New research suggests that the prevalence of autism is on the rise and it’s growing at a significantly faster clip among certain groups of kids.
Between 2007 and 2013, autism rates increased 73 percent among Hispanics and 44 percent among black children ages 3 to 5. At the same time, prevalence rose 25 percent for whites in that age range.
The findings come from a study published this month in the Journal of Autism and Developmental Disorders.
Autism spectrum disorder is a complicated condition, one with several contributing causes. Genes likely play a role, as do environmental factors like air pollution. Its symptoms are complex too, but generally include problems communicating, a sensitivity to touch and other sensory inputs, and digestive issues.
Walter Zahorodny, an associate professor of pediatrics at Rutgers, told Gizmodo that “We’ve been monitoring for approximately 20 years, and it’s clear that this increase is not all better monitoring,” referencing research showing around that 80 percent of the increase can be tied to outside factors like the environment.
“What these findings indicate is that we have yet to see a point where the autism rate has plateaued. It’s increasing, and when we look at this same group four years from now, we’ll probably see the extent to which this rate was an underestimate, too,” said Zahorodny.
The most recent figures from the CDC, which were released last year, indicate that 1 in 59 children have autism. The estimate is based on data collected on 8-year-olds in 2014 through the Autism and Developmental Disabilities Monitoring Network.
Since the start of the century, the government’s official estimate of autism prevalence has increased 150 percent.
“There is no doubt that autism prevalence has increased significantly over the past 10 to 20 years, and based on what we have seen from this larger, more recent dataset it will continue to increase among all race and ethnicity groups in the coming years,” said Walter Zahorodny, an autism researcher at Rutgers New Jersey Medical School who worked on the study.