No Evidence for Efficacy of Brief Interventions for Cannabis Use in Healthcare Settings

Researchers summarized the available evidence for the efficacy of brief interventions for cannabis use in healthcare settings.

• Of the 9 studies identified, 8 were conducted in the US (of these, 1 also recruited participants from Australia, Brazil, and India); 1 was conducted in Chile.
• Most studies were conducted in primary care or emergency departments (n=8).
• The majority of interventions were based on motivational interviewing (n=8).
• In a meta-analysis, there were no effects of brief interventions on cannabis ASSIST scores, or on the number of days of cannabis use in the past 30 days, both in the short term (≤ 3 months) and long term (>3 months).
• For outcomes not included in the meta-analysis (cannabis use frequency, getting high on cannabis, abstinence, consequences, driving under the influence), evidence was mixed and limited.

Comments: Evidence for the efficacy of brief interventions for at-risk drinking cannot be extrapolated to other substances; when non-treatment-seeking people with cannabis use are identified by screening in healthcare settings, there is currently no evidence for efficacy of brief interventions. Nevertheless, these results do not imply that cannabis use should not be addressed in primary care settings since knowing about a patient’s cannabis use may influence clinical care.

Nicolas Bertholet, MD, MSc

Reference: Imtiaz S, Roerecke M, Kurdyak P, et al. Brief interventions for cannabis use in healthcare settings: systematic review and meta-analyses of randomized trials. J Addict Med. 2019 [Epub ahead of print]. doi: 10.1097/ADM.0000000000000527.