Q&A: Global rates of autism spectrum disorders

Dr. Damian Santomauro shares the latest findings on the global burden of autism.

This transcript has been lightly edited for clarity

What is autism spectrum disorder and why is this study important?

Autism, also known as autism spectrum disorder [ASD], is a complex developmental condition characterized by challenges in social interaction, communication, and also repetitive patterns of behaviors, interests, and activities. However, there is incredible diversity in how autism is characterized across the autistic community, and recognizing this is essential in providing tailored support. This study, conducted by the GDB 2021 Autism Spectrum Collaborators, is timely as it’s offering updated global estimates on the prevalence and health burden of autism, of the autism spectrum, emphasizing where attention for action is needed most.

What were the key findings of your research?

Globally, we estimated 1 in 127 individuals was autistic in 2021. We also estimated the difference in prevalence across the sexes was smaller than previously estimated, now coming closer to a ratio of about 2.1 to 1 globally, but still with more autistic males than autistic females. ASD was ranked within the top 10 causes of non-fatal health burden for children and adolescents under the age of 20 years.

However, the prevalence and health burden of autism persisted across the lifespan. These findings highlight the need for early detection and lifelong supportive services for autistic individuals.

Did you observe differences in ASD prevalence between regions and income groups?

We estimate the substantial differences in autism prevalence across the globe, ranging at the regional level between about 1 in every 163 individuals in tropical Latin America to about 1 in every 65 individuals in the high-income Asia Pacific region. And there are many factors contributing to this wide range, including varying exposures to risk factors, cultural variation, behavioral norms, or screening tools and diagnostic tools being used in those locations, and also how people are responding to these surveys, or whether they even choose to respond or participate in the survey in the first place.

Work is currently ongoing to explore ways to quantify and correct for these differences so we can paint the most accurate picture of the prevalence of autism globally.

How do you hope your research findings will be used?

Ultimately, we hope the findings from this study drive improvements in health care provision and policy planning, ensuring that autistic individuals receive the necessary support at every stage of their life. Beyond the numbers, our study calls for global response to better meet the diverse needs of autistic people, improving the quality of life worldwide. The persistence of autism’s health burden across a lifespan, including adulthood, demands a shift in how health systems respond to autism, emphasizing the importance of inclusive and accessible health care services.

We hope that this study provides a foundation for future research and policy interventions so the key stakeholders work to ensure that the unique needs of all autistic persons are met, and contributes to a better and more inclusive and understanding future.