Background: The association between emotional dysregulation (ED) and attention-deficit/hyperactivity disorder (ADHD) has been widely documented. However, a consensus has yet to be reached on how to conceptualize this domain within ADHD. Particularly, ADHD + ED may represent a distinct condition, a more severe ADHD, or a comorbidity. We explored these three main hypotheses, investigating clinical differences between patients with ADHD, ADHD + ED, and ED. Methods: In total, 101 participants (ages 18–50) were recruited and divided into four groups: ADHD (N = 23), ED (N = 28), ADHD + ED (N = 27), and HC (N = 23). ADHD and ED were assessed using the Diagnostic Interview for ADHD in adults (DIVA-5) and the Wender–Reimherr Adult Attention Deficit Disorder Scale (WRAADDS). Sociodemographic and clinical variables were compared among the groups. Results: Participants with ADHD and ADHD + ED exhibited comparably high ADHD severity and executive dysfunction ratings. While participants with ADHD + ED shared elevated negative emotionality and higher rates of mood disorders and anxiety disorders with participants with ED compared with those with ADHD, they showed specifically increased developmental and disruptive comorbidities, as well as earlier onset and greater cyclicity of comorbid mood disorders. Psychosocial functional impairments were similarly elevated on average in ADHD + ED and ADHD, but ADHD + ED showed more pronounced and widespread deficits across multiple domains. Conclusions: ADHD + ED is unlikely to represent a more severe form of ADHD but may be more appropriately conceptualized as either a distinct entity or a “comorbid” phenotype. Comparisons with ED without ADHD highlighted clinical features specific to ADHD + ED, including a higher neurodevelopmental load, impulse-control disorders, and a poorer course of mood disorders.
Brancati et al. (2026) studied this question.