804 - Temporal Trends in Autism Spectrum Disorders and Its Co-Existence with Attention Deficit Hyperactivity Disorders

Publication Number: 804.6957

Darios Getahun, Department of Research & Evaluation, Kaiser Permanente Southern California; Department of Health Systems Science, Kaiser Permanente Bernard J. Tyson School of Medicine, Pasadena, CA, United States; Vicki Chiu, Department of Research & Evaluation, Kaiser Permanente Southern California, Pasadena, CA, United States; Theresa M. Im, Department of Research & Evaluation, Kaiser Permanente Southern California, Pasadena, CA, United States; Morgan Peltier, Hackensack Meridian School of Medicine, Neptune, NJ, United States

Background: Autism spectrum disorder (ASD) is a chronic neurodevelopmental disorder that has reached epidemic proportions in the United States and Europe. It is often a comorbid condition with other mental health disorders.

Objective: We aim to describe the recent trends in ASD and its co-existence with attention deficit hyperactivity disorder (ASD+ADHD) by child’s age, sex, and race-ethnicity categories in a large integrated healthcare system.

Design/Methods: A serial, cross-sectional study using Kaiser Permanente Southern California's electronic health records (2014-2023) on member children aged between 2 and 17 years was performed. ASD and ASD+ADHD cases, specialist-diagnosed and validated, were used to ascertain the outcome measures. The child’s race/ethnicity was determined from membership information. Percent changes between 2023 and 2014 were estimated. Adjusted relative risk (aRR) for incremental changes during the study period were computed.

Results: In this study of 8,280,258 children, the median age of the children was 10 years (Interquartile Range: 6-14). The prevalence of ASD among boys (from 1.60% in 2014 to 4.88% in 2023, p for trend <.001) and girls (from 0.36% in 2014 to 1.59% in 2023, p for trend <.001) increased during the study period. From 2014 to 2023, the risk-adjusted overall ASD (from 0.9% to 3.0%, p for trend = .001), ASD-only (0.7% to 2.5%, p for trend < .001), and ASD+ADHD (0.2% to 0.5%, p for trend < .001) rates increased. There was significant heterogeneity in trends by child’s race/ethnicity and sex (Table).

Conclusion(s): In this cross-sectional study, ASD-only and ASD+ADHD diagnoses in children increased significantly in both sexes and across all age and racial/ethnic groups during the study period. While the rising ASD-only and ASD+ADHD rates may reflect improved screening and diagnosis practices, the persistently high rates highlight the need for action to control the rising trends and reduce potential disparities through targeted intervention and promotion of health equity.

Table. Temporal Trend by Overall ASD, ASD Only, and ASD Co-Existence with ADHD (ASD+ADHD)
Abbreviations: RR, relative risk; CI, confidence interval; ASD, autism spectrum disorder; ADHD, attention deficit hyperactivity disorder; NH, non-Hispanic; PI, Pacific Islander
*Adjustments were made for the child’s age, sex, and median household income