Autism prevalence rises in US amid shift in demographics

Key takeaways:

• The prevalence of autism among 8-year-olds in the United States is one in 36.
• Rates of autism among Asian, Black and Hispanic children were 30% higher in 2020 than in 2018.

The prevalence of autism among 8-year-olds in the United States rose to approximately one in 36 children in 2020 amid a shift in the demographic makeup of children diagnosed with the condition, according to data published Thursday.

Data from the same network published in 2021 indicated that the prevalence of autism had risen to one in 44 children in 2018 amid progress in early detection. Other reports have also signaled a rise in diagnoses among children and teenagers.

A second report published Thursday found that 4-year-old children were less likely to be evaluated for or identified with autism in the early months of the COVID-19 pandemic in 2020 than a cohort of children 4 years earlier — a decrease that coincided with interruptions to health care services, the CDC noted.

“Disruptions due to the pandemic in the timely evaluation of children and delays in connecting children to the services and support they need could have long-lasting effects,” Karen Remley, MD, MPH, director of the CDC’s National Center on Birth Defects and Developmental Disabilities, said in a press release. “The data in this report can help communities better understand how the pandemic impacted early identification of autism in young children and anticipate future needs as these children get older.”

Researchers examined the prevalence and characteristics of autism in 4- and 8-year-old children in Arizona, Arkansas, California, Georgia, Maryland, Minnesota, Missouri, New Jersey, Tennessee, Utah and Wisconsin. They classified children as having autism if they ever received an autism diagnostic statement in an evaluation, a special education classification of autism eligibility or an autism International Classification of Diseases code.

In addition to the overall increase, the researchers found that the prevalence of autism among Asian, Black, and Hispanic children was at least 30% higher in 2020 than in 2018, and the prevalence among white children was 14.6% higher than in 2018.

“For the first time, the percentage of 8-year-old Asian or Pacific Islander (3.3%) Hispanic (3.2%) and Black (2.9%) children identified with autism was higher than among 8-year-old white children (2.4%),” the CDC noted in a release. “This is the opposite of racial and ethnic differences observed in previous ... reports for 8-year-olds. These shifts may reflect improved screening, awareness, and access to services among historically underserved groups.”

It was also the first time that the prevalence of autism among girls exceeded 1%, although it remained 3.8 times more prevalent among boys.

The researchers noted in one of their reports that the increase further highlights the need for enhanced infrastructure to provide “equitable diagnostic, treatment, and support services for all children” with autism.

“Similar to previous reporting periods, findings varied considerably across network sites, indicating the need for additional research to understand the nature of such differences and potentially apply successful identification strategies across states,” they wrote.

References:

Maenner MJ, et al. MMWR Morb Mortal Wkly Rep. 2023;doi:10.15585/mmwr.mm7202a1.

Shaw KA, et al. MMWR Morb Mortal Wkly Rep. 2023;doi:10.15585/mmwr.mm7201a1.