Impulsive Personality Traits Mediate the Relationship Between Attention-Deficit/Hyperactivity Disorder Symptoms and Psychiatric Comorbidity among Patients with Severe Alcohol Use Disorder.

Objective: Attention-deficit/hyperactivity disorder (ADHD) is an established risk factor for developing alcohol use disorder (AUD), and AUD-ADHD comorbidity is associated with additional psychiatric diagnoses. Several lines of evidence support the role of impulsivity as a pathway of these relationships; however, impulsivity is not a unitary construct. Thus, we sought to explore whether separate aspects of impulsivity may explain the relationship between ADHD symptoms and psychiatric comorbidity among inpatients (N = 136) with AUD. Methods: We assessed ADHD symptoms (childhood ADHD [Wender Utah Rating Scale], adult ADHD [Adult ADHD self-report scale]), health-related quality of life (HRQL; EQ-5D-5L), psychiatric comorbidity (Mini International Neuropsychiatric Interview), and impulsive personality traits (Urgency, Premeditation, Perseverance, Sensation seeking [UPPS] scale). Results: 19% of patients screened positive in the retrospective assessment of childhood ADHD, and 17% for adult ADHD. Participants reported moderate levels of problem severity in the HRQL dimensions, and 65% had ≥1 current psychiatric disorders other than AUD and ADHD. Multiple mediation indicated that there was a significant direct effect of childhood ADHD symptoms on psychiatric comorbidity (β = 0.224, 95% CI [0.080, 1.114]), and indirect effects of both reacting impetuously when experiencing negative emotions (negative urgency; β = 0.999, 95% CI [0.043, 0.461]) and the tendency to not finish tasks (lack of perseverance; β = 0.075, 95% CI [0.002, 0.297]). Conclusions: The subcomponents of impulsivity to react rashly when experiencing negative emotions and the tendency to not persist in activities seem to contribute to the relationship between ADHD symptoms (particularly those in childhood) and psychiatric comorbidity among patients with severe AUD.