The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) describes both Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) as neurodevelopmental disorders. Until 2013, clinicians were not allowed to diagnose an individual with both ADHD and autism concurrently. However, research in 2013 showed links between ASD and ADHD, resulting in an increase in the number of people diagnosed with both conditions. While estimates vary, the Centers for Disease Control and Prevention (CDC) states that 14% of children diagnosed with ADHD are also diagnosed with ASD, and more than half of autistic children are also symptomatic with ADHD.
Overlapping Characteristics
ADHD and ASD are typically identified during the childhood years, although symptoms of both disorders may last throughout the affected individuals’ lives. Diagnosis of ADHD and ASD is often complicated by the fact that traits may overlap even if they are not part of the official diagnostic criteria. For example, children with ADHD are characteristically distractible and impulsive. These traits also appear in most individuals with autism, although they are not included in the official symptoms of ASD. Conversely, speech delays and spoken idiosyncrasies are a characteristic of autism spectrum disorder, but are also commonly found in those with ADHD, although neither trait is officially listed as part of an official ADHD diagnosis. Here are some symptoms that are commonly exhibited by individuals with ADHD and ASD:
- Challenges with making friends and interacting in social situations (in ADHD, this may come from impulsivity, control issues, or the inability to meet group norms; in ASD, this may stem from speech problems or the inability to understand physical cues)
- Difficulty controlling frustration and anger
- Executive functioning issues, causing problems with organization of projects, tasks, and time
- Impulsivity issues, such as blurting out or moving at inappropriate times
- Lack of focus (in ADHD, distraction comes from external stimuli; in ASD, distraction is internal)
- Learning disabilities and differences
- Sensory issues, with over- and under-sensitivity to stimuli like touch, sounds, and sights
Causes
The causes of both neurodevelopmental disorders are still under investigation by researchers around the world. Studies indicate that both conditions have genetic components, but suspected environmental issues have also been pinpointed. Brain chemistry and structures are still being explored for ASD, ADHD, and additional developmental issues. The common risk factors for both autism and ADHD include the following:
- Exposure to alcohol, drugs, or tobacco during pregnancy
- Environmental risk factors, including lead paint, exposed during the pregnancy or the affected individual’s early years
- Low birth weight
- Premature delivery
Diagnosis
While there is no single medical test to provide an official, accurate diagnosis of ADHD or ASD, the two disorders are diagnosed using similar procedures.
- Both disorders are usually diagnosed in children, as young as 18 months.
- Diagnosis for both disorders begin with a screening by the pediatrician, including questions about behavior and development. A full evaluation is recommended if red flags appear in the screening.
- Specialists utilize a variety of assessments to measure speech and language development, IQ, behavioral history, medical history, and growth patterns.
Diagnosis of ADHD and ASD may be complicated by the overlapping symptoms, but an accurate diagnosis is important for proper treatment. Visit WPS for useful information about screening procedures for both neurodevelopmental disorders.
