Childhood autism rates have ticked up once again, according to the latest data from Centers for Disease Control and Prevention.
According to the CDC, 1 in 36 (2.8%) 8-year-old children have been identified with autism spectrum disorder (ASD) – up from the previous 2018 estimate of 1 in 44 (2.3%).
The updated data come from 11 communities in the Autism and Developmental Disabilities Monitoring (ADDM) network and were published online in Morbidity and Mortality Weekly Report.
A separate report in the MMWR on 4-year-old children in the same 11 communities highlights the impact of COVID-19, showing disruptions in progress in early autism detection.
In the early months of the pandemic, 4-year-old children were less likely to have an evaluation or be identified with ASD than 8-year-old children when they were the same age. This coincides with interruptions in childcare and health care services during the COVID-19 pandemic.
“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, director of CDC’s National Center on Birth Defects and Developmental Disabilities, said in a statement.
“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,” Dr. Remley noted.
Shifting demographics
The latest data also show that ASD prevalence among Asian, Black, and Hispanic children was at least 30% higher in 2020 than in 2018, and ASD prevalence among White children was 14.6% higher than in 2018.
For the first time, according to the CDC, the percentage of 8-year-old Asian/Pacific Islander (3.3%), Hispanic (3.2%) and Black (2.9%) children identified with autism was higher than the percentage of 8-year-old White children (2.4%).
This is the opposite of racial and ethnic differences seen in previous ADDM reports for 8-year-olds. These shifts may reflect improved screening, awareness, and access to services among historically underserved groups, the CDC said.
Disparities for co-occurring intellectual disability have also persisted, with a higher percentage of Black children with autism identified with intellectual disability compared with White, Hispanic, or Asian/Pacific Islander children with autism. These differences could relate in part to access to services that diagnose and support children with autism, the CDC noted.
Overall, autism prevalence within the 11 ADDM communities was nearly four times higher for boys than girls. However, it’s the first time that the prevalence of autism among 8-year-old girls has topped 1%.
Community differences
Autism prevalence in the 11 ADDM communities ranged from 1 in 43 (2.3%) children in Maryland to 1 in 22 (4.5%) in California – variations that could be due to how communities identify children with autism.
This variability affords an opportunity to compare local policies and models for delivering diagnostic and interventional services that could enhance autism identification and provide more comprehensive support to people with autism, the CDC said.
A version of this article first appeared on Medscape.com.