The structure of adult ADHD.

Although DSM-5 stipulates that symptoms of attention-deficit hyperactivity disorder (ADHD) are the same for adults as children, clinical observations suggest that adults have more diverse deficits than children in higher-level executive functioning and emotional control. Previous psychometric analyses to evaluate these observations have been limited in ways addressed in the current study, which analyzes the structure of an expanded set of adult ADHD symptoms in three pooled US samples: a national household sample, a sample of health plan members, and a sample of adults referred for evaluation at an adult ADHD clinic. Exploratory factor analysis found four factors representing executive dysfunction/inattention (including, but not limited to, all the DSM-5 inattentive symptoms, with non-DSM symptoms having factor loadings comparable to those of DSM symptoms), hyperactivity, impulsivity, and emotional dyscontrol. Empirically-derived multivariate symptom profiles were broadly consistent with the DSM-5 inattentive-only, hyperactive/impulsive-only, and combined presentations, but with inattention including executive dysfunction/inattention and hyperactivity-only limited to hyperactivity without high symptoms of impulsivity. These results show that executive dysfunction is as central as DSM-5 symptoms to adult ADHD, while emotional dyscontrol is more distinct but nonetheless part of the combined presentation of adult ADHD.