Study explores autism co-occurring conditions and diagnosis change

The study, “Co-occurring Conditions and Change in Diagnosis in Autism Spectrum Disorders,” was published online January 23 and will appear in the February edition of Pediatrics. The authors, Heather Close, Li-Ching Lee and Christopher N. Kaufmann of Johns Hopkins Bloomberg School of Public Health, and Andrew W. Zimmerman of Massachusetts General Hospital for Children, found that the type and number of co-occurring conditions vary by children’s age. These conditions include anxiety, depression, developmental delay, speech problems and seizures.

“Our study found that children with a current ASD are more likely to have co-occurring conditions compared to children who no longer have an ASD diagnosis,” said Close, the study’s lead author.

The study analyzed data of parent-reported ASD diagnoses from 1,366 children in the National Survey of Children’s Health 2007 dataset by three age groups: young children (3-5 years); children (6-11 years); and adolescents (12-17 years). In the survey, parents of children in each age group were asked whether their child had a current ASD diagnosis, or had received the diagnosis in the past but no longer has the diagnosis.

The percentage of children found to have an ASD diagnosis change were 25 percent, 33 percent, and 35 percent for young children, children and adolescents, respectively. Across all age groups, children with a current ASD diagnosis were more likely to have at least two co-occurring conditions, compared to children who no longer had the diagnosis.

Co-occurring conditions of ASD varied by age. Among the youngest children, those with a current ASD diagnosis were more likely to have a current moderate/severe developmental delay and current moderate/severe learning disability compared to children who no longer had the diagnosis. In children ages 6 to 11, those with current ASD had past speech problems, as well as current moderate/severe anxiety disorders, compared to children who no longer had the diagnosis. Finally, in the adolescent group, those with ASD were more likely to have current moderate/severe speech problems and current seizures compared to children who no longer had the diagnosis.

“Clinicians working with children with ASD need to recognize that certain co-existing conditions of autism differentiate children who continue having the diagnosis from children who no longer have the diagnosis,” said the senior author, Lee, a psychiatric epidemiologist at the Bloomberg School of Public Health. “Beside the core symptoms of autism, the clinicians would need to evaluate the child on these conditions.”  

The message is the same for parents, “They should have their child evaluated for possible co-existing conditions, in addition to core symptoms of ASD to make sure an ASD diagnosis is properly determined. That way, a more appropriate intervention for the child can be planned as early as possible,” Lee added.

Provided by Johns Hopkins Bloomberg School of Public Health