Early Manifestations of Autism Spectrum Disorder in Children with Congenital Heart Disease

Background: An estimated one in 59 children in the US has autism spectrum disorder (ASD). Children with congenital heart disease (CHD) are at increased risk for neurodevelopmental and neurobehavioral impairment. A previous study suggested a higher rate of failed ASD screening in children with CHD ² but the subsequent prevalence of confirmed ASD and age at diagnosis have not previously been reported in this population

Objectives: To determine the rate of ASD in children with congenital heart disease and the average age of diagnosis for children participating in a developmental outcomes program.

Methods: We examined the medical records of 422 children born between 2013 and 2016 who underwent surgery for CHD at Texas Children’s Hospital and are part of our Cardiac Developmental Outcomes Program (CDOP) clinic. We evaluated the proportion of children with positive ASD diagnoses as determined by clinical diagnostic evaluation that included the Childhood Autism Rating Scale 2-ST (CARS2-ST) or Autism Diagnostic Observation Schedule, 2nd Edition (ADOS-2). We examined demographic data as well as clinic visit information to determine age at diagnosis and frequency of visits. The rate of positive ASD diagnosis was compared to the previously reported CDC population estimate using Chi square analysis.

Results: Of 422 CDOP clinic patients, 26 (6%) were diagnosed with ASD. When compared to the reported population prevalence of ASD (16/1,000), the rate of positive ASD diagnosis was significantly higher in children with CHD (p<.001). The majority of those diagnosed with ASD were male (n = 22; 85%) and had at least one clinic visit before diagnosis (n=19, 73%). Some of the children (n=7, 27%) were diagnosed with ASD during their initial evaluation. The average age at ASD diagnosis for all children was 2.6 ± 0.96 years, compared to the national average of 4 years.

Conclusions: We have shown that children with CHD are at higher risk of ASD compared to the general population, and can be diagnosed earlier than traditionally reported in the setting of a dedicated neurodevelopmental outcomes clinic. Early diagnosis can facilitate receipt of evidence-based interventions that can lead to improved outcomes for children with ASD.