Nav: Home

US autism rate unchanged in new CDC report

March 31, 2016

Researchers at the Johns Hopkins Bloomberg School of Public Health contributed to a new U.S. Centers for Disease Control and Prevention (CDC) report that finds the prevalence of autism spectrum disorder (ASD) largely unchanged from two years ago, at one in 68 children (or 1.46 percent). Boys were 4.5 times more likely to be identified with ASD than girls, an established trend. The rate is one in 42 among boys and one in 189 among girls.

ASD is a developmental disorder characterized by social and communication impairments, limited interest and repetitive behaviors. Early diagnosis and intervention are important to improving learning and skills. Rates have been rising since the 1960s, but researchers do not know how much of this rise is due to more children being diagnosed with ASD or if actual cases are increasing or a combination of both. The CDC's first prevalance report, which was released in 2007 and was based on 2000 and 2002 data, found that one in 150 children had ASD.

For this new report, the CDC collected data at 11 regional monitoring sites that are part of the Autism and Developmental Disabilities Monitoring (ADDM) Network in the following states: Arkansas, Arizona, Colorado, Georgia, Maryland, Missouri, New Jersey, North Carolina, South Carolina, Utah, and Wisconsin. The Maryland monitoring site is based at the Johns Hopkins Bloomberg School of Public Health.

"Although we did not observe a significant increase in the overall prevalence rates in the monitoring sites, we continue to see the disparity among racial and ethnic groups," says Dr. Li-Ching Lee, PhD, ScM, a psychiatric epidemiologist with the Bloomberg School's departments of Epidemiology and Mental Health, and the principal investigator for the Maryland-ADDM. "For example, in Maryland, we found that Hispanic children were less likely to be evaluated for developmental concerns and therefore less likely to be identified."

In Maryland, Lee notes, the vast majority of children (95 percent) identified with ASD had a developmental concern in their records by age three, but only 55 percent of them received a comprehensive evaluation by age three. "This lag may delay the timing for children with ASD to get diagnosed and receive needed services," Lee says.

The prevalence in Maryland was one in 55 children (1.82 percent) with one in 34 among boys and one in 161 among girls. The data were derived from health and special education records of children who were eight years old and living in Baltimore County in 2012.

This is the sixth report by the CDC's Autism and Developmental Disabilities Monitoring Network (ADDM), which has used the same surveillance methods for more than a decade. Estimated prevalence rates of ASD in the U.S. reported by previous data were:
  • one in 68 children in the 2014 report that looked at 2010 data
  • one in 88 children in the 2012 report that looked at 2008 data
  • one in 110 children in the 2009 report that looked at 2006 data
  • one in 150 children in the 2007 report that looked at 2000 and 2002 data

The researchers say it is too early to tell if the overall prevalence rate has stabilized because the numbers vary widely across ADDM communities. In communities where both health and education records were reviewed, the rates are from a low of 1.24% in parts of South Carolina to a high of 2.46% in parts of New Jersey.

Some trends in the latest CDC report data remain consistent, such as the greater likelihood of boys being diagnosed with ASD. Disparities by race/ethnicity in estimated ASD prevalence, the age of earliest comprehensive evaluation and presence of a previous ASD diagnosis or classification persist. Specifically, non-white children with ASD are being identified and evaluated at a later age than non-Hispanic white children. The majority of children identified with ASD by the ADDM Network (82 percent) had a previous ASD diagnosis or a special educational classification.

The causes of autism are not completely understood; studies show that both environment and genetics may play a role. There is no known cure, and no treatment or intervention has been proven to reduce the prevalence of ASD. The CDC recommends that parents track their child's development, act quickly and get their child screened if they have a concern. Free checklists and information for parents, physicians and child care providers are available at http://www.cdc.gov/ActEarly.
-end-
A full copy of the report, "Prevalence of Autism Spectrum Disorder - Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2012," is available on the CDC website here: http://www.cdc.gov/mmwr/volumes/65/ss/ss6503a1.htm

Johns Hopkins University Bloomberg School of Public Health

Related Autism Articles:

Brain protein mutation from child with autism causes autism-like behavioral change in mice
A de novo gene mutation that encodes a brain protein in a child with autism has been placed into the brains of mice.
Autism and theory of mind
Theory of mind, or the ability to represent other people's minds as distinct from one's own, can be difficult for people with autism.
Potential biomarker for autism
A study of young children with autism spectrum disorder published in JNeurosci reveals altered brain waves compared to typically developing children during a motor control task.
Autism and the smell of fear
Autism typically involves the inability to read social cues. We most often associate this with visual difficulty in interpreting facial expression, but new research at the Weizmann Institute of Science suggests that the sense of smell may also play a central role in autism.
Autism often associated with multiple new mutations
Most autism cases are in families with no previous history of the disorder.
State laws requiring autism coverage by private insurers led to increases in autism care
A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health has found that the enactment of state laws mandating coverage of autism spectrum disorder (ASD) was followed by sizable increases in insurer-covered ASD care and associated spending.
Autism's gender patterns
Having one child with autism is a well-known risk factor for having another one with the same disorder, but whether and how a sibling's gender influences this risk has remained largely unknown.
Pinpointing the origins of autism
The origins of autism remain mysterious. What areas of the brain are involved, and when do the first signs appear?
Genes, ozone, and autism
Exposure to ozone in the environment puts individuals with high levels of genetic variation at an even higher risk for developing autism than would be expected just by adding the two risk factors together, a new analysis shows.
New form of autism found
Autism spectrum disorders (ASD) affect around one percent of the world's population and are characterized by a range of difficulties in social interaction and communication.
More Autism News and Autism Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.