Since the introduction of e-cigarettes to the U.S. market, use has increased rapidly among youth. Some have argued that, while not optimal, this increase represents kids who would otherwise have smoked cigarettes. In particular, Levy et al (Levy et al., 2017, Levy et al. 2018) concluded that the decline in U.S. youth cigarette smoking accelerated following the introduction of e-cigarettes, but Dutra and Glantz, 2017 using the 2004–2014 National Youth Tobacco Survey found that the rate of decline in cigarette smoking among youth did not change with the introduction of e-cigarettes. Consistent with work by others, Dutra and Glantz also found that many of the youth initiating nicotine use with e-cigarettes had risk profiles that made it unlikely that that they would start nicotine use with conventional cigarettes, thereby expanding the amount of nicotine addiction.
Given the changes in youth e-cigarette use since 2011, including the substantial increase in use during 2017–2018, MeLisa Creamer and colleagues (including Lauren Dutra and me) updated the Dutra and Glantz (2017) analysis by adding 4 years of data (through 2018) to assesses: (1) whether the historical declining trend in cigarette smoking and combined use of cigarettes and/or e-cigarettes changed after the uptake of e-cigarettes by youth; and (2) whether the risk profile of youth e-cigarette users would match established demographic and psychosocial predictors of youth cigarette smoking.
We found that the introduction of e-cigarettes was followed by a slowing of the decline in current cigarette smoking and an acceleration in the ever cigarette smoking trend. Most youth who use e-cigarettes but not cigarettes had risk profiles that made it unlikely that they would initiate nicotine use with cigarettes and probably would have remained nicotine free had e-cigarettes not been available. In sum, the advent of e-cigarettes has reversed progress in reducing nicotine addiction among youth.
Since we completed this work and while it was working its was through peer review and publication, CDC published 2019 data that showed that e-cigarette and total tobacco use continued to increase in 2019, The CDC then published “E-cigarette Use Among Middle and High School Students — United States, 2020,” which showed that “in 2020, approximately one in five high school students and one in 20 middle school students currently used e-cigarettes. By comparison, in 2019, 27.5% of high school students (4.11 million) and 10.5% of middle school students (1.24 million) reported current e-cigarette use (2). Although these data reflect a decline in current e-cigarette use since 2019, 3.6 million U.S. youths still currently used e-cigarettes in 2020, and among current users, more than eight in 10 reported using flavored e-cigarettes.” They did not report cigarette or other tobacco use, so total tobacco use is not available, but, comparing the e-cigarette prevalence they reported to what we reported for 2018, overall nicotine use almost certainly is substantially higher among youth than it would have been without the advent of e-cigarettes.
Here is the abstract for the new Creamer et al paper:
Objective: To determine if the declining trend in U.S. youth cigarette smoking changed after e-cigarettes were introduced, and if youth e-cigarette users would have been likely to smoke cigarettes based on psychosocial and demographic predictors of smoking.
Methods: An interrupted time series analysis was used for cross-sectional data from the 2004 to 2018 National Youth Tobacco Surveys (NYTS) to assess changes in cigarette and e-cigarette use over time. A multivariable logistic regression model used 2004–2009 NYTS data on psychosocial risk factors to predict individual-level cigarette smoking risk from 2011 to 2018. Model-predicted and actual cigarette smoking behavior were compared.
Results: The decline in current cigarette smoking slowed in 2014 (−0.75 [95% CI: −0.81, −0.68] to −0.26 [95% CI: −0.40, −0.12] percentage points per year). The decline in ever cigarette smoking accelerated after 2012 (−1.45 [95% CI: −1.59, −1.31] to −1.71 [95% CI: −1.75, −1.66]). Ever and current combined cigarette and/or e-cigarette use declined during 2011–2013 and increased during 2013–2014 with no significant change during 2014–2018 for either variable. The psychosocial model estimated that 69.0% of current cigarette smokers and 9.3% of current e-cigarette users (who did not smoke cigarettes) would smoke cigarettes in 2018.
Conclusions: The introduction of e-cigarettes was followed by a slowing decline in current cigarette smoking, a stall in combined cigarette and e-cigarette use, and an accelerated decline in ever cigarette smoking. Traditional psychosocial risk factors for cigarette smoking suggest that e-cigarette users do not fit the traditional risk profile of cigarette smokers.
The full citation is:
MeLisa R. Creamer, Lauren M. Dutra, Saida R. Sharapova, Andrea S. Gentzke, Kevin L. Delucchi, Ruben A. Smith, Stanton A. Glantz. Effects of e-cigarette use on cigarette smoking among U.S. youth, 2004–2018. Preventive Medicine 2020, 106316, ISSN 0091-7435, https://doi.org/10.1016/j.ypmed.2020.106316. It is available here.