Association Between Electronic Cigarette Use and Marijuana Use Among Adolescents and Young Adults: A Systematic Review and Meta-analysis.

Introduction:
This text provides a summary and analysis of a systematic review and meta-analysis examining the association between electronic cigarette (e-cigarette) use and marijuana use among adolescents and young adults. The study aimed to characterize and quantify the strength of this association.

Key Points:

* The meta-analysis included 21 studies, with a total of 128,227 participants.
* The pooled odds ratio (AOR) for the association between e-cigarette use and marijuana use was 3.47 (95% CI, 2.63-4.59), indicating a significant positive relationship.
* The association was consistent in both longitudinal and cross-sectional studies.
* The odds of marijuana use were higher in adolescents (aged 12-17) with e-cigarette use compared to young adults (aged 18-24).
* The association was stronger in studies with participants who used both e-cigarettes and cigarettes or other tobacco products compared to those who used e-cigarettes only.
* The association between e-cigarette use and marijuana use may be stronger in North American studies compared to European studies.
* More recent studies had a higher pooled AOR than older studies, suggesting a potential increase in the strength of the association over time.

Main Message:
This meta-analysis highlights a significant association between e-cigarette use and marijuana use among adolescents and young adults. The findings suggest that addressing e-cigarette use early on may be an effective way to delay the onset of marijuana use and reduce the burden of substance use on a population level. The results also emphasize the importance of considering e-cigarettes in the broader context of nicotine and tobacco use prevention efforts. Additionally, the study highlights the need for further research to better understand the temporal association between nicotine exposure through e-cigarette use and subsequent changes in marijuana use.

Chadi N, Schroeder R, Jensen JW, Levy S. Association Between Electronic Cigarette Use and Marijuana Use Among Adolescents and Young Adults: A Systematic Review and Meta-analysis. JAMA pediatrics. 2019;173(10):1. doi:10.1001/jamapediatrics.2019.2574