Types of Adult Attention-Deficit Hyperactivity Disorder (ADHD): A Replication Analysis

Background: Research supports the importance of emotional symptoms in ADHD adults, symptoms not reflected in the DSM-5 or IDC-10 criteria. The Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) assesses these symptoms, plus inattention, hyperactivity and impulsivity. This range of ADHD symptoms allowed us to divide adult ADHD into two subtypes in a 2015 publication: ADHD Inattentive presentation and ADHD Emotional dysregulation presentation. In the present study, we refine this observation using a larger, more diverse sample. Methods: WRAADDS data from additional clinical trials (1,493 subjects) were subjected to confirmatory factor analyses and ADHD presentations were compared, including treatment response. Outcome: Our original factor structure fit poorly with these new data. However, an alternative 2 factor solution fit both the original and the new subjects. ADHD Inattentive presentation was defined by the Inattention factor. ADHD Emotional dysregulation presentation was defined by additional elevation of the Emotional Dysregulation factor. The proportion of ADHD Emotional Dysregulation Presentation ranged from 30 to 70% across the 8 studies and it was associated with both a greater severity as measured by the Clinical Global Impression-Severity scale and more manifestations of childhood ADHD as measured by the Wender Utah Rating Scale. Interpretation: Factor analytic results supported the validity of two adult ADHD presentations based on levels of emotional dysregulation. This system offers a more clinically relevant approach to the diagnosis of ADHD in adults than does the DSM system. Funding Statement: Data came from clinical trials supported by Eli Lilly, Glaxo-Welcome, NIMH, Shire, McNeil PPPC, and Medice. This reanalysis was funded by the authors. Declaration of Interests: None of the authors have a financial interest that will be affected by the results of this article. Ethical Approval Statement: The authors selected published clinical trials of psychotropic medications used to treat ADHD in adults conducted using similar protocols. All met Declaration of Helsinki ethical criteria and were approved by relevant research review boards.