E-cigarettes have been the most used tobacco product among young people in the United States since 2014.1 E-cigarette use among US high school students peaked at 27.5% in 2019, and has since declined.1,2 A variety of sociocultural and physiologic factors may contribute to youth e-cigarette use by sex.3 A previous review reported higher rates of e-cigarette use among adolescent males compared with females.4 Although teenage e-cigarette use continues to be a major public health concern, use by sex has received little attention in recent years.
Methods
We analyzed data from the annual National Youth Tobacco Survey (NYTS) and biennial Youth Risk Behavioral Surveillance System (YRBS) for the years 2014 through 2023 and 2015 through 2021, respectively. Descriptions of these surveys can be found in the online Supplemental File (Supplemental Tables 1 and 2). Both surveys used a binary (male or female) measure of respondent’s sex. Gender identity measures were added to NYTS and YRBS in 2021 and 2023, respectively, and thus do not yet provide information on trends over time.
We calculated weighted estimates of current e-cigarette use (Past 30-day) among high school students by sex for each year reported by both surveys since 2014. All analyses were weighted and Taylor Series Linearization was used for variance estimation. Design-corrected Pearson χ2 tests using the second-order Rao and Scott correction were used to compare estimates by sex for each NYTS and YRBS year. All analyses were performed using Stata 18 and its suite of “svy” commands to account for each survey’s complex design features. Stata’s “subpop” command was used for all subpopulation analyses. No observations were deleted. Because of changes in survey administration caused by the coronavirus disease 2019 pandemic, we did not compare estimates over time, instead we compared estimates for males and females within each survey year. See the supplement file for additional analytic details. We adhered to the Preferred Reporting Items for Complex Sample Survey Analysis.5 Archived analytic code can be accessed here: https://osf.io/hg7mt.
Results
Figure 1 depicts e-cigarette use by sex among US high school students using NYTS data. See Supplemental Table 3 for estimates and corresponding 95% confidence intervals (CI). Between 2014 and 2018, male high school students had a higher prevalence of e-cigarette use compared with female students (P values < .05), but this gap closed in 2019 (P = .832). Beginning in 2022 and continuing in 2023, female high school students had a higher prevalence of current e-cigarette use compared with male students (P < .05).
Weighted percentage (95% CI) of US high school students using e-cigarettes in the past 30 days by sex, National Youth Tobacco Survey, 2014 to 2023.
Weighted percentage (95% CI) of US high school students using e-cigarettes in the past 30 days by sex, National Youth Tobacco Survey, 2014 to 2023.
A similar finding was observed using YRBS data (Fig 2). Between 2015 and 2017, male high school students had a higher prevalence of e-cigarette use (P values < .05), whereas prevalence was similar in 2019 (P = .249). However, by 2021, female students had a higher prevalence of e-cigarette use (P < .001). See Supplemental Table 4 for estimates and corresponding 95% CI.
Weighted percentage (95% CI) of US high school students using e-cigarettes in the past 30 days by sex, Youth Risk Behavioral Surveillance System, 2015 to 2021.
Weighted percentage (95% CI) of US high school students using e-cigarettes in the past 30 days by sex, Youth Risk Behavioral Surveillance System, 2015 to 2021.
Discussion
In recent years, a greater proportion of female high school students used e-cigarettes compared with male students, a reversal of historical sex differences in e-cigarette use before 2019. These findings were consistent across 2 national US surveys. Additional years of data are needed to confirm whether this new disparity will be a short- or long-term trend.
These findings have implications for clinicians and researchers. Improved pediatric screening for e-cigarette use and clinical intervention is needed.6 Understanding patterns of adolescent e-cigarette use, including use by sex, may help clinicians identify youth e-cigarette users and appropriately intervene. For example, the American Academy of Pediatrics offers resources to help pediatricians speak to youth about e-cigarette use.7 The relationship between e-cigarette use and sex appears to have changed during the coronavirus disease 2019 pandemic. During this time, female adolescents reported greater feelings of sadness or hopelessness than male adolescents.8 Moreover, a scoping review by Javed et al reported that e-cigarette use was associated with depression, suicidal ideation, and suicide attempts.9 Longitudinal research has suggested that depressive symptoms may predict subsequent e-cigarette use.10 Future research should examine changes in mental health among females as a potential driver of higher e-cigarette use among female adolescents. Researchers may also consider examining changes in other predictors of e-cigarette use, such as the introduction of new product designs and industry marketing tactics.
Dr Seidenberg conceptualized and designed the study, conducted the initial analyses, and drafted the initial manuscript; Ms Donovan helped draft the initial manuscript, critically reviewed and revised the manuscript; Mr Liu performed data analysis and critically reviewed the revised manuscript; Dr Kreslake critically reviewed and revised the manuscript; and all authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.
FUNDING: This research was funded by Truth Initiative.
CONFLICT OF INTEREST DISCLOSURES: The authors have indicated they have no conflicts of interest relevant to this article to disclose.
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