ADHD Diagnosis and Treatment Among ADHD Children with and without ASD

Background:  Children diagnosed with autism spectrum disorder (ASD) are commonly diagnosed with other co-occurring developmental, psychiatric, neurological and medical conditions (Levy et al., 2010).  The most prevalent psychiatric co-occurring condition is attention-deficit/hyperactivity disorder (ADHD), with approximately one in two children with ASD also having ADHD (Zablotsky et al., 2015).  Parents of children diagnosed with ASD frequently report obstacles in accessing and receiving care for their child’s ASD (Kogan et al., 2008).  However, little is known about how a child’s ASD may affect the ability to receive care for other mental health conditions, more specifically whether a diagnosis of ASD may make receipt of services for ADHD easier or more difficult among children with both conditions. 

Objectives: 1) Compare the age of ADHD diagnosis and the age of first ADHD medication between children currently diagnosed with ADHD and ASD to children currently diagnosed with ADHD without ASD, 2) Explore whether ADHD treatment barriers and parental satisfaction of their child’s ADHD management and treatment vary by whether a child is currently diagnosed with ASD.

Methods:  Data are drawn from the 2014 National Survey of the Diagnosis and Treatment of Attention-Deficit/Hyperactivity Disorder and Tourette Syndrome (NS-DATA), a follow-up to the 2011-2012 National Survey of Children’s Health.  Households with a child between the ages of 4-17 and currently diagnosed with ADHD were eligible for the current study (n=2,464).  Children currently diagnosed with ASD and ADHD (n=352) were compared to those who were diagnosed with ADHD without ASD (n=2,112). 

Prevalence estimates were calculated using Stata 13.1 SE, which accounted for the complex survey design of the NS-DATA.  Differences between children with and without current ASD were compared using multivariate logistic regression, controlling for differences between the groups in demographics, ADHD severity, and the impact of the child’s ADHD on the family.  Interaction terms were used to test whether the effects of covariates differed by whether the child had ASD or not.

Results: Among children with ADHD, those with ASD were diagnosed with ADHD at an earlier age and started treatment with medication for ADHD at an earlier age.  Approximately 11% of children with ADHD had trouble obtaining treatment for their ADHD regardless of whether the child was currently diagnosed with ASD.  Additionally, children in the two groups had parents who were equally satisfied with the ADHD treatment and management their child receives.

The effects of most covariates did not differ by whether the child has a current ASD diagnosis, with two exceptions: girls had a later age of first ADHD medication than boys, unless they had ASD, in which case they had a younger age than boys; and non-Hispanic black children had a higher unmet treatment need than all other children if they had been diagnosed with ASD.  

Conclusions:  The presence of ASD may prompt diagnostic services for a developmental disorder at an earlier age.  However, after receiving an ADHD diagnosis, children with ASD do not appear much different than children without ASD.