Adolescents and e-cigarettes: Objects of concern may appear larger than they are

Document analysis of the Foundation for a Smoke-Free World's scientific outputs and activities: a case study in contemporary tobacco industry agnogenesis

BACKGROUND

Tobacco corporation Philip Morris International launched the Foundation for a Smoke-Free World (FSFW), a purportedly independent scientific organisation, in 2017. We aimed to systematically investigate FSFW's activities and outputs, comparing these with previous industry attempts to influence science, as identified in the recently developed typology of corporate influence on science, the Science for Profit Model (SPM).

DESIGN

We prospectively collected data on FSFW over a 4-year period, 2017-2021, and used document analysis to assess whether FSFW's activities mirror practices tobacco and other industries have historically used to shape science in their own interests. We used the SPM as an analytical framework, working deductively to search for use of the strategies it identifies, and inductively to search for any additional strategies.

RESULTS

Marked similarities between FSFW's practices and previous corporate attempts to influence science were observed, including: producing tobacco industry-friendly research and opinion; obscuring industry involvement in science; funding third parties which denigrate science and scientists that may threaten industry profitability; and promoting tobacco industry credibility.

CONCLUSIONS

Our paper identifies FSFW as a new vehicle for agnogenesis, indicating that, over 70 years since the tobacco industry began to manipulate science, efforts to protect science from its interference remain inadequate. This, combined with growing evidence that other industries are engaging in similar practices, illustrates the urgent need to develop more robust systems to protect scientific integrity.

Optimal Taxation of Cigarettes and E-Cigarettes: Principles for Taxing Reduced-Harm Tobacco Products

As the tax base for traditional tobacco excise taxes continues to erode, policymakers have growing interest to expand taxation to novel and reduced-risk tobacco products. Chief among the latter are electronic nicotine delivery systems (ENDS; commonly known as e-cigarettes), although other reduced-risk tobacco products such as heated tobacco and smokeless tobacco products are also being considered for taxation. There are many possible rationales for taxing such products: to raise revenue, to correct for health externalities, to improve public health, to correct for internalities caused by irrationality or misinformation, and to redistribute income. Although each rationale leads to a different objective function, the conclusions regarding relative tax rates are largely the same. The relatively higher price elasticity of demand for e-cigarettes (compared to cigarettes) and the lower marginal harms from use imply in each case that taxes on e-cigarettes and other harm-reduced products should be relatively lower, and likely much lower, than those on cigarettes. Additional considerations concerning the policy goal of discouraging use of any tobacco product by youth are discussed as well.

College health providers' knowledge and confidence in addressing students' vaping: Evidence from a pilot study in New York State

Objective

This study examines the knowledge and confidence of college healthcare providers in discussing vaping with their college student populations.

Methods

This is a mixed-methods descriptive study using a sequential-explanatory approach, consisting of a cross-sectional, online survey followed by qualitative interviews. Survey data was collected from 50 college health providers located at 26 colleges in the 64-campus State University of New York system. Targeted semi-structured interviews (N = 11) were conducted by telephone with providers who completed the survey.

Results

Despite high reported levels of knowledge and confidence, few providers had participated in educational activities relative to vaping. There was evidence of misinformation about e-cigarettes, and they did not know what product (nicotine/cannabis) students typically vape.

Conclusions

Findings indicate a potential disconnect between providers' perceived and actual knowledge of college student vaping and demonstrate areas of opportunity to assist college health providers in comprehensively addressing vaping with their college student populations.

Innovation

College health providers played a key role in lowering rates of combustible cigarette smoking, but little is known about how they are now are communicating with college students about e-cigarette and cannabis vaping. This paper examines college health providers' knowledge, confidence, and training needs relative to vaping communications.

Exploring the gateway hypothesis of e-cigarettes and tobacco: a prospective replication study among adolescents in the Netherlands and Flanders

BACKGROUND

Studies demonstrated that adolescent e-cigarette use is associated with subsequent tobacco smoking, commonly referred to as the gateway effect. However, most studies only investigated gateways from e-cigarettes to tobacco smoking. This study replicates a cornerstone study revealing a positive association between both adolescent e-cigarette use and subsequent tobacco use; and tobacco and subsequent e-cigarette use in the Netherlands and Flanders.

