Diagnosing Adult Attention Deficit/Hyperactivity Disorder in Patients with Cocaine Dependence: Discriminant Validity of Barkley Executive Dysfunction Symptoms

Abstract

Objective: To estimate the prevalence of adult attention deficit/hyperactivity disorder (ADHD) in a sample of cocaine-dependent patients, and to examine the discriminant validity of the Barkley’s executive dysfunction scale in differentiating cocaine-dependent patients with and without ADHD. Methods: A cross-sectional design was used. A total of 166 cocaine-dependent subjects were assessed. The assessment instruments included: Conners’ Adult ADHD Diagnostic Interview for DSM-IV (CAADID), Psychiatric Research Interview for Substance and Mental Disorders (PRISM-IV) and 9 items from Current Behavior Scale Self-Report by Russell A. Barkley. Results: 14.5% (CI95%: 9.2–19.8%) prevalence of ADHD was observed in our sample. The Barkley’s executive dysfunction items showed statistically significant differences between cocaine-dependent patients with ADHD and those patients without ADHD diagnosis. Conclusions: The study data support Barkley’s model – which posits the relevance of executive dysfunction among ADHD patients within a sample of cocaine dependents, and provides evidence of the discriminant validity of the Current Behavior Scale Self-Report for identifying ADHD symptoms in cocaine users.