Prevalence of comorbid substance use disorder during long-term central stimulant treatment in adult ADHD

Central stimulant (CS) therapy is a cornerstone in treatment of adult attention-deficit/hyperactivity disorder (ADHD). Substance use disorder (SUD) is a common comorbid disorder of ADHD and might complicate the treatment. Our main objectives were to investigate the prevalence of SUD during CS treatment, and identify variables associated with SUD during the treatment. The collection of data was based on a naturalistic, retrospective approach using the medical records of a cohort of all adult ADHD patients (N = 117) starting treatment with CS in a specific catchment area in the period 1997 to May 2005. A logistic regression model was applied to identify possible predictors of SUD during CS treatment. The study showed no onset of SUD during the CS treatment in the group of patients without comorbid SUD at baseline (mean CS treatment length 41.1 months). In the group of patients with comorbid SUD at baseline, 58.5 % had one or more relapses of SUD during treatment (mean CS treatment length 27.9 months). Younger age and comorbid antisocial personality disorder were associated with relapse. In a logistic regression analysis, cannabis abstinence for more than 12 months was a negative predictor for relapse of SUD. CS treatment does not precipitate onset of SUD in adults without previous SUD.