DESIGN

The longitudinal design included baseline (n=2839) and 6-month (n=1276) and 12-month (n=1025) follow-up surveys among a school-based cohort (mean age: 13.62). Ten high schools were recruited as a convenience sample. The analyses involved (1) associations of baseline e-cigarette use and subsequent tobacco smoking among never smokers; (2) associations of e-cigarette use frequency at baseline and tobacco smoking frequency at follow-up; and (3) the association of baseline tobacco smoking and subsequent e-cigarette use among non-users of e-cigarettes.

FINDINGS

Consistent with prior findings, baseline e-cigarette use was associated with higher odds of tobacco smoking at 6-month (OR=1.89; 95% CI 1.05 to 3.37) and 12-month (OR=5.63; 95% CI 3.04 to 10.42) follow-ups. More frequent use of e-cigarettes at baseline was associated with more frequent smoking at follow-ups. Baseline tobacco smoking was associated with subsequent e-cigarette use (OR=3.10; 95% CI 1.58 to 6.06 at both follow-ups).

CONCLUSION

Our study replicated the positive relation between e-cigarette use and tobacco smoking in both directions for adolescents. This may mean that the gateway works in two directions, that e-cigarette and tobacco use share common risk factors, or that both mechanisms apply.

Effect of flavored E-cigarette bans in the United States: What does the evidence show?

The United States federal government, along with many state and local governments, have passed restrictions on electronic cigarette ("e-cigarette") sales with the stated purpose of preventing youth use of these products. The justification for these restrictions includes the argument that youth e-cigarette use will re-normalize youth smoking, leading to increased rates of cigarette smoking by teenagers. However, in this paper, we propose an evidence-based version of this model based on several years' worth of longitudinal and econometric research, which suggests that youth e-cigarette use has instead worked to replace a culture of youth smoking. From this analysis, we propose a re-evaluation of current policies surrounding e-cigarette sales so that declines in e-cigarette use will not come at the cost of increasing cigarette use among youth and adults.

Association of quarterly prevalence of e-cigarette use with ever regular smoking among young adults in England: a time-series analysis between 2007 and 2018

AIMS

To assess how changes in the prevalence of e-cigarette use among young adults have been associated with changes in the uptake of smoking in England between 2007 and 2018.

DESIGN

Time-series analysis of population trends with autoregressive integrated moving average with exogeneous input (ARIMAX models).

SETTING

England.

PARTICIPANTS

Data were aggregated quarterly on young adults aged 16-24 years (n = 37 105) taking part in the Smoking Toolkit Study.

MEASURES

In the primary analysis, prevalence of e-cigarette use was used to predict prevalence of ever regular smoking among those aged 16-24. Sensitivity analyses stratified the sample into those aged 16-17 and 18-24. Bayes' factors and robustness regions were calculated for non-significant findings [effect size beta coefficient (B) = 3.1].

FINDINGS

There was evidence for no association between the prevalence of e-cigarette use and ever regular smoking among those aged 16-24 [B = -0.015, 95% confidence interval (CI) = -0.046 to 0.016; P = 0.341; Bayes factor (BF) = 0.002]. Evidence for no association was also found in the stratified analysis among those aged 16-17 (B = 0.070, 95% CI -0.014 to 0.155, P = 0.102; BF = 0.015) and 18-24 (B = -0.021, 95% CI -0.053 to 0.011; P = 0.205; BF = 0.003). These findings were able to rule out percentage point increases or decreases in ever regular smoking prevalence greater than 0.31% or less than -0.03% for 16-17-year-olds and 0.01 or -0.08% for 18-24-year-olds for every 1%-point increase in e-cigarette prevalence.

