Can Autism Accompany ADHD? New Research Says Yes

Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) can appear together, new research reveals.

Proving this, researchers at the Kennedy Krieger Institute found that a significant number of autistic children - nearly one-third - were also suffering from ADHD.

Autism spectrum disorder (ASD) is a developmental disorder that leads to significant social, communication and behavioral changes. A latest report from the Centers for Disease Control and Prevention (CDC) states that one in every 50 school children in the U.S. is affected with autism.

ADHD is a neurobehavioral disorder of childhood. Children experiencing ADHD face problems in paying attention, find it difficult to control impulsive behaviors (acting without thinking about the consequences), and are prone to hyper-activity.

"We are increasingly seeing that these two disorders co-occur and a greater understanding of how they relate to each other could ultimately improve outcomes and quality of life for this subset of children," Dr. Rebecca Landa, senior study author and director of the Center for Autism and Related Disorders at Kennedy Krieger, said in a news release.

The study, reported in Autism: The International Journal and Practice, included 162 children - both autistic (63) and non-autistic. Based on parental interviews and standard tests used to identify ADHD, researchers found that 18 of the 63 autistic children had "clinically significant symptoms" of ADHD. The children who entered the study as infants or toddlers were aged between 4 and 8 years at the time of ADHD diagnosis.

Another important finding of the study was that children with both the disorders are more likely to exhibit more severe symptoms of autism, such as stereotyped and repetitive behaviors, unlike children only affected with autism. Cognitive, social and adaptive functions were found to be more damaged among autistic children with ADHD, making them struggle more at school compared to others.

Concerned with the findings, Dr. Landa urges for the need to spread more awareness about this occurrence, welcoming a recent move by authorities to remove a ban on the dual diagnostic system used to identify the co-occurrence of the disorders.

"The recent change to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to remove the prohibition of a dual diagnosis of autism and ADHD is an important step forward," Dr. Landa said, later adding, "the earlier we can identify this subset of children, the earlier we can design specialized interventions."