INTRODUCTION

Researchers have shown a connection between e-cigarette use and subsequent cigarette use. This study prospectively examines the connection between e-cigarette use and marijuana use.

METHODS

This study used data from the Monitoring the Future panel study of 12th graders in 2014 who were followed up 1 year later (n=305). Past-30-day marijuana use and perceived riskiness of marijuana use for 12th graders who used neither e-cigarettes nor cigarettes (78.6%), only e-cigarettes (10.3%), and cigarettes (with or without e-cigarettes; 11.1%) were compared. Data was analyzed in 2019.

RESULTS

At baseline, 40.1% of e-cigarette only users, 48.8% of cigarette users, and 13.2% of nonusers reported past-30-day marijuana use at baseline. E-cigarette only users were less likely to perceive any marijuana as risky at follow-up than nonusers (AOR=0.15, 95% CI=0.04, 0.65). Similarly, e-cigarette only users were more likely to report past-30-day marijuana use at follow-up than nonusers (AOR=3.82, 95% CI=1.45, 10.04), as were those who used cigarettes (AOR=7.63, 95% CI=2.65, 21.97).

CONCLUSIONS

E-cigarette use, even when not in conjunction with cigarette use, may be a marker of marijuana use risk during the transition from adolescence to young adulthood. The e-cigarette and marijuana use link may strengthen in the future with the increasing trend of adolescents vaping marijuana.