Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2020

Abstract

Problem/Condition Autism spectrum disorder (ASD). Period Covered 2020. Description of System The Autism and Developmental Disabilities Monitoring (ADDM) Network is an active surveillance program that provides estimates of the prevalence of ASD among children aged 8 years. In 2020, there were 11 ADDM Network sites across the United States (Arizona, Arkansas, California, Georgia, Maryland, Minnesota, Missouri, New Jersey, Tennessee, Utah, and Wisconsin). To ascertain ASD among children aged 8 years, ADDM Network staff review and abstract developmental evaluations and records from community medical and educational service providers. A child met the case definition if their record documented 1) an ASD diagnostic statement in an evaluation, 2) a classification of ASD in special education, or 3) an ASD International Classification of Diseases (ICD) code. Results For 2020, across all 11 ADDM sites, ASD prevalence per 1,000 children aged 8 years ranged from 23.1 in Maryland to 44.9 in California. The overall ASD prevalence was 27.6 per 1,000 (one in 36) children aged 8 years and was 3.8 times as prevalent among boys as among girls (43.0 versus 11.4). Overall, ASD prevalence was lower among non-Hispanic White children (24.3) and children of two or more races (22.9) than among non-Hispanic Black or African American (Black), Hispanic, and non-Hispanic Asian or Pacific Islander (A/PI) children (29.3, 31.6, and 33.4 respectively). ASD prevalence among non-Hispanic American Indian or Alaska Native (AI/AN) children (26.5) was similar to that of other racial and ethnic groups. ASD prevalence was associated with lower household income at three sites, with no association at the other sites. Across sites, the ASD prevalence per 1,000 children aged 8 years based exclusively on documented ASD diagnostic statements was 20.6 (range = 17.1 in Wisconsin to 35.4 in California). Of the 6,245 children who met the ASD case definition, 74.7% had a documented diagnostic statement of ASD, 65.2% had a documented ASD special education classification, 71.6% had a documented ASD ICD code, and 37.4% had all three types of ASD indicators. The median age of earliest known ASD diagnosis was 49 months and ranged from 36 months in California to 59 months in Minnesota. Among the 4,165 (66.7%) children with ASD with information on cognitive ability, 37.9% were classified as having an intellectual disability. Intellectual disability was present among 50.8% of Black, 41.5% of A/PI, 37.8% of two or more races, 34.9% of Hispanic, 34.8% of AI/AN, and 31.8% of White children with ASD. Overall, children with intellectual disability had earlier median ages of ASD diagnosis (43 months) than those without intellectual disability (53 months). Interpretation For 2020, one in 36 children aged 8 years (approximately 4% of boys and 1% of girls) was estimated to have ASD. These estimates a...

Epigenetic Gene-Regulatory Loci in Alu Elements Associated with Autism Susceptibility in the Prefrontal Cortex of ASD

“…Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by behavioral deficits based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria, including deficits in social interactions and communication, restricted interests, and repetitive behaviors [ 1 ]. According to the Centers for Disease Control and Prevention (CDC), the prevalence of ASD increased dramatically in 2020, reaching approximately 1 in 36 children in the United States [ 2 ]. ASD is a complex condition, even though its root causes are still unknown.…”

Developmental profiles of young children with autism spectrum disorder and global developmental delay: A study with the GriffithsIIIscales

“…The etiological factors of ASD remain largely unknown (Masini et al, 2020;Yoon et al, 2020) and diagnostic markers are currently only behavioral (APA, 2013). According to the most updated United States data (Maenner et al, 2023), the average age of diagnosis is around 4 years, although early identification has increased over time (Shaw et al, 2021). A recent European survey of 2032 respondents across 14 European countries (Italy included) reports an average age of access to diagnostic services around 3 years (standard deviation of 17 months) and an average age of access to intervention services around 3.5 years, even though the first concerns usually arrive from parents and family members at around 18 months of age of the child later diagnosed with ASD (Bejarano-Martín et al, 2020).…”

“…In fact, children with ASD often experience additional developmental disorders (APA, 2013) and DSM 5-oriented diagnosis requires clinicians to specify if the ASD is accompanied by limitations in intellectual or language functioning and/or associated with other neurodevelopmental, mental or behavioral problems, such as Attention Deficit and Hyperactivity Disorder, language and communication disorders, obsessive-compulsive disorders, mood-anxiety disorders and epilepsy (APA, 2013;Jacob et al, 2019). In particular, Intellectual Disability (ID) is present in 37.9% of children with ASD aged 8 years with information on cognitive abilities in the United States (Maenner et al, 2023) and is one of the most disabling ASD co-occurring conditions, being associated with reduced adaptive functioning in children (Hedvall et al, 2013;Lee et al, 2022) and reduced quality of life of caregivers (Vaz et al, 2021). ID is a condition characterized by significant limitations in both intellectual functioning and adaptive behavior during childhood or adolescence (APA, 2013).…”

The prevalence and developmental course of auditory processing differences in autistic children

“…Characteristics of ASD present early in development and affect a range of behaviors including reduced eye contact, differences in verbal and nonverbal communication, repetitive motor movements, and heightened or reduced sensitivity to sensory input. In the United States, 1 in 36 children are estimated to have ASD, with boys 3.8 times more likely to be diagnosed than girls (Maenner et al, 2023). Early behavioral intervention has been shown effective in improving cognitive and behavioral outcomes in autistic children, highlighting the importance of early screening and detection (Dawson et al, 2010;Klintwall et al, 2015;Vietze & Lax, 2020).…”