U.S. autism rates are higher than before, new study shows

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In a new study, researchers found the prevalence of autism spectrum disorder (ASD) among 11 surveillance sites as 1 in 54 among children aged 8 years in 2016 (or 1.85 percent).

This is a 10 percent increase from the most recent report two years ago when it was 1 in 59, and the highest prevalence since the CDC began tracking ASD in 2000.

Consistent with previous reports, boys were 4 to 5 times more likely to be identified with ASD than girls. The rate for ASD is 1 in 34 among boys (or 2.97%) and 1 in 145 among girls (or 0.69%).

The research was conducted by a team at the Johns Hopkins Bloomberg School of Public Health.

ASD is a developmental disorder characterized by social and communication impairments, along with limited interests and repetitive behaviors.

Early diagnosis and intervention are key to improving learning, communication, and other skills.

Rates have been rising dramatically in the past three decades, but researchers do not know how much of this rise is due to better detection or an increase in “true” cases or both.

Technical factors that may be contributing to an increase in ASD include increased awareness, screening, diagnostic services, treatment and intervention services, better documentation of ASD behaviors, and changes in diagnostic criteria.

To date, the causes of autism are not completely understood but studies show that both environment and genetics may play a role.

As in its prior report, the CDC collected data at 11 regional monitoring sites across the U.S. that are part of the Autism and Developmental Disabilities Monitoring (ADDM) Network.

The Maryland-ADDM monitoring site is based at the Johns Hopkins Bloomberg School of Public Health.

This is the seventh report by the ADDM Network, which has used the same surveillance methods each time.

Estimated prevalence rates of ASD in the U.S. reported by previous data were:

one in 59 children in the 2018 report based on 2014 data

one in 68 children in the 2016 report based on 2012 data

one in 68 children in the 2014 report based on 2010 data

one in 88 children in the 2012 report based on 2008 data

one in 110 children in the 2009 report based on 2006 data

one in 150 children in the 2007 report based on 2000 and 2002 data

The team says an ongoing and accurate estimate will help to develop realistic plans to support these children now, and later into their adolescence and adulthood.

In Maryland, the prevalence of ASD was 1 in 52 children: 1 in 33 for boys and 1 in 128 for girls.

The data were derived from health and special education records of children who were 8 years old and living in Baltimore County in 2016.

ASD can be diagnosed as early as 24 months of age. In Maryland, however, only 48.3 percent of children with ASD received a comprehensive evaluation by 36 months, and the median age at the earliest ASD diagnosis was 48 months.

The CDC recommends that parents track their child’s development, act quickly, and get their child screened if they have a concern.

One author of the study is Li-Ching Lee, Ph.D., ScM, a psychiatric epidemiologist.

The study is published in the CDC.

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