The Importance of Global Youth E-Cigarette Use Surveillance: Opportunities and Next Steps

Tobacco is a leading cause of preventable death, disease, and impoverishment globally^1,2 and an important public health challenge for assessment and intervention. Youth through young adulthood is the most important time to prevent uptake and intervene; US studies have found that 90% of cigarette smokers initiate smoking before age 18 years, and 99% initiate before age 25 years.³ Moving past experimentation, global studies have found that the average cigarette smoker begins regular use by age 15 years,⁴ again underscoring the importance of youth and young adulthood as a time for tobacco use surveillance and intervention. Historically, tobacco control research has focused on conventional combustible cigarettes; however, given the tobacco industry’s history and tactics, specifically in low- and middle-income countries,⁵ and the proliferation of novel tobacco and nicotine products in the United States and globally,¹ it is necessary to understand trends in the use of tobacco and nicotine products broadly. Product use assessed across countries and regions provides both important insight into concerted industry tactics and timely awareness of emerging products. The assessment of use of these products across countries can also aid in country-to-country cooperation. Tobacco use and associated health outcomes are a global epidemic; however, the majority of the burden of tobacco-related morbidity and mortality falls on low- and middle-income countries.² In response to the globalization of the tobacco epidemic, the World Health Organization (WHO) developed the Framework Convention on Tobacco Control, a global treaty establishing the dangers of tobacco and aimed at reducing its use. Subsequently, MPOWER, a policy package designed to assist countries with implementing Framework Convention on Tobacco Control, was launched, urging countries to monitor tobacco use and prevention; protect people from smoke; offer cessation support; warn about the dangers of tobacco; enforce bans on advertising, promotion, and sponsorship; and raise tobacco taxes.

E-CIGARETTE USE AND YOUTHS

Since their introduction to the US market, e-cigarettes have experienced a dramatic rise in use, particularly among youths and young adults. This alarming and rapid increase in use has been well documented in the United States.⁶ In an attempt to reduce use among youths and young adults, many US states and localities enacted policies that limit access to e-cigarettes, particularly flavored e-cigarettes. These trends in use and the response in the form of policies have not been limited to the United States. Recently, WHO published case studies highlighting various countries’ e-cigarette regulations, demonstrating the diversity of product availability and the policy landscape in Brazil, Canada, the Republic of Korea, and the United Kingdom.⁷ The long-term health risks of e-cigarettes are still largely unknown, and although they are sometimes recommended as a harm reduction cigarette cessation strategy, they are not currently reviewed or approved as cessation devices in the United States and many other countries. E-cigarette use by nicotine-naive youths poses many potential harms and should be actively avoided.

THE GLOBAL YOUTH TOBACCO SURVEY

The Global Youth Tobacco Survey (GYTS) is a school-based survey developed by WHO and the Centers for Disease Control and Prevention. The GYTS uses a standard methodology to collect data on youth tobacco use to inform and evaluate tobacco control and prevention efforts. The school-based survey of students aged 13 to 15 years has a core questionnaire with optional modules and questions based on country context.⁸ The WHO and the Centers for Disease Control and Prevention offer technical support to countries during the planning, implementation, and quality control phases of the survey, ensuring that the methodology and survey instrument are standardized across countries. The GYTS was initiated in 1999, and questions about e-cigarettes have been included as part of the core questionnaire since 2012. GYTS data are critical to monitor country progress toward evidence-based MPOWER measures. The standardized GYTS instrument and methodology ensure that data can be compared both across countries and over time. Many prior studies, including several recent ones,^9,10 have made use of this important survey.

In “Prevalence of E-Cigarette Use and Its Associated Factors Among Youths Aged 12 to 16 Years in 68 Countries and Territories: Global Youth Tobacco Survey 2012–2019,” Sun et al. (p. 650), from China and Switzerland, used the GYTS to present prevalence estimates of youth e-cigarette use from various countries as well as an exploration of associated factors through regression modeling. This work is critically important; by using the GYTS data with the same survey methodology and core questionnaire administered across countries, the authors present a clear comparison of e-cigarette use across different countries and regions. Previous work has been limited by different survey designs and instruments; however, this work reduces much of the background noise resulting from sampling and instrument effects. The authors included a host of important covariates in their regression modeling and also conducted sensitivity analyses to compare the usual threshold for current use (≥ 1 day in the past month) with higher thresholds that would be indicative of more regular use than experimentation (≥ 3 days in the past month, ≥ 6 days in the past month, ≥ 10 days in the past month), which are significant strengths.

There are some limitations to this piece. These prevalence estimates cannot be interpreted in a vacuum—although it is easy to note the largest differences in prevalence (1.9% of youths reported past-month e-cigarette use in Kazakhstan in 2014 compared with 33.2% in Guam in 2017), these cannot be interpreted without considering historical and cultural contexts and tobacco industry marketing and promotion activities in each country included. The authors used the most recent GYTS data available for each country for the 2012–2019 period. However, dramatic shifts in e-cigarette use and product availability occurred globally from 2012 to 2019, which makes direct comparisons across years and countries challenging. Current e-cigarette use among US high school students increased 10-fold between 2012 (2.8%¹¹) and 2019 (27.5%¹²); it is likely that many other countries experienced a similar dramatic upward trend in use in this time period. Although the estimates presented in this paper can be used as a general indicator for e-cigarette use in a country, without multiple years of data to assess, trendlines within countries, and a thorough understanding of the product landscape and tobacco industry marketing and promotion efforts in each included country, it is difficult to generalize without overinterpretation.

The article by Sun et al. has far-reaching implications. The findings can help inform tobacco regulation and education priorities for countries included, especially those with higher prevalence of youth e-cigarette use. For countries with higher youth e-cigarette use, additional data analysis and surveillance efforts are warranted to understand the scope of the use of these products and associated behaviors and health outcomes. For countries with relatively lower prevalence of youth e-cigarette use, this work can help shift tobacco control priorities toward other, more commonly used products to ensure the greatest possible benefit. This article helps to dispel the notion that e-cigarettes are only commonly used in wealthier countries, because the tobacco industry has a long history of targeting its marketing and promotion in low- and middle-income countries. Most importantly, however, this article illustrates the utility and unique value of GYTS and other global surveillance efforts in providing crucial multicountry analyses.