U.S. Autism Estimates Rise by 30 Percent for Kids
Researchers say increase could be due to better diagnosis of the developmental disorder
"We really need to double down on our research into the environmental factors that work in some complex way with a child's genetics to increase the risk of autism," he said.
There also needs to be continued emphasis on earlier diagnosis of autism, added Dr. Melissa Nishawala, an assistant professor of child and adolescent psychiatry at the NYU School of Medicine and medical director of the Autism Spectrum Disorders Clinical and Research Program.
The new CDC study reports that most children are diagnosed with autism spectrum disorder after age 4, even though autism can be diagnosed as early as age 2.
"We need to push the frontier of diagnosis down to the earliest ages we can," Nishawala said. "The earlier we intervene, the more we can do to help nudge those brain pathways closer and closer to normal."
Autism experts believe the increase reported by the CDC is more likely due to improved detection of the disorder, particularly among children at the higher-functioning end of the autism spectrum.
For example, almost half of children identified with autism spectrum disorder in the new study have average or above average intellectual ability, compared to one-third of children a decade ago.
"We are looking much more carefully, and we are getting better at finding kids at both ends of the spectrum, in particular the higher end of the spectrum," Nishawala said.
At the same time, the experts believe there are likely even more kids with autism than reported, given possible flaws in the CDC's surveillance system.
"We feel the way the CDC measures autism misses cases and is under-representing it," Rosanoff said. "This new number doesn't surprise us, but we feel it still may not be an accurate reflection of the true public health challenge."
The CDC network tallies cases that come to the attention of physicians or educators, which then are verified through a comprehensive evaluation and a review of school and medical records. But if the case doesn't attract attention, or if records aren't available to substantiate the diagnosis of autism, then the network will overlook that case, Rosanoff said.