CONCLUSION

Prevalence of e-cigarette use among the youth population in England does not appear to be associated with substantial increases or decreases in the prevalence of smoking uptake. Small associations cannot be ruled out.

Is Adolescent E-Cigarette Use Associated With Subsequent Smoking? A New Look

INTRODUCTION

Prospective studies have consistently reported a strong association between e-cigarette use and subsequent cigarette smoking, but many failed to adjust for important risk factors.

METHODS

Using longitudinal data from the Population Assessment of Tobacco and Health (PATH) Study, we employed multivariable logistic regressions to assess the adolescent vaping-to-smoking relationship, with four regressions (Models 1-4) sequentially adding more risk factors.Our sample included all waves (waves 1-5) of the PATH Study.

RESULTS

The association between ever e-cigarette use and subsequent cigarette smoking decreased substantially in magnitude when adding more control variables, including respondents' sociodemographic characteristics, exposure to tobacco users, cigarette susceptibility, and behavioral risk factors. Using the most recent data (waves 4-4.5 and waves 4.5-5), this association was not significant in the most complete model (Model 4). Using wave 4.5-5 data, the adjusted odds ratio (aOR) for ever e-cigarette use at initial wave and subsequent past 12-month smoking declined from 4.07 (95% confidence interval [CI, 2.86-5.81) in Model 1, adjusting only for sociodemographic characteristics, to 1.35 (95% CI, 0.84-2.16) in Model 4, adjusting for all potential risk factors. Similarly, the aOR of ever e-cigarette use and past 30-day smoking at wave 5 decreased from 3.26 (95% CI, 1.81-5.86) in Model 1 to 1.21 (95% CI, 0.59-2.48) with all covariates (Model 4).

CONCLUSIONS

Among adolescent never cigarette smokers, those who had ever used e-cigarettes at baseline, compared with never e-cigarette users, exhibited modest or non-significant increases in subsequent past 12-month or past 30-day smoking when adjusting for behavioral risk factors.

Adolescents' Use of Nicotine-Free and Nicotine E-Cigarettes: A Longitudinal Study of Vaping Transitions and Vaper Characteristics

INTRODUCTION

Although adolescents' nicotine addiction from e-cigarettes is a concern, few studies differentiate between vaping with and without nicotine. This study examines the prevalence of nicotine and nicotine-free vaping, maps transitions between vaping behaviors, and assesses differences in the personal characteristics of vapers in a sample of Norwegian adolescents.

AIMS AND METHODS

Data came from a nationwide longitudinal study of adolescents (n = 2018) conducted in 2017 (T1), 2018 (T2), and 2019 (T3) (mean age: 14.2, 15.0, and 16.2). Using an online questionnaire, we measured vaping with and without nicotine, snus use, smoking, sensation-seeking, conduct problems, and levels of depression.

RESULTS

Past 12-month vaping prevalence was stable (12%, 13%, and 15%). Among adolescents reporting vaping at T1, 66% had used e-cigarettes without nicotine, 22% with nicotine, and 12% were unsure of nicotine content. Individual vaping trajectories were unstable: of nicotine-free vapers, 54% became non-users, while 14% became nicotine vapers from T1 to T2. From T2 to T3, 50% became non-users, while 17% became nicotine vapers. Of nicotine vapers, 39% became non-users from T1 to T2, while 46% became non-users from T2 to T3. Compared to nicotine-free vapers, nicotine vapers had more conduct problems (mean = 3.67 vs 2.17), had more symptoms of depression (mean = 11.38 vs 6.95), and comprised more past 30-day snus users (33% vs 14%) and cigarette users (33% vs 9%).

CONCLUSIONS

Adolescent vapers most commonly used e-cigarettes without nicotine, few of these transitioned into nicotine vaping, and a majority became non-users. Nicotine vapers were more likely to use other tobacco products and have more conduct problems and symptoms of depression compared to nicotine-free vapers.

