than 30 leaders in autism neurobiology, genetics and epidemiology with investigators in the epigenetics of other complex disorders to promote cross-disciplinary collaborations and identify opportunities for future studies.
Rob Waterland, of Baylor College of Medicine in Texas, described epidemiological studies and animal research that suggested how maternal nutrition during pregnancy can affect epigenetic markers in the brain cells of offspring.
Julie Herbstman, of Columbia University, described research that associated epigenetic changes in umbilical cord blood with a mother’s exposure to air pollutants known as polycyclic aromatic hydrocarbons (PAHs). PAHs are already infamous for their association with cancer and heart disease.
Rosanna Weksberg, of the Hospital for Sick Kids in Toronto, discussed findings that suggest how assisted reproductive technology may lead to changes in epigenetically regulated gene expression. This was of particular interest because assisted reproduction has been associated with ASD. Taking this one step further, Michael Skinner, of Washington State University, discussed “transgenerational epigenetic disease” and described research suggesting that exposures during pregnancy produce epigenetic changes that are then inherited through subsequent generations.
Arthur Beaudet, of Baylor College of Medicine, discussed a gene mutation that controls availability of the amino acid carnitine. This genetic mutation has been found to be more prevalent among children with ASD than among non-affected children, suggesting that it might be related to some subtypes of autism. Further study is needed to follow up on the suggestion that dietary supplementation of carnitine might help individuals with ASD who have this mutation. Caution is needed, however. As Laura Schaevitz, of Tufts University in Massachusetts, pointed out, studies with animal models of autism suggest that dietary supplementation may produce only temporary improvements in symptoms of neurodevelopmental disorders.
So what does this all mean for research that aims to help those currently struggling with autism? The meeting participants agreed that the role of epigenetics in ASD holds great promise but remains understudied and insufficiently understood. For clearer answers, they called for more research examining epigenetic changes in brain tissues. This type of research depends on bequeathed postmortem brain tissue, and Autism Speaks Autism Tissue Program is one of the field’s most important repositories. (Find more information on becoming an ATP family here).
The field also needs large epidemiological studies looking at epigenetic markers in blood samples taken over the course of a lifetime. One such study is the Early Autism Risk Longitudinal Investigation (EARLI). More information on participating in EARLI can be found here.
Autism Speaks remains committed to supporting and guiding environmental epigenetics as a highly important area of research. We look forward to reporting further results in the coming year and years.
Got more questions? Send them to email@example.com.
Read more autism research news and perspective on the science page.
Posted by Simon Wallace, Autism Speaks director of scientific development for Europe
A fine mist was rolling in off the Atlantic as we made our way to the opening session of last week’s International Conference on Autism at the National University of Ireland, in Galway. Autism Speaks partnered with the university and the American Ireland Fund to put together a program that attracted not only researchers and clinicians, but also parents and policy makers. In all, more than 600 delegates attended this productive conference in the beautiful town of Galway, on Ireland’s west coast. The meeting was very much the brainchild of Autism Speaks board member Adrian Jones, a native of Ireland who now works for Goldman Sachs, in New York City. (You can view the full program here.)
We received a warm welcome from National University of Ireland President James Browne before spending two days hearing from international experts on advances in clinical practice, early intervention therapies and educational supports. As hoped, the presentations spanned the range of evidence-based practices in the United States and Europe. This included important information coming out of our own Autism Treatment Network (ATN) and other Autism Speaks programs and initiatives.
The morning presenters included Helen McConachie, of Newcastle University, who spoke about early intervention. Gillian Baird, a pediatrician from Guy’s Hospital in London, spoke as the chair of a committee that developed the United Kingdom’s clinical guidelines on referral and diagnosis of children and teenagers with autism. Also presenting was Cathy Lord, of Columbia University. Lord has been centrally involved in the upcoming revision of the Diagnostic and Statistical Manual (DSM), which physicians use to diagnose autism and related disorders. She explained that there would no longer be three separate diagnoses of autism, Asperger syndrome and pervasive developmental disorder-not otherwise specified (PDD-NOS). In the future, these will all be included under the unifying diagnosis of autism spectrum disorder (ASD). This is to avoid the persistent inconsistencies in how physicians assign children to one of the three subtypes.
Afternoon workshops included a presentation by our own Vice President for Translational Medicine Rob Ring, who spoke about the latest evidence for clinical use of medications for patients with autism. ATN Program Director Nancy Jones presented on the network’s ongoing work developing best practices and clinical guidelines.
Connie Kasari, of the University of California-Los Angeles, presented the second day’s keynote address, which focused on the large numbers of children with autism who receive services in schools—and the need for more research on the effectiveness of these services. Among the interesting research findings that Kasari described was the insight that young children with autism are more “socially connected” than we previously assumed. Around 20 percent, she explained, enjoy close friendships. Intriguingly, Kasari has observed that this social connectedness drops when schoolchildren with autism go out for recess.
