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

Sun et al studied more than 8000 cigarette-naive youths from [Population Assessment on Tobacco Use and Health (PATH)] waves 3 to 5. They found that 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. Moreover, 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. In other words, while e-cigarette use was associated with future cigarette smoking, the pattern of cigarette smoking itself was not clinically meaningful.

[..] the most recent data from the 2022 NYTS [National Youth Tobacco Survey] not only highlighted concerning rates of e-cigarette use (14.1%), it also documented the lowest rate of cigarette smoking (2.0%) ever recorded for high school–aged youths. This is notable, considering that in 2009, around the time when e-cigarettes were introduced in the US, the cigarette smoking prevalence was 23.2%. At the population level, e-cigarettes do not appear to be a gateway to cigarette smoking. While cross-sectional surveys, like the NYTS, are limited in exploring trajectories, studies like PATH are well suited to do so. The analysis by Sun and colleagues clearly points to very few youths reporting continued cigarette smoking regardless of baseline e-cigarette use. Collectively, 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. Moreover, future research and policy efforts should give more attention to the common liability theory [the association between e-cigarette use and cigarette smoking can be attributed to a common risk construct of using tobacco products] and consider that in the context of a complex tobacco marketplace, increased diversity in the types of products, brands, and flavors fundamentally provides more opportunities for youths to experiment with tobacco and nicotine products.”

Full article, CD Delnevo, JAMA Network Open, 2023.3.27