Diagnostic consideration for autism spectrum disorder is required when making a diagnosis of attention-deficit/hyperactivity disorder, due to the prevalence of detrimentally late diagnosis of ASD in children with concurrent disorders, according to recent data in Pediatrics.
“Our study supports the hypothesis that receiving a diagnosis of [attention-deficit/hyperactivity disorder (ADHD)] before [autism spectrum disorder (ASD)] may delay the diagnosis of ASD, and that this delay persists across age and severity of the ASD,” Amir Miodovnik, MD, MPH, of the division of developmental medicine at Boston Children’s Hospital and Harvard Medical School, and colleagues wrote. “Furthermore, if ADHD is diagnosed first, the ASD diagnosis has a higher probability of occurring late. ASD that goes unrecognized and untreated until the child is older may negatively affect their long-term prognosis.”
The researchers gathered data from the 2011-2012 National Survey of Children’s Health, and they recorded the ages at which parents reported their children initially were diagnosed with ADHD or ASD. Criteria for confirming a survey respondent had a child with ASD was done through a series of questions, including: “Has a doctor or other health care professional ever told you that your child had autism?” Other survey questions were analyzed to determine whether an ADHD diagnosis was made before, concurrently, or after ASD diagnosis.
Ultimately, 1,496 children, aged 2 to 17 years, with confirmed ASD were included in the final study population, of which 705 also had an ADHD diagnosis. Almost 45% of participants with coinciding ADHD and ASD reported that an ADHD diagnosis was made first. The researchers noted that the group of children who had ADHD diagnosed before ASD contained fewer children with speech problems, compared with children diagnosed first with ASD or simultaneously with ADHD (P = .009). Children in this group also were aged about 4 years older than those diagnosed with ASD before or simultaneously with ADHD (P < .001). Later ASD diagnosis due to earlier ADHD diagnosis resulted in 81% of children in this group not receiving a diagnosis of ASD until after they were aged 6 years (P <.001).
There were 745 children in the study group diagnosed only with ASD, while 392 children were diagnosed with ADHD at the same time or after an ASD diagnosis.
The investigators said that a diagnosis of ADHD before ASD caused at least a 3.2-year delay in a diagnosis of ASD. This delay has the potential to negatively impact the long-term symptoms and quality of life associated with ASD, they said.
Children that presented with speech problems resulted in an ASD diagnosis occurring 1.2 years earlier, the researchers said. Children with mild to moderate ASD also were diagnosed later than children with severe ASD.
“Diagnostic criteria and screening measures for ASD may need to reflect the overlapping symptomatology between ASD and ADHD,” Miodovnik and colleagues wrote. “For now, clinicians should consider ASD when evaluating young children presenting with ADHD symptoms.” – by David Costill
Disclosures: Miodovnik reports no relevant financial disclosures. Another author reports receiving grants from SynapDx.