ADHD and Marijuana-Use Expectancies in Young Adulthood

Abstract

Objective: This study examined mean level differences in marijuana expectancies and the differential associations between expectancies and marijuana use for individuals with and without a history of Attention-Deficit/Hyperactivity Disorder (ADHD). Background: Substance-use expectancies are a widely studied risk factor for alcohol and other drug use. The relations between marijuana-use expectancies and self-reported marijuana use have not been examined in young adults with ADHD, a population shown to be at risk for marijuana use. Method: Participants were 306 (190 ADHD and 116 non-ADHD) young adults (M age = 20.06, SD = 2.03) from the Pittsburgh ADHD Longitudinal Study (PALS) who provided data about marijuana use and marijuana-use expectancies. Results: Individuals in the ADHD group reported lower levels of social enhancement, tension reduction, and cognitive and behavioral-impairment expectancies compared to individuals in the non-ADHD group. Positive and negative marijuana-use expectancies were associated with marijuana use frequency in the whole sample and statistically significant ADHD group by expectancy interactions were found. Sexual-enhancement expectancies were more strongly associated with marijuana use frequency among individuals with ADHD histories while cognitive behavioral-impairment expectancies were more strongly associated with marijuana use frequency among individuals without ADHD. Conclusions: Marijuana-use expectancies may be acquired, and operate differently, for individuals with and without ADHD histories. Although future research is needed to test this speculation, these differences may be associated with ADHD-related difficulties in higher order cognitive processes that affect the encoding and utilization of expectations regarding marijuana's effects.