Study Says Autism Rate Higher Than Previously Thought

A study from the U.S. Centers for Disease Control and Prevention (CDC) has found that approximately 1 in 150 8-year-old children in multiple areas of the United States has been diagnosed with autism, a higher rate than previously estimated. The results prompted the CDC to describe autism as an "urgent public health issue."

It's unclear whether the study results — which translate to about 560,000 kids with autism — mean that the disorder is actually on the rise. Changes in data-gathering methods and the way autism is diagnosed may account for some or all of the increase over previous studies.

Autism is a disorder that can affect the way a child behaves, thinks, communicates, and interacts with others. Kids with autism are affected in different ways, and cases range widely in severity. Autism is more common in boys than girls, and it is usually diagnosed when a child is between 1 and 3 years old, although signs of the disorder can show up earlier.

There isn't one specific cause of autism. Research has focused on whether chemical imbalances, differences in the brain, genetics, or problems with the immune system play a role in causing the disorder.

Many other factors, such as food allergies and exposure to environmental toxins, have been considered as possible causes of autism, but no scientific evidence backs up those theories.

The CDC study, the first comprehensive report on autism rates among U.S. schoolchildren, was based on an analysis of school and medical records of kids who were 8 years old in 2000 and 2002. Previous surveys, which had estimated that 1 in 166 kids had autism, were based on less-complete studies, the CDC said.

What This Means to You

There is no cure for autism, but many resources can help support kids and families who are dealing with it.

Because kids develop at different rates, autism can be difficult to recognize and diagnose. Many kids who have autism develop fairly typically in the first year or two of life, and then begin to regress in the ways that they speak and socialize.

If you have concerns about your child during infancy and the early toddler months — particularly about the way your child's communication — be sure to closely document your observations and talk with your doctor promptly.

It's important to get an evaluation from a medical professional experienced in diagnosing and treating autism. There is no single diagnostic test, and the doctor may order a variety of tests to rule out other medical problems before making a diagnosis. Your child may be referred for further evaluation by a developmental pediatrician, a pediatric psychiatrist, or a pediatric neurologist. If there is something wrong, early intervention can help connect you to the resources your child and family need.

Reviewed by: Steven Dowshen, MD
Date reviewed: February 2007