A 2013 study, Autistic Traits in Children With and Without ADHD, suggests that kids with ADHD are 20 times more likely to exhibit some traits of autism spectrum disorder compared with non-ADHD kids. Just like ADHD, there isn’t a lab test to diagnose autism. Autism is characterized by difficulty in communicating and forming relationships, and in using language and abstract concepts. Some early symptoms are extreme sensory sensitivities, lack of social skills or a preference to be alone, little understanding of abstract language, and obsessive interests. Early detection and treatment of autism are important, but because symptoms of both conditions overlap, diagnosing and separating the disorders can be difficult.
The latest Diagnostic and Statistical Manual of Mental Disorders (DSM-V) opens the possibility that an individual can be diagnosed with both ADHD and autism spectrum disorder (ASD), which was not the case before. Studies show that 30 to 50 percent of individuals with autism show symptoms of ADHD, and that up to 60 percent of individuals with ADHD have symptoms of autism. That means there’s a substantial possibility that an individual with ADHD could also have autism.