New Study Finds Connection Between Lower Incomes and Higher Autism Rates
Autism rates are declining among wealthy white populations, while rising among poor whites and minorities, according to new research from investigators at the University of Colorado. The research, published in the Journal of Autism and Developmental Disorders, raises the possibility that parents in wealthier countries have successfully reduced environmental exposures that may lead to autism. At the same time, the study’s findings also highlight a serious racial and economic divide.
“While autism was once considered a condition that occurs mainly among whites of high socioeconomic status, these data suggest that the brunt of severe autism is now increasingly being borne by low-income families and ethnic minorities,” Dr. Cynthia Nevison, a lead author of the study, was quoted as saying in a report by Psychcentral.com.
According to Psych Central, the researchers analyzed 20 years of autism caseload counts from the California Department of Developmental Services, comparing data from 36 of the state’s most heavily populated counties. They found that autism prevalence increased steadily among all racial groups between birth years 1993 and 2000. Around 2000, autism prevalence in wealthy counties like Santa Clara and Monterey began to decline, while autism rates among whites in lower income counties increased significantly. By 2013, autism prevalence among whites in the lowest income counties doubled that of whites in the highest income counties.
The study also found that the autism rate among blacks has increased rapidly throughout California, representing the highest rates among any racial or ethnic groups at 1.8%. While some researchers believe this may be attributable to better screening and diagnosis, others believe environmental factors may be involved as well.
The University of Colorado researchers hope their study will encourage parents and legislators to focus on improved outreach and diagnosis.
“There is an urgent need to understand what wealthy California parents are doing or have access to that may be lowering their children’s risk,” the study concluded.