IMPLICATIONS

Reporting the prevalence of nicotine-free vaping is critical for assessing nicotine exposure and subsequent risks of nicotine addiction. This multi-cohort longitudinal study showed that use of nicotine-free e-cigarettes is common among young vapers in Norway. Adolescents' vaping patterns-both with and without nicotine-are generally temporal and experimental. Despite the majority of nicotine vapers becoming non-users, they are characterized by having more conduct problems and poorer mental health, and they more often used other tobacco products.

Comparison of e-cigarette use prevalence and frequency by smoking status among youth in the United States, 2014-19

BACKGROUND AND AIMS

Reports of youth e-cigarette use often do not disaggregate by underlying smoking status. This study compared annual 2014-19 youth estimates of past 30-day e-cigarette use prevalence and frequency by smoking status in the United States.

DESIGN

Nationally representative, cross-sectional, school-based survey [National Youth Tobacco Surveys (NYTS)]. General linear models accounting for complex survey design compared e-cigarette use prevalence by smoking status by year, overall and stratified by frequency, separately for high school (HS) and middle school (MS) students. The 2019 survey was analyzed separately because of its change in survey methodology.

SETTING

MSs and HSs in the United States.

PARTICIPANTS

A total of 116 704 students from 1268 schools, ages 9-19.

MEASUREMENTS

Students self-reported (paper 2014-18, electronic 2019) ever and past 30-day (current) use of e-cigarettes and cigarettes, as well as frequent use (20-30 days of month).

FINDINGS

From 2014 to 2018, current e-cigarette use prevalence increased among never, current and former smokers in HS, but only among never and current smokers in MS (each P-value < 0.001). E-cigarette use increases for current HS smokers were primarily among frequent e-cigarette users. In 2018, the absolute number of HS frequent users who were never or former smokers (420 000 combined) surpassed current smokers (370 000). In 2019, current e-cigarette use prevalence for never, former and current smokers was 17.5% [95% confidence interval (CI) = 16.0-19.0], 53.6% (95% CI = 45.2-61.9) and 85.8% (95% CI = 81.6-89.9) for HS students, respectively, and 6.8% (95% CI = 5.9-7.7), 40.8% (95% CI = 34.7-47.0) and 78.0% (95% CI = 71.9-84.2) for MS students. That year, the number of HS never (420 000) and former smokers (570 000) using e-cigarettes frequently eclipsed that of current smokers (390 000).

CONCLUSIONS

E-cigarette use prevalence and frequency among youth vary by smoking status, with highest levels of use among current smokers. However frequent e-cigarette use among never smokers and former smokers has increased.

Balancing Consideration of the Risks and Benefits of E-Cigarettes

The topic of e-cigarettes is controversial. Opponents focus on e-cigarettes' risks for young people, while supporters emphasize the potential for e-cigarettes to assist smokers in quitting smoking. Most US health organizations, media coverage, and policymakers have focused primarily on risks to youths. Because of their messaging, much of the public-including most smokers-now consider e-cigarette use as dangerous as or more dangerous than smoking. By contrast, the National Academies of Science, Engineering, and Medicine concluded that e-cigarette use is likely far less hazardous than smoking. Policies intended to reduce adolescent vaping may also reduce adult smokers' use of e-cigarettes in quit attempts. Because evidence indicates that e-cigarette use can increase the odds of quitting smoking, many scientists, including this essay's authors, encourage the health community, media, and policymakers to more carefully weigh vaping's potential to reduce adult smoking-attributable mortality. We review the health risks of e-cigarette use, the likelihood that vaping increases smoking cessation, concerns about youth vaping, and the need to balance valid concerns about risks to youths with the potential benefits of increasing adult smoking cessation.

