e-Cigarette and Cigarette Use among Youth: Gateway or Common Liability?

Introduction:
This text provides an analysis of the relationship between e-cigarette and cigarette use among youth, examining the gateway hypothesis and the common liability theory. The author, an expert in regulatory matters, summarizes a study by Sun et al. (2023) that investigates the association between e-cigarette use and subsequent cigarette smoking in a longitudinal cohort study. Readers will learn about the study design, key findings, and the main message regarding the implications of these findings for researchers, clinicians, and policy makers.

Key Points:

* The study by Sun et al. (2023) used data from the Population assessment on Tobacco Use and health (PaTh) longitudinal cohort study, focusing on more than 8000 cigarette-naive youths from waves 3 to 5.
* Youths who had used e-cigarettes at baseline (wave 3) had higher odds of continued cigarette smoking, but the absolute risks of continued smoking at wave 5 were very small and did not significantly differ by baseline e-cigarette use.
* The prevalence of frequent smoking, defined as 20 or more days in the past 30 days, 2 years later (wave 5) was so low (0.2%), the authors could not model this outcome due to its rarity.
* The study considered a variety of continued cigarette use behaviors beyond experimentation, such as established and frequent use.
* Youth tobacco-use behaviors are complex, and experimentation with multiple tobacco products is common.
* E-cigarettes were not likely the first tobacco product with which youths experimented, as other products like cigars, smokeless tobacco, and hookah also showed similar associations with cigarette smoking.
* The 2022 NYTS data highlighted concerning rates of e-cigarette use (14.1%), but also documented the lowest rate of cigarette smoking (2.0%) ever recorded for high school–aged youths.

Main Message:
The main message of this text emphasizes that the study by Sun et al. (2023) does not support the gateway hypothesis of e-cigarette use leading to cigarette smoking among youth. While e-cigarette use was associated with future cigarette smoking, the pattern of cigarette smoking itself was not clinically meaningful. Furthermore, the study highlights the importance of considering the common liability theory and the complex tobacco marketplace, which provides more opportunities for youths to experiment with tobacco and nicotine products. The text concludes that concerns about a gateway effect and a potential increase in youth cigarette use following the introduction of e-cigarettes to the US market are not supported by the data. Future research and policy efforts should focus on understanding the common liability theory and addressing the diversity of tobacco products and nicotine delivery systems available to youths.

Delnevo CD. e-Cigarette and Cigarette Use among Youth: Gateway or Common Liability? JaMa network open. 2023;6(3):1. doi:10.1001/jamanetworkopen.2023.4890