Concurrent Use of E-cigarettes, Combustible Cigarettes, and Marijuana.

Objective: Subgroups of adolescent single and dual e-cigarette and cigarette users have been identified, but usage patterns have changed in recent years, and there has been an increase in marijuana use. Research is needed with current data to identify subgroups of use including marijuana and determine their behavioral correlates.

Methods: We cross classified ever and recent use of e-cigarettes, combustible cigarettes, and marijuana among US high school students in the 2019 Youth Risk Behavior Survey (YRBS), providing 8 different groups. Levels of 14 risk and protective factors were compared across groups in general linear models with demographic covariates using omnibus tests, pairwise comparisons, and planned contrasts. Replicability was tested through identical analyses for 2017 YRBS data.

Results: The nonuser group was 43.9% of the sample. The most frequent user groups were triple users (ever-use proportion: 16.9%), dual (e-cigarette and marijuana) users (15.8%), and exclusive e-cigarette users (13.2%). For risk profiles on levels of psychosocial variables, the triple-user group was typically elevated above all other groups. Exclusive e-cigarette users were above nonusers in risk profile but below dual users (both cigarettes and marijuana). Results were similar for ever use and recent use. The patterning of results in 2019 YRBS data were closely replicated in 2017 YRBS data.

Conclusions: Co-occurrence of e-cigarette, cigarette, and marijuana use is currently substantial among adolescents and is associated with an elevated psychosocial risk profile. This has implications for both epidemiology and prevention studies. Further research is needed to study prevalence and identify pathways to triple use.