Age at Diagnosis and Clinical and Genetic Profiles Among Adults With Attention-Deficit/Hyperactivity Disorder

Abstract

Key Points Question Do demographic, clinical, and genetic profiles of adults diagnosed with attention-deficit/hyperactivity disorder (ADHD) in adulthood differ from adults diagnosed with ADHD in childhood or adolescence, and how do profiles of both groups compare with matched controls without ADHD? Findings In this cross-sectional study of 13 527 adults with ADHD, adult-diagnosed individuals had significantly fewer psychiatric and somatic comorbidities, less impairment in overall health and daily activities, and lower ADHD polygenic risk scores than youth-diagnosed individuals. Yet both ADHD groups had significantly higher psychiatric and somatic comorbidities, overall functional impairments, and ADHD polygenic risk scores than matched controls. Meaning These findings suggest that adult-diagnosed ADHD may represent a comparatively milder clinical and genetic profile than youth-diagnosed ADHD, yet both groups showed substantial clinical burden.