Substance Use Disorder in Adults with ADHD in South Dakota

Attention-deficit hyperactivity disorder (ADHD) increases the risk for multiple comorbid psychiatric disorders, such as substance use disorder. Comorbid ADHD and substance use disorder has been shown to increase the risk of adverse occupational, social, psychological, and physical outcomes. Because of the severe risks of substance use, it is useful to determine the relative comorbidity of ADHD among different types of substance use disorders. This study examined the prevalence of ADHD in residential addiction treatment as well as the relative prevalence of ADHD among mono-substance use, comorbid substance use (2 comorbid substance use disorders), and polysubstance use (3+ substance use disorders).

Participants were adults admitted to residential treatment of substance use disorder. Participants were asked to complete a Wender Utah ADHD rating scale to assess the presence of ADHD. A cutoff score of 46 was used to determine presence of ADHD in this rating assessment. Participants were also provided with an ADHD history questionnaire designed for this study to gather information on childhood ADHD diagnoses, substance use history, and early-life effects o f attention disorders.

Using the Wender Utah assessment scores, 55 participants with substance use disorder demonstrated an ADHD prevalence of 45% (n=30). Of the study population, 20% (n=11) of participants being diagnosed in childhood and another 25% (n=14) having a positive Wender Utah questionnaire score for ADHD as adult patients without a childhood diagnosis. All participants who had a childhood diagnosis of ADHD had received treatment for this disorder. Polysubstance use disorder (n=21) had an ADHD prevalence of 62%. Alcohol use disorder (n=21) had an ADHD prevalence of 24%. Methamphetamine use disorder (n=4) had an ADHD prevalence of 75%. Participants with ADHD (either during childhood or adulthood) had a nearly significant increase in the prevalence of polysubstance use disorder as compared to participants without ADHD (p = 0.0542).

ADHD and substance use disorder have notable comorbidity. This study, among similar studies, demonstrates a high prevalence of ADHD in populations with substance use disorder. The presence of ADHD in patients with substance use disorder may influence which substances those patients choose to use. The difference in patients treated for childhood ADHD and those having a diagnosis of ADHD demonstrates a deficit in effective childhood ADHD screening. As such, effective screening and prevention of substance use disorder in patients with ADHD may be a useful tool in reducing the risk of developing substance use disorder. Additionally, adequate treatment of ADHD could be considered useful in treating a contributing element of substance use disorder.