Upper-income parents are more likely to have children with autism, according to a University of Wisconsin-Madison study. The findings suggest either the genetics or the lifestyles of wealthier people predispose their children to autism.
Researchers have spent decades trying to untangle the factors that cause autism. Since the 1940s, scientists noticed wealthier and more educated families had children with the disorder, said Maureen Durkin, a University of Wisconsin-Madison epidemiologist and lead author of the study.
But while some U.S. studies found a link, others done in Scandinavia found no connection between autism and social class, Durkin said. Yet those countries also have social safety nets and universal health care, so rich and poor alike can get to the doctor's office for a diagnosis of autism. That led some researchers to pursue whether there were differences in rates of diagnosis in the U.S., rather than rates of the underlying disorder.
The findings were published in PLoS One.