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Autism’s Prevalence Grows: ‘This Is a Big Problem’

March 29, 2012 at 12:00 AM EDT
The rate of autism diagnosis in American children continues to climb, according to a new Centers for Disease Control and Prevention report. Jeffrey Brown discusses the latest research into the group of disorders with CDC Director Dr. Thomas Frieden and the University of Rochester Medical Center's Dr. Susan Hyman.

JEFFREY BROWN: And we turn to the latest look at the increasing prevalence of autism through a new government report.

The number of children diagnosed with autism has been rising for several decades. Last year, Robert MacNeil examined many of the issues surrounding the group of disorders in a six-part series on the NewsHour.

He introduced us to his grandson Nick, who was first diagnosed when he was 2 years old.

ROBERT MACNEIL: Here you can see the disconnect between us.

Nick, which one is Thomas?

For me, the father of four children with four other grandchildren, seeking connection with Nick is a very poignant experience. To have a grandson who can tune me out or simply ignore me like this, make no eye contact for long stretches of time.

And I’m going to buy it for you as a present, okay?

Gives me a strange and painful feeling.

ALISON MACNEIL, daughter: Say thank you to grandpa.

NICK, grandson: Thank you to grandpa.

ALISON MACNEIL: Okay, there we go.


JEFFREY BROWN: Those symptoms are fairly typical of what some children with autism spectrum disorder deal with, difficulties with socializing and communication, as well as behavioral issues.

In a 2006 government study, an estimated one in 110 children were diagnosed with autism. But a new report out today by the Centers for Disease Control and Prevention found the prevalence of autism is higher still, with one in 88 children being diagnosed.

Among boys, the rate of autism disorders is one in 54, almost five times the rate for girls.

More now about these findings and the diagnosis of autism. Dr. Thomas Frieden is the director of the CDC, which produced the latest report. And Dr. Susan Hyman is the chair of the Autism Subcommittee of the American Academy of Pediatrics. She’s with the University of Rochester Medical Center.

Dr. Frieden, start with you.

One big question here is to what extent these numbers represent a major increase or more a result of better and increased diagnosis of autism. What do you read from this study?

DR. THOMAS FRIEDEN, director, Centers for Disease Control and Prevention: There are a few things that we know for certain and there are some things that we don’t know. And we always want to be up front about what we do and don’t know.

We know for certain that doctors are getting better at diagnosing autism. We also know for certain that communities are getting better providing services to children with autism and that at CDC we’ve gotten better at tracking all of the children in a community who may have been diagnosed or identified with autism.

So we know that some of the increase is certainly because we’re detecting more cases of autism. Whether that’s all of the increase or not, we simply don’t know. But we do know that there are many children with autism and that many of them need services and that diagnosis is often too late.

So whether this is a real increase or not is really secondary to saying that this is a big problem, lots of people are out there who need services and would benefit from services.

JEFFREY BROWN: And, Dr. Hyman, tell us a little bit more about the getting better at the diagnosis. It’s often referred to as a spectrum of symptoms. Help us understand that.

DR. SUSAN HYMAN, American Academy of Pediatrics: That’s correct.

The American Academy of Pediatrics recommended that pediatricians begin screening for autism in their patients in 2007. And screening requires looking for core symptoms of autism in very young children and continuing surveillance through school age.

The core symptoms relate to social give-and-take, using words and language for communication, and habitual behaviors or habits. So it is a spectrum of symptoms that are made more or less intense by other developmental disorders.

JEFFREY BROWN: And your sense is that in your world you’re better at diagnosing that and finding it early on?

DR. SUSAN HYMAN: We’re better because we’re looking. We’re better because we have more tools and we’re better because parents and teachers are more informed about identifying concerning symptoms earlier and earlier.

JEFFREY BROWN: Now, Dr. Frieden, you were talking about what we know and what we don’t know. Of course, this big question about the causes, causes — I mean, questions and debates about vaccinations, childhood vaccinations, environmental causes, genetic links.

What do you feel that can be said at this point?

DR. THOMAS FRIEDEN: Well, for one thing, we know that boys are nearly five times more likely to have autism than girls. There’s a huge difference there and a much higher rate among boys.

