This poster was presented at the 30th annual Psych Congress, held Sept. 16-19, 2017, in New Orleans, Louisiana.
About one in eleven cannabis users meet criteria for cannabis use disorder (CUD), a condition marked by continued use despite adverse psychosocial and health outcomes. In this secondary analysis, we examined self-reported ratings on the Marijuana Problem Scale (MPS) (number of items endorsed, total score) among adult participants enrolled in a multi-site trial of N-acetylcysteine (NAC) for CUD. Participants (N=302, ages 18-50) were randomized to a 12-week course of double-blind NAC (1200 mg, twice daily) or placebo. Participants who completed at least one treatment visit and all required MPS self-reports were included in the analysis. The MPS measured negative life problems associated with cannabis use and was administered during baseline, treatment weeks 5 and 9, end-of-treatment, and 1-month follow-up. Specimen collection of urinary cannabinoid and creatinine were performed during baseline, all treatment visits, end-of-treatment, and 1-month follow-up. Over the course of the trial participation, concurrent cannabinoid levels were positively and significantly associated with numbers of MPS items endorsed (p=0.012). Additionally, the gradual decline in endorsed MPS items did not differ significantly between NAC and placebo groups (p=0.054). The positive association between endorsed MPS items and quantitative urine cannabinoid level suggests that higher cannabis intake predicts more cannabis-related problems. Amid the national increase in cannabis consumption and CUD cases, future research should employ the MPS towards a nationally representative sample size of cannabis users and further assess the relationship between dosage intake and cannabis-related problems.