Frequency of Youth E-Cigarette and Tobacco Use Patterns in the United States: Measurement Precision Is Critical to Inform Public Health

Abstract

Introduction: E-cigarette use occurs with tobacco product use in youth.

Methods: Using the 2014 National Youth Tobacco Survey (NYTS), we examined past 30-day frequency of cigarette, cigar, smokeless, and e-cigarette use in the context of past 30-day and ever tobacco product use in US middle and high school students (N = 22 007). Frequency of product-specific use was examined by exclusive versus concurrent use with another product in the past 30 days (poly-use).

Results: In 2014, the majority (83%) of US middle and high school students had not used tobacco or e-cigarettes in the past 30 days. In the 9.3% of youth reporting any past 30-day e-cigarette use, 63% also reported using a tobacco product; among the 3.3% past 30-day exclusive e-cigarette users, about two-thirds (2.1%) had ever used combustible or non-combustible tobacco products and one-third (1.2%) had not. Few never tobacco users had used e-cigarettes on 10 or more days in the past month (absolute percent < 0.1%). Among past 30-day cigarette and smokeless users, the two highest frequency categories were 1-2 days and daily use; among past 30-day e-cigarette and cigar users, prevalence decreased with increasing frequency of use. The majority of past 30-day cigarette, cigar, smokeless, and e-cigarette users reported poly-use.

Conclusions: Prevalence estimates for a single product mask the complex patterns of frequency, temporality, and poly-use in youth. Two-thirds of past 30-day exclusive e-cigarette users have ever used tobacco. Poly-use is the dominant pattern of tobacco and e-cigarette use among US middle and high school students.

Implications: Our study highlights the complexity of tobacco use patterns in US middle and high school students. Future studies addressing the full public health impact of movement into or out of combustible tobacco use will require longitudinal data with appropriate measures of tobacco and e-cigarette product-specific use (eg, frequency and intensity), as well as adequate sample size and a sufficient number of waves to determine how use of individual products, like e-cigarettes, impact progression into or out of more stable patterns of tobacco and e-cigarette use.

Figure 1.

Distribution of tobacco and e-cigarette co-use among US middle and high school students (weighted); National Youth Tobacco Survey, 2014. Tobacco use categories are mutually exclusive. Ever use, no past 30-day use was defined as reporting ever use of any of the following products, but no use of any product in the past 30-days: cigarettes (including roll-your-own cigarettes), cigars, pipe, kreteks, hookah, flavored little cigars, flavored cigars (including clove cigars), bidis, smokeless tobacco, snus, dissolvable tobacco products, and e-cigarettes. Any combustible tobacco use was defined as endorsing past 30-day use of any of the following products: cigarettes (including roll-your-own cigarettes), cigars, pipe, kreteks, hookah, flavored little cigars, flavored cigars (including clove cigars), and bidis; past 30-day e-cigarette users were included in this category if they reported use of any of these combustible products. Non-combustible tobacco use was defined as past 30-day use of smokeless tobacco, snus, or dissolvable tobacco products, but no past 30-day combustible use; past 30-day e-cigarette users were included in this category if they reported use of any of these non-combustible products. Exclusive e-cigarette users reported only past 30-day use of e-cigarettes. Respondents who did not endorse use of any tobacco or e-cigarette product were coded to the “no past 30-day use” group.

Figure 2.

Distribution of tobacco and e-cigarette co-use among US middle and high school students who reported past 30-day e-cigarette use (weighted); National Youth Tobacco Survey, 2014. Tobacco use categories are mutually exclusive. Any combustible tobacco use was defined as endorsing past 30-day use of any of the following products: cigarettes (including roll-your-own cigarettes), cigars, pipe, kreteks, hookah, flavored little cigars, flavored cigars (including clove cigars), and bidis; past 30-day e-cigarette users were included in this category if they reported use of any of these combustible products. Non-combustible tobacco use was defined as past 30-day use of smokeless tobacco, snus, or dissolvable tobacco products, but no past 30-day combustible use; past 30-day e-cigarette users were included in this category if they reported use of any of these non-combustible products. Exclusive e-cigarette users reported only past 30-day use of e-cigarettes. Respondents who did not endorse use of any tobacco or e-cigarette product were coded to the “no past 30-day use” group.

Figure 3.

Frequency of cigarette, cigar, and smokeless tobacco and e-cigarette use among past 30-day US middle and high school student users (weighted); National Youth Tobacco Survey, 2014.