There’ve been 19 different studies that have looked at vaccines and autism, and none of them have found a link. In fact, this study that we’re producing today outlines the behavior and the fate of children who were born in 2000. So they were eight years old in 2008. Thimerosal, which some people had been concerned about being linked, was phased out of vaccines around 2000-2001.

So virtually all of the kids with autism in this study were most likely born and grew up without being exposed to thimerosal-containing vaccines. We don’t know the cause of autism. There are some factors associated with slight increases in autism, such as parental age. But those factors account for a very small proportion of cases.

Some combination of genes and the environment — we’re working hard to understand this more, and CDC has additional studies under way, the largest study in the country, to help us better understand the risk factors for autism, so that ultimately we could prevent it.

JEFFREY BROWN: Dr. Hyman, what would you add to that and fill in a little bit. What are the chief areas of research at this point?

DR. SUSAN HYMAN: The research that the CDC released today is critically important. It’s an epidemiologic study, so it’s really the framework of where to look and who to look in.

As Dr. Frieden said, the — until fairly recently, we thought that it was all about genes. And what we know now from some fairly recent research is that there are multiple genes that result in susceptibility, but environmental factors may turn these genes on and off at different times of development, so that it’s really — the epidemiologic studies are incredibly important in helping to frame where to look for these potential causes. And it’s multiple , because autism is not a singular diagnosis.

JEFFREY BROWN: There are some concerns raised that because children diagnosed with autism receive government support and some help, that that may contribute to the number of incidences that we’re seeing. What is your response to that?

DR. SUSAN HYMAN: So the question is, are the increased services around autism fueling more diagnosis?

And I think the studies like the one released today obviate that question by using specific diagnostic criteria. By using standard, validated screening tests and standard diagnostic approaches, we’re hoping that children who are diagnosed in Rochester and children diagnosed in Atlanta would be diagnosed with the same disorder and that the same criteria will help make the behavioral symptoms objective, because the — to be able to understand the biologic research that will ultimately lead to understanding cause, you need to have very careful diagnoses and consistency.

So your question is a really important one, both from a community planning standpoint, that you need accurate diagnosis, but also from a scientific standpoint.

JEFFREY BROWN: Well, Dr. Hyman, when you were referring to the screening process, are you saying that it should be done earlier and more often now? What do you want to see happen?

DR. SUSAN HYMAN: I’d like to see it done earlier.

The American Academy of Pediatrics recommends that screening take place at the 18- and 24-month visit and that, if possible, a 30-month screen, but that surveillance needs to be ongoing. Children who have typical intelligence may not present until later on, so that the most important thing for pediatricians to do is to do work with families and address their concerns and ask for those concerns, not wait for them to be volunteered.

JEFFREY BROWN: Dr. Frieden, what would you add to that, and what should parents — I guess what is the take-home to parents here that you want people to look for as early as possible?

DR. THOMAS FRIEDEN: The big picture is, we would like to make sure that every child is screened by 24 months, if they have autism, diagnosed by 36 months, and certainly in treatment by 48 months at the latest, and the earlier the better.

The bottom line for parents is, if you’re concerned, talk to your doctor or to your school or educational system to see whether your child should be assessed, and if they are assessed and found to be in need of services, to help get them the services that they need.

JEFFREY BROWN: And what is the next phase of research in terms of the prevalence numbers? This kind of thing that you have just released today, that goes on, that continues?

DR. THOMAS FRIEDEN: This is an ongoing study. We hope to release the next set by the end of next year or shortly thereafter.

We’re also going to younger age groups, so we can better understand that early diagnosis. So we’re beginning to study children four-years and younger. This is eight-years and younger, we can be sure to catch essentially all of the children with autism. But by also looking at the 4-and-unders, we can see about early diagnosis, and then our seed study is looking at what may be the causes of autism.

JEFFREY BROWN: All right, Dr. Thomas Frieden and Dr. Susan Hyman, thank you both very much.


DR. SUSAN HYMAN: Thank you.

JEFFREY BROWN: And you can watch our series on autism and find additional resources online at