The incidence of autism may be much higher than previously thought in the United States and throughout the world, a comprehensive six year study of autism in South Korea reported.
One in 38 children has autism; a jump from the previous estimation of 1 in 110 children. The South Korea study reported that many school kids have mild, undiagnosed autism.
The study searched for 7-12 year old children with autism spectrum disorder (ASD) among 55,000 kids in a South Korean community. The three main components of ASD are Asperger’s syndrome (the mildest form), autistic disorder, and pervasive developmental disorder. 2.6% of all children were diagnosed with autism in the South Korean city of Goyang. This is more than twice the rate normally reported.
“They came up with the startling number that one in 38 children has an autism spectrum disorder,” said Geraldine Dawson, PhD, chief science officer for Autism Speaks, the organization that ran the study. “This raises an important question for the U.S.: How many kids in the general education classroom actually have an ASD but not a diagnosis? These children may have gone under the radar.”
“This means that about two-thirds of children with ASD are in the community, unrecognized and untreated. Their lives can be improved significantly with early identification and intervention. It seems they have been there all along but were not counted in previous studies,” said study leader Young Shin Kim, MD at a news conference.
Experts say that this doesn’t mean the number of children with autism is rising, but that the study was more comprehensive. The Center for Disease Control reports autism prevalence by verifying records of existing cases diagnosed by health care and special education agencies. This leaves out many children whose parents or school never sought a diagnosis. In this study, the entire population of children was screened, including those who have never been flagged with a potential problem.
Two-thirds of the kids diagnosed with autistic disorder, and 90% of those with other ASD components, had average or superior intelligence.; proving that intellectual disability is not the core feature of autism.
The children newly identified are kids whose impairment is limited to the core features of autism, such as lack of communicating with other people in a socially acceptable way, restricted behaviors, or socialization skills.
So, how did so many children go undiagnosed?
“It may be a lack of professionals in a community, or some families not seeking help due to cost, or it may be that some of these kids with ASD function quite well in the classroom setting,” Dawson says. “But the same child at noon hour with peers may be socially isolated and awkward in relationships with peers. Having good social skills is absolutely essential for being successful in the real world.”