Risky business: a longitudinal study examining cigarette smoking initiation among susceptible and non-susceptible e-cigarette users in Canada

Introduction:
This text is a summary of a longitudinal study examining the relationship between e-cigarette use among never-smoking adolescents and smoking initiation in a Canadian context. The study also explores the differential association between e-cigarette use and subsequent smoking initiation among distinct risk groups, specifically non-susceptible never-smokers (ie, low risk) versus susceptible never-smokers (ie, high risk).

Key Points:

* The study used data from the COMPASS study, a prospective cohort study (2012–2021) designed to gather longitudinal and hierarchical data from a sample of secondary school students in Canada.
* The study examined transitions in smoking behavior among adolescents at different risk levels (ie, susceptible and non-susceptible never-smokers) using data from Year 2 (2013–2014) and Year 4 (2015–2016) of the study.
* The study measured e-cigarette use at baseline and smoking initiation at baseline and follow-up.
* The study found that current e-cigarette users were more likely to try a cigarette 2 years later, and this association was stronger among the sample of non-susceptible never-smokers (AOR=5.28, 95% CI 2.81 to 9.94; p<0.0001) compared with susceptible never-smokers (AOR=2.78, 95% CI 1.84 to 4.20; p<0.0001).
* The study also found that a higher proportion of current e-cigarette users reported being male, having friends who smoked cigarettes, and reporting being susceptible to smoking cigarettes in the future.
* The study controlled for gender, grade, self-reported ethnicity, self-reported spending money, and the number of friends who smoke cigarettes at baseline.
* The study had a large sample size of 9501 students and used passive consent procedures to increase participation rates.

Main Message:
The main message of this study is that e-cigarette use among never-smoking adolescents may contribute to the development of a new population of cigarette smokers, particularly among low-risk youth. The study also highlights the importance of considering the regulatory environment for e-cigarettes, as Canada's distinct regulatory policies may have an impact on the relationship between adolescent e-cigarette use and subsequent cigarette smoking initiation. Overall, the study suggests that careful consideration is needed in developing an appropriate regulatory framework that prevents e-cigarette use among youth.

Aleyan, Sarah, Adam Cole, Wei Qian, and Scott T Leatherdale. “Risky Business: A Longitudinal Study Examining Cigarette Smoking Initiation among Susceptible and Non-Susceptible e-Cigarette Users in Canada.” BMJ Open 8, no. 5 (May 2018): e021080. https://doi.org/10.1136/bmjopen-2017-021080.