A new systematic review and meta-analysis has found that people who use cannabis are disproportionately more likely to initiate opioid use and engage in problematic patterns of use than people who do not use cannabis.
One surprising discovery in this meta-analysis, led by researchers at the University of Sydney’s Matilda Centre for Research in Mental Health and Substance Use and published by the journal Addiction, was that there aren’t many good studies on the gateway drug theory.
All six studies had a moderate risk of bias and overlooked important confounding variables such as cannabis use frequency and affiliation with cannabis or opioid-using peers.
Full citation for article: Wilson J, Mills K, Freeman TP, Sunderland M, Visontay R, and Marel C.
Addiction is a monthly international scientific journal publishing peer-reviewed research reports on alcohol, substances, tobacco, and gambling as well as editorials and other debate pieces.