Substance Use Disorder in Adults with ADHD in South Dakota.

Objective: Attention-deficit hyperactivity disorder (ADHD) increases the risk for comorbid psychiatric and substance use disorders. This study examined the prevalence of ADHD in residential addiction treatment and the prevalence of monosubstance, comorbid substance, and polysubstance use disorders (PUD) as a function of ADHD status.

Method: All adults admitted to residential substance use disorder treatment center in South Dakota during November 2021 to June 2022 were included (N= 55). The participants underwent a clinical interview and objective assessment to determine ADHD status. The participants were also administered ADHD questionnaire developed by investigators to assess ADHD history and treatment. SAS statistical software using an α level of 0.05 was used for all analyses.

Results: Almost half, 25 of the total 55 participants, had ADHD (45%). A quarter (n=14) of participants were diagnosed with ADHD during childhood. A fifth (n=11) of participants were diagnosed with ADHD during this study. Thirty participants (54%) were not found to have ADHD. A majority of ADHD patients (n=21; 84%) were diagnosed with PUD. Participants with ADHD had a higher prevalence of PUD (p=0.054) compared to participants without ADHD. Approximately a quarter of patients with alcohol use disorder and three-quarters of patients with methamphetamine use disorder had ADHD.

Conclusions: ADHD and substance use disorders have notable comorbidity. This study demonstrates a high prevalence of ADHD in populations with substance use disorder. The presence of ADHD may be a risk factor for PUD.