For me, the highlight of the second day was a presentation by Jamie Reilly, who spoke of the challenges growing up with autism and how he went on to graduate from Ireland’s top-rated university and is now studying for a master’s degree in Belfast. Reilly spoke of the importance of his family—in particular how his “mum” taught him strategies for overcoming many of the difficulties he encountered. He also described how he occasionally continued to make mistakes—for example, saying “good riddance” rather than “goodbye” to one of his teachers at the end of a lesson. With his fantastic sense of humor, Reilly kept us laughing throughout his presentation.
We also heard from Jamie Reilly’s father—James Reilly, a physician and Ireland’s current minister of health. Minister Reilly’s emotional presentation spoke of his pride in his son’s achievements and respect for his wife’s determined efforts to ensure that Jamie had the opportunities he needed. The minister spoke of the need to provide the best evidence-based approaches to help children with autism reach their full potential. He also announced his ministry’s commitment to provide an additional $4 million over the next three years to improve diagnostic and early intervention services. Minister Reilly will also be creating a senior post to coordinate autism-related activities across Ireland’s departments of health and education.
As we wrapped up this fantastic conference, many delegates told us that this was the largest conference ever held at the university and one that stood out in the sheer number of stakeholders from the autism community. We left for our homes and workplaces with the feeling that we are on the “front foot” for the New Year, thanks to what we learned about the latest research and guidelines on evidence-based practices.
The interconnectedness of the brain and immune system has become a fascinating new field of research, not only in autism but also schizophrenia and even depression. It can be complex stuff. But neurobiologist Paul Patterson, PhD, has produced a remarkably accessible and enjoyable book that intertwines history, case studies and laboratory science. He calls his slim but insightful volume Infectious Behavior: Brain-Immune Connections in Autism, Schizophrenia and Depression.
Patterson is a professor of biological sciences at the California Institute of Technology and a research professor of neurological surgery at the University of Southern California’s Keck School of Medicine. Readers of this blog may find his name and research interests familiar. Last month, we published a guest post from one of our Weatherstone Fellows who is launching her autism research career in his lab. There, Patterson and his junior colleagues are using mouse models to study how some types of maternal infection during pregnancy can increase the risk that a future child will develop autism. The research holds the potential for both deepening understanding of autism and leading to ways that pregnancy-related risks might be reduced.
Infectious Behavior explores new discoveries about the powerful biochemical communication that takes place between the brain and the immune system (which protects our bodies from infections and cancer). Patterson lets us listen in on some of this brain-immune “crosstalk,” and he explains how it can provide clues to the nature and causes of common but mysterious disorders of brain development and function. Some of this research, he argues, may shed light on today’s autism epidemic.
“Paul Patterson is attempting to describe a new field of study of which he himself is the leading pioneer,” writes Robert Freedman, MD, chair of psychiatry at the University of Colorado. “[His] efforts are unique in that they bridge the basic science and clinical world in a way that no other researcher in this field has done.”
It’s an engaging and thought-provoking read for nonscientists and scientists alike.
…More autism research news and perspective on the Science page.
On Monday, January 9th, the Children’s Hospital of Philadelphia (CHOP) Center for Child Injury Prevention Studies announced a new study focused on how teens with high-functioning autism approach learning to drive. According to the study which surveyed almost 300 parents, two-thirds of teenagers with a high-functioning autism of legal driving age in their state are currently driving or plan to drive.
The CHOP study represents exciting news for the autism world! Not too long ago, many families were given little to no hope that their children would develop the skills that are necessary to drive. This is exciting news for the autism community, as an individual’s ability to drive can play a big role in establishing independence and increasing opportunities for participation in the community.
At the same time, there are a number of critical precautions that must be taken to ensure the safety of individuals with autism and the rest of the community when learning to drive. So while we embrace this exciting opportunity, we know that driving may not be an option for all living with autism.
In order to help our community explore the possibility of driving, Autism Speaks awarded a Family Services Community Grant to Beth Israel Deaconess Medical Center in 2011 for project called DriveAdvise. This project involves the development of a tool kit and an educational video that will help families decide whether an individual with ASD might consider driving. The video will interview individuals, family members, service providers and driving instructors and will provide us with an in-depth look into the factors that contribute to the potential and the skills necessary to help qualified drivers with high functioning autism get behind the wheel. Read more about the grant here.
Autism Speaks will provide the tool kit and video on our website as soon as this exciting project is completed.
by Lisa Goring, Autism Speaks Vice President, Family Services.
Alex, Jack, and Kirsten spend this entire episode talking about supports for people with autism who are attending college or university. This is the third and final part of our episodes at the ASA 2011 conference in Orlando. We talked with Marc Ellison of Marshall University’s disability services and Michael McManmon of the College Internship Program.