More kids have autism, better diagnosis may be the reason
NEW YORK The government estimates that autism is becoming more common, but it’s only a small increase and some experts think it can be largely explained by better diagnosing of minority children.
About 1 in 59 U.S. children were identified as having autism in 2014, according to a Thursday report from the Centers for Disease Control and Prevention that focused on 8-yearold children. That’s up from 1 in 68 children in both 2010 and 2012.
White children are diagnosed with autism more often than black or Hispanic children, but the gap has closed dramatically. Autism used to be 20 per cent higher in white kids than black children, and that difference shrank to 10 per cent. The gap between white and Hispanic kids shrank from 50 per cent to 20 per cent.
That increased recognition in minority kids is likely a big reason for the overall increase, CDC researchers said.
The causes of autism aren’t well understood, and it’s not clear if other factors might also be at play — like, for example, more couples having babies later in life, said Thomas Frazier, chief science officer for the advocacy organization Autism Speaks.
“There’s still a ton of work to do to better understand why this is happening,” Frazier said of the increase.
There are no blood or biological tests for autism. It’s identified by making judgments about a child’s behaviour. Traditionally, autism was diagnosed only in kids with severe language and social impairments and unusual, repetitious behaviours. But the definition gradually expanded, and autism is now shorthand for a group of milder, related conditions.
The new CDC report is based on a tracking system in 11 states that focuses on 8-year-olds, because most cases are diagnosed by that age. The researchers check health and school records to see which children meet criteria for autism, even if they haven’t been formally diagnosed. It is one of three autism estimates by the CDC but is considered the most rigorous.
“It’s the gold standard,” said Alison Singer, president of the Autism Science Foundation, an autism advocacy and philanthropy organization.
The researchers gathered data from Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee and Wisconsin, casting a net that included about 300,000 children. The 1 in 59 was an average: It was as high as 1 in 34 in New Jersey, and as low as about 1 in 75 in five states.
Why the difference? Researchers said rates tend to be higher in states where they can access more records.
For years, the estimate was increasing in leaps and bounds, though it wasn’t clear why. A report released in 2007 put the estimate at 1 in 150, or the equivalent of about 1 child in every 5 or 6 classrooms. The new 1-in-59 figure translates to 1.7 per cent.