by Dr. Brandon J. Henscheid, MS, PsyD
The connection between ADHD and Autism Spectrum Disorder (autism) has been the subject of greater attention, research, and clinical evaluation over the past decade. The prevalence of both conditions have increased over time as both disorders have become better understood by both the public and clinicians, and access to assessment has been made more available. These conditions often co-occur despite having separate, well-defined diagnostic criteria. Studies have indicated that approximately 30 to 50% of individuals diagnosed with autism exhibit symptoms of ADHD, with some estimates as high as 71%.
Autism and ADHD are classified as Neurodevelopmental Disorders by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), which are disabilities that manifest due to differences in the functioning of the brain. These differences may cause impairment in cognition (thinking), behavior, communication, and/or motor skills. These conditions are also typically diagnosed during childhood. ADHD is fairly well understood, while autism can still be puzzling for many as the behaviors associated with it can vary considerably. Autism is a disorder which describes significant limitations in social skills, communication, self-regulation, repetitive behavior, or a combination of these and other symptoms. The severity of autism can range based on specific behaviors measured and is referred to as a spectrum disorder due to the high variability in symptoms among those diagnosed with the condition.
Distinct differences exist between the disorder and it often begins with the emergence of the disorder in children based on age. Symptoms of autism usually emerge between 18-months and three years and may begin with excessive sensory sensitivity to sounds, clothing, or food textures, behavioral rigidity (e.g., an insistence on routines), difficulties acquiring the ability to engage in cooperative play with other children, avoidance of eye contact, absent or inappropriate facial expression, or stereotyped behaviors such as hand flapping or body rocking. Early symptoms of excessive hyperactivity may present in young toddlers as well for children with ADHD, but it can be more difficult to differentiate age-appropriate activity in this age group. Approximately one-quarter of children with ADHD have predominantly inattentive presentation which usually isn’t identified until they are school-aged or it can be missed completely as the behaviors associated with this subtype are not disruptive.
Although they are distinct psychiatric disabilities, there are occasions when symptoms of the conditions can overlap which can raise the question of accurate diagnosis. Individuals with ADHD and autism may experience challenges with socialization, planning, organization, friendship building, and communication, but determining the source of the impairment may require more in-depth analysis and a specialized assessment. Autism is a lifelong condition that typically requires a comprehensive evaluation by a clinical psychologist or another specialist authorized to assess and make a diagnosis. Treatment options can also vary depending on the symptoms and severity, but accurate diagnosis is the starting point to provide individualized recommendations to enhance the possibility of more favorable prognostic outcomes.
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