Marijuana Use Is Associated with Decreased Abstinence from Heavy Alcohol and Other Drug Use in Individuals with Substance Use Disorders
Although marijuana use is common among people with substance use disorders, it is not known whether and how marijuana use should be managed during alcohol and other drug treatment. In this study, researchers conducted a secondary analysis of prospective data from 535 people with DSM-IV alcohol and/or other drug dependence (mean age 38 years, 73% male, 46% white) in a randomized trial of chronic disease management. Adjusted regression models were used to estimate the association of marijuana use (30-day use assessed at baseline, 3 months, and 6 months) with abstinence from heavy alcohol* and drug use** at the subsequent assessment (3, 6, or 12 months).
- At study entry, 17% of participants had alcohol dependence, 26% had drug dependence, and 57% had both.
- 35%, 34%, and 43% reported abstinence from heavy alcohol use and other drug use at 3, 6, and 12 months.
- In adjusted analyses, marijuana use was associated with a 27% reduced odds of abstinence from heavy alcohol use and other drug use.
- In post hoc analyses, greater frequency of marijuana use was associated with decreased abstinence from heavy alcohol use and other drug use.
* Heavy alcohol use defined as ≥4 standard drinks for women and ≥5 standard drinks for men on an occasion at least once in prior 30 days.
** Drug use defined as any use of cocaine, amphetamines, heroin, and non-medical use of other opioids.
Comments:
The mechanisms for this finding are not known. Marijuana use may compromise decision-making, activate brain pathways also influenced by alcohol and other drugs, and nudge individuals into social settings where alcohol and other drugs are available. Although the study does not prove that marijuana cessation counseling will lead to better alcohol and other drug treatment outcomes, I agree with the authors that marijuana use should be identified and addressed in individuals with alcohol and other drug dependence.
Kevin L. Kraemer, MD, MSc
Reference:
Mojarrad M, Samet JH, Cheng DM, et al. Marijuana use and achievement of abstinence from alcohol and other drugs among people with substance dependence: a prospective cohort study. Drug Alcohol Depend. 2014;142:91–97.