Among children with autism spectrum disorder, study findings revealed that ADHD symptoms were linked to poorer adaptive behavior across all settings and after controlling for key confounders.
“Given that up to 25% of children with ASD present with subclinical ADHD symptoms, demonstrating that ADHD symptoms have a dimensional effect on adaptive behavior would highlight a treatment target even for those children who do not meet traditional diagnostic criteria for an ADHD diagnosis,” Benjamin Yerys, PhD, of the Center for Autism Research at Children’s Hospital of Philadelphia, and colleagues wrote.
Using a case-control study, researchers examined the predictive power of comorbid ADHD on adaptive behavior skills in 347 children with ASD. Caregivers and teachers rated the frequency of 18 ADHD symptoms and the child’s behavior on an average day at home and school.
The investigators used linear regression to determine whether ADHD-IV Rating Scale scores were tied to poorer adaptive behavior scores after adjusting for age, IQ, gender and autism symptom severity. They also performed subsequent analyses to determine this relationship in a subset of participants with subclinical ADHD symptoms (n = 179) and another with teacher-rated diagnostics (n = 153).
Yerys and colleagues found that ADHD symptoms can predict up to about 12% additional variance in adaptive behavior scores among children with autism, according to the results.
Analysis demonstrated that after controlling for confounders, ADHD symptoms predicted lower adaptive behavior scores in the full sample of children with autism (parent ratings: R2 = 0.033-0.119; teacher ratings: R2 = 0.113-0.163) as well as in those with subclinical ADHD symptoms (caregiver ratings: R2 = 0.023-0.03; teacher-ratings: R2 = 0.097-0.159). Furthermore, the researchers found that the link between ADHD symptoms and adaptive behaviors was present even if the child with ASD did not have an ADHD diagnosis, according to a press release.
Correlation analyses revealed that adaptive behaviors and ADHD symptoms decreased with age in all children with autism. In addition, the effect of ADHD symptoms on adaptive behaviors was not moderated by age, the data showed.
"To move this research forward, we must define brain and behavioral profiles related to cognitive control and other key brain processes that underlie ADHD symptoms in the context of autism," Yerys said in the release. "By doing so, we can establish different treatments or treatment packages for the different profiles of ADHD in the autism population. Our hope as a field is that a more personalized approach to treatment will increase the potential of better long-term outcomes and quality of life, with treatment packages potentially including medications and behavior therapies." – by Savannah Demko
Disclosure: Yerys reports funding from Aevi Genomic Medicine, Akili Interactive Labs Inc, National Institute of Child and Human Development, NIMH and the McMorris Family Foundation. He also reports consulting for Aevi Genomic Medicine. Please see the study for all other authors’ relevant financial disclosures.