Prevalence and Disparities in the Detection of Autism Without Intellectual Disability

Area of Science:

• Neurodevelopmental Disorders
• Pediatric Health
• Public Health Surveillance

Background:

• Intellectual ability significantly influences functional outcomes in children with autism spectrum disorder (ASD).
• Accurate classification of ASD with and without intellectual disability (ID) is crucial for etiological research, service provision, and educational/health planning.
• Understanding prevalence trends and demographic disparities in ASD subtypes is essential for targeted interventions.

Purpose of the Study:

• To determine the prevalence of ASD with and without ID in 8-year-olds.
• To analyze trends in ASD prevalence with and without ID from 2000 to 2016.
• To identify demographic and socioeconomic disparities in ASD identification.

Main Methods:

• A cross-sectional study analyzed data from 2000-2016 ASD surveillance in the New York-New Jersey Metropolitan Area.
• Included 8-year-olds identified with ASD.
• Multivariable Poisson regression models were employed to assess trends and identify factors associated with ASD with ID (ASD-I) and ASD without ID (ASD-N).

Main Results:

• Overall, 4661 children had ASD; 32.3% were ASD-I and 59.3% were ASD-N.
• Prevalence of ASD-I and ASD-N increased 2-fold and 5-fold, respectively, from 2000-2016.
• Significant disparities were observed: Black children were less likely to be identified with ASD-N; children in affluent areas were more likely to be identified with ASD-N; ASD-I cases were more common in vulnerable areas.

Conclusions:

• Approximately one-third of children with ASD have co-occurring ID.
• Disparities in identifying ASD without ID exist among Black and Hispanic children and those in underserved areas.
• These findings highlight the need for equitable identification strategies and resource allocation for children with ASD.