Sociodemographic Patterns of Exclusive and Dual Use of ENDS and Menthol/Non-Menthol Cigarettes among US Youth (Ages 15-17) Using Two Nationally Representative Surveys (2013-2017)

The use of electronic nicotine delivery systems (ENDS) among youth in the United States has increased rapidly in the past decade. Simultaneously, while youth cigarette smoking has declined considerably, youth are still more likely to use menthol cigarettes than any other age group. We used nationally representative data on 15–17-year-olds from the Population Assessment of Tobacco and Health (PATH) Study and the National Youth Tobacco Survey (NYTS) (2013–2017) to better understand current cigarette (by menthol flavoring) and ENDS use in the US. We calculated weighted population prevalence estimates across years for multiple patterns of current cigarette and ENDS use (i.e., exclusive menthol cigarette, exclusive non-menthol cigarette, exclusive ENDS, dual ENDS and menthol cigarette, and dual ENDS and non-menthol cigarette) by sex, race/ethnicity, parental education level, household income, and homeownership. Overall, both exclusive menthol and non-menthol cigarette use declined from 2013–2017. Exclusive ENDS use increased, particularly among youth who were non-Hispanic White or had a higher socioeconomic status (measured by parental education, household income, and homeownership). Dual use of ENDS with either menthol or non-menthol cigarettes did not change significantly. Monitoring changes in these sociodemographic patterns will help inform future youth tobacco prevention strategies.

From gateways to multilinear connections: A qualitative longitudinal investigation of the relationships between vaping and smoking among adolescent users

BACKGROUND

The international growth of e-cigarette use has been accompanied by a corresponding concern that e-cigarettes will act as a 'gateway' to smoking and the use of other drugs. Taking these concerns as our point of departure, we explore the relationships between vaping and smoking among a cohort of young people.

METHODS

Qualitative longitudinal methods with a diverse sample of 36 14-18-year olds from the UK city of Leicester. A total of 66 depth interviews conducted across two phases separated by 6-12 months. The interviews were recorded, transcribed verbatim and thematically analysed.

FINDINGS

We highlight a complex 'tangle' of connections between substances/risk behaviours recounted to us by our adolescent study participants, including multiple and multilinear relationships between vaping and smoking. These findings problematise some of the core axioms of the notion of gateways as an explanatory model of causality and sequential connection between smoking and vaping. They also throw into question gateway logics more fundamentally. While many of our study participants themselves consciously invoked ideas of 'gateway effects', the accounts they produced repeatedly disrupted the logics of connection (between e-cigarettes and smoking; one set of behaviours and another) presupposed in gateway theory and our own early lines of questioning. Accordingly, we explore how cultural understandings of gateway effects are invoked by users in accounting for their vaping and smoking behaviours, noting the potential influence of these ideas upon the very processes they are understood to apprehend.

CONCLUSION

Our findings suggest there is a case to be made to reinforce the distinctiveness of tobacco and e-cigarettes in the life-worlds of young people to avoid naturalising a 'gateway' logic of connection that might ultimately inform the associative logic of young users themselves, and potentially the development of their usage careers.

A conceptual framework for assessing the public health effects from snus and novel non-combustible nicotine products

Objective:

The tobacco industry plans to base their future earnings on the production of non-combustible nicotine products. These might replace or come in addition to the more harmful cigarettes that historically have dominated the nicotine market in the Nordic countries. The authorities in each country must decide whether the products should have market access and, in that case, how strictly they should be regulated. Our aim is to present a framework that can assist the health authorities to make a regulation where benefits will outweigh the harms.

Method:

In a public health perspective, health gains from substitution must be weighed against the health loss from additional use. The main elements of the weighing will be based on the information about the absolute risk of the products, their relative risk compared to conventional cigarettes and how the users are composed according to smoking status. We apply the framework on snus as used in Norway – a product with an established usage pattern and epidemiologically assessed health risks.

Results:

The framework consists of (i) a comprehensive set of specific user patterns that may result in health deterioration and user patterns that may result in health benefits, (ii) an estimation of the number of people with health-augmenting and health-impairing user patterns, respectively, and (iii) an estimation of the degree of health deterioration or health benefit that will affect the persons with the different user patterns.

Conclusion:

The net effect on public health will appear as an overall result of the number of people with positive and negative user patterns, respectively, in combination with the magnitude of the change in health status these people will experience. The use of an explicit framework highlights how a political decision may affect nicotine use and health-related outcomes. The framework breaks open a large and complex question into smaller pieces and requires the authorities to expose and explain the kind of evidence and reasoning behind regulations of novel nicotine products.

Experimenting first with e-cigarettes versus first with cigarettes and transition to daily cigarette use among adolescents: the crucial effect of age at first experiment

BACKGROUND AND AIMS

Most studies in English-speaking countries have found a positive association between e-cigarette experimentation and subsequent daily tobacco smoking among adolescents. However, this result may not be valid in other cultural contexts; in addition, few studies have assessed whether this association varies with the subject' age at the time of e-cigarette experimentation. This study aimed to estimate the association between experimenting first with e-cigarette (rather than tobacco) and subsequent daily smoking according to age at the time of experimentation.

DESIGN

Secondary analysis; risk ratios (RRs) computed using modified Poisson regressions with inverse probability weighting.

SETTING

A cross-sectional nation-wide representative survey performed in 2017 in France.

PARTICIPANTS

French adolescents (n = 24 111), aged 17 to 18.5 years, who had previously experimented with either e-cigarettes or tobacco.

MEASURES

Exposure was defined as the experimentation with e-cigarettes first (whether or not followed by experimentation with tobacco); the outcome as daily tobacco smoking at the time of data collection. Gender, age, literacy, socio-economic status, pre-exposure repeat school years and experimentation with drunkeness, 3 licit and 8 illicit drugs were adjusted for. Uncertainties about the sequence of events defining exposure were handled by the definition of three patterns of exposure, to avoid a misclassification bias.

FINDINGS

Exposure reduced the risk of transition to daily smoking: RR = 0.58, 95% confidence interval (CI) = 0.54, 0.62. This effect increased in a linear manner with age at exposure (RR = 0.87, 95% CI = 0.78; 0.98 for 1 year, P < 0.001): from RR = 1.30, 95% CI = 1.09; 1.54 at age 9 to RR = 0.38, 95% CI = 0.32; 0.45 at age 17.

CONCLUSIONS

Experimenting with e-cigarettes first (as opposed to tobacco first) appears to be associated with a reduction in the risk of daily tobacco smoking among French adolescents aged 17-18.5, but this risk varies negatively with age at experimentation, and early e-cigarette experimenters are at higher risk.

Applying the Population Health Standard to the Regulation of Electronic Nicotine Delivery Systems

Regulatory authorities have devoted increasing attention and resources to a range of issues surrounding the regulation of novel nicotine and tobacco products. This review highlights the inherent complexity of evaluating prospective policies that pertain to products that heat solutions containing nicotine, but not tobacco leaf, sometimes referred to as electronic nicotine delivery systems (ENDS). The US Food and Drug Administration (FDA) is compelled to incorporate a set of public health criteria in their decision making, collectively referred to as the Population Health Standard. Adherence to this standard is necessary to estimate the impact of prospective ENDS policy decisions on net population harm associated with nontherapeutic nicotine products. For policies that are expected to decrease or increase ENDS use, application of the Population Health Standard requires a comprehensive assessment of the status quo impact of ENDS use on population health. Accordingly, this review first assesses the state of the evidence on the direct harms of ENDS and the indirect effects of ENDS use on smoking, particularly rates of initiation and cessation. After that, the example of flavor restrictions is used to demonstrate the further considerations that are involved in applying the Population Health Standard to a prospective ENDS policy. Implications: This narrative review aims to inform regulatory considerations about ENDS through the prism of the Population Health Standard. More specifically, this review (1) describes and explains the importance of this approach; (2) provides guidance on evaluating the state of the evidence linking ENDS to the net population harm associated with nontherapeutic nicotine products; and (3) illustrates how this framework can inform policymaking using the example of flavor restrictions.

Trajectories and determinants of adolescents' nicotine product use risk among U.S. adolescents in a nationally representative sample of longitudinal cohort

INTRODUCTION

To understand the heterogeneous longitudinal trends in adolescent nicotine product use risk, we investigated the trajectories and determinants of nicotine product use among adolescents.

METHODS

Using Waves 1-4 (Years 2013-2018) data of the Population Assessment of Tobacco and Health Study, we conducted group-based trajectory modeling to identify groups of individuals who followed homogeneous trajectories of nicotine product use risk over time and weighted multinomial logistic regression to examine relative risk ratios (RRRs) of different levels of predictors of group membership in each identified trajectory.

RESULTS

For adolescents, who were 12-17 years old at baseline (N = 10,086), 5 trajectory groups emerged: (1) nonusers (73.7%); (2) stable low to moderate risk of developing poly use (5.0%); (3) gradual increase in risk of poly use (12.8%); (4) rapid linear increase in risk of poly use until Wave 3 and then plateauing for cigarettes or slightly diminishing for e-cigarettes and other tobacco products at Wave 4 (4.6%); and (5) stable moderate to high risk of poly use (3.9%). Adolescents who used social network services daily at Wave 1 were more likely to belong to each of the four trajectory groups compared to nonusers (RRRs ranging from 1.43 to 2.04).

CONCLUSIONS

The current study findings imply that the majority of adolescents who initiated any nicotine product use have an elevated risk of transitioning to poly users. Risk and protective factors for different risk patterns are discussed.

Youth Vaping and Tobacco Use in Context in the United States: Results From the 2018 National Youth Tobacco Survey

INTRODUCTION

According to the National Youth Tobacco Survey (NYTS), youth e-cigarette use (vaping) rose between 2017 and 2018. Frequency of vaping and concurrent past 30-day (p30d) use of e-cigarettes and tobacco products have not been reported.

METHODS

We analyzed the 2018 NYTS (N = 20 189) for vaping among all students (middle and high school; 6-12th grades; 9-19 years old) by frequency of vaping, exclusive vaping, p30d poly-product use (vaping and use of one or more tobacco product), and any past tobacco product use.

RESULTS

In 2018, 81.4% of students had not used any tobacco or vapor product in the p30d, and 86.2% had not vaped in the p30d. Among all students, of the 13.8% vaped in the p30d, just over half vaped on ≤5 days (7.0%), and roughly a quarter each vaped on 6-19 days (3.2%) and on 20+ days (3.6%). Almost three quarters of p30d vapers (9.9%) reported past or concurrent tobacco use and the remainder (3.9%) were tobacco naïve. 2.8% of students were tobacco naïve and vaped on ≤5 days; 0.7% were tobacco-naïve and vaped on 6-19 days, and 0.4% were tobacco-naïve and vaped on 20+ days.

CONCLUSIONS

Vaping increased among US youth in 2018 over 2017. The increases are characterized by patterns of low p30d vaping frequency and high poly-product use, and a low prevalence of vaping among more frequent but tobacco naïve vapers.

IMPLICATIONS

Results underscore the importance of including the full context of use patterns. The majority of vapers (60.0%-88.9% by use frequency) were concurrent p30d or ever tobacco users. About 4% of students were tobacco naïve and vaped in the p30d, but few (0.4%) vaped regularly on 20 or more days. Reporting youth vaping data with frequency and tobacco product co-use will give public health decision-makers the best possible information to protect public health.

A Magic Bullet? The Potential Impact of E-Cigarettes on the Toll of Cigarette Smoking

INTRODUCTION

We examine the proportion of US smoking-produced mortality that e-cigarettes might eliminate under assumptions regarding vaping's ability to increase smoking cessation, vaping's health risks, and the possibility that vaping will increase smoking among young people.

METHODS

We employ a dynamic population simulation model that tracks individuals from ages 0 to 110, differentiated by gender and smoking status. Using data from the US Census, the National Vital Statistics Reports, Cancer Prevention Study II, and the National Health Interview Survey, we estimate the number of smoking-related life-years lost (LYL) from 2018 to 2100 in a no-vaping scenario. We then compare results for model runs that assess the impact of vaping under a variety of assumptions.

RESULTS

The combination of assumptions produces 360 possible scenarios. 357 (99%) yield positive estimates of life-years saved (LYS) due to vaping by 2100, from 143 000 to 65 million. Most scenarios result in millions of individuals quitting smoking due to vaping. On average, vaping-induced quitters gain an extra 1.2-2.0 years of life compared to smokers who quit without vaping. The impact of vaping is greatest when it most helps smokers who otherwise have the greatest difficulty quitting smoking. While the numbers of LYS are generally large across all scenarios, they often represent a small fraction of the toll of smoking.

CONCLUSIONS

Vaping is highly likely to reduce smoking-produced mortality. Still, vaping is not "the" answer to the public health crisis created by smoking. Rather, it may well be a tool to add to the armamentarium of effective tobacco control measures.

IMPLICATIONS

E-cigarettes hold the potential to reduce cigarette smoking's enormous toll. By itself, however, tobacco harm reduction, as embodied in vaping, is no magic bullet. Going forward, tobacco control will require vigilant application of the evidence-based measures that have brought us so much success in combatting smoking. It will require, as well, the search for and adoption of novel means of attacking the remaining problem. Harm reduction can, and many would say should, be a part of the complex formula that will eventually bring about the demise of smoking.

Critical appraisal of the European Union Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) Preliminary Opinion on electronic cigarettes

BACKGROUND

In preparation for the 2021 revision of the European Union Tobacco Products Directive, the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) has posted its Preliminary Opinion on Electronic Cigarettes. They concluded that e-cigarettes only achieve a sub-optimal level of protection of human health. In this paper, we provide evidence that the Opinion's conclusions are not adequately backed up by scientific evidence and did not discuss the potential health benefits of using alternative combustion-free nicotine-containing products as substitute for tobacco cigarettes.

METHODS

Searches for articles were conducted in PubMed and by citation chasing in Google Scholar. Articles were also retrieved with a review of references in major publications. Primary data from World Health Organization surveys, the conclusions of reviews, and peer-reviewed non-industry studies were cited to address errors and omissions identified in the Opinion.

RESULTS

The Opinion omitted reporting on the individual and population health benefits of the substitution of e-cigarettes (ENDS) for cigarette smoking. Alternative hypotheses to the gateway theory were not evaluated. Its assessment of cardiovascular risk is contradicted by numerous reviews. It cites ever-use data that do not represent current patterns of use. It did not report non-nicotine use. It presented erroneous statements on trends in ENDS prevalence. It over-emphasized the role of flavours in youth ENDS initiation. It did not discuss cessation in sufficient length.

CONCLUSIONS

For the delivery of a robust and comprehensive final report, the members of the Working Group of the Scientific Committee on Health, Environmental and Emerging Risks will need to consider (1) the potential health benefits of ENDS substitution for cigarette smoking, (2) alternative hypotheses and contradictory studies on the gateway effect, (3) its assessment of cardiovascular risk, (4) the measurements of frequency of use, (5) non-nicotine use, (6) the role of flavours, and (7) a fulsome discussion of cessation.

Association of initial e-cigarette and other tobacco product use with subsequent cigarette smoking in adolescents: a cross-sectional, matched control study

INTRODUCTION

This study assessed whether initiating e-cigarette use increases the uptake of cigarette smoking in US adolescents compared with behavioural and synthetic controls.

METHODS

Data come from 78 265 adolescents in the National Youth Tobacco Survey (2014-2017) of whom 38 630 provided information about the first tobacco product they had used in 2014/15. Ever, past 30 day and established (30 day use and 100+ lifetime cigarettes) cigarette smoking was compared in adolescents who first used an e-cigarette (exposure group), a non-cigarette combustible (CT) or other non-combustible tobacco (NT) product (behavioural controls), and propensity score matched adolescents without initial e-cigarette use (synthetic controls).

RESULTS

Relative to behavioural controls, adolescents who tried e-cigarettes first were less likely to have ever smoked cigarettes (26% vