Prevalence and treatment of mental, behavioral, and developmental disorders in children with co-occurring autism spectrum disorder and attention-deficit/hyperactivity disorder: A population-based study

There is a lack of nationally representative studies examining the co-occurrence of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children. This study examines comorbid mental, behavioral, and developmental disorders (MBDDs) and associated treatment modalities for children with co-occurring ASD and ADHD. Cross-sectional analyses were conducted using data from the pooled 2016–2018 National Survey of Children's Health (sample n = 102,341). Nationally representative prevalences were estimated for sociodemographic variables, comorbidities, psychotropic medication, and behavioral treatment. We assessed multivariable associations between co-occurring ASD + ADHD and MBDDs, use of psychotropic medication, and receipt of behavioral treatment after adjustment for sociodemographic confounders. Compared to children with ASD without co-occurring ADHD, children with ASD + ADHD had higher prevalence of most MBDDs, including anxiety (AOR 4.03 [95% CI 2.77, 4.87]), depression (AOR 3.08 [95% CI 1.77, 5.36]), behavior or conduct problems (AOR 4.06 [95% CI 2.72, 6.06]), and other mental health conditions. Similarly, compared to children with ADHD without ASD, children with ASD + ADHD had higher odds of anxiety (AOR 3.49 [95% CI 2.65, 4.61]), depression (AOR 1.67 [95% CI 1.21, 2.29]), behavior or conduct problems (AOR 2.31 [95% CI 1.68, 3.17]), and other mental health conditions. Children with ASD + ADHD were significantly more likely to take psychotropic medication than children with ASD without ADHD. Among children with ASD + ADHD, males had higher odds of receiving behavioral treatment, whereas older children and adolescents were more likely to take psychotropic medication. A multidisciplinary approach is necessary to support the complex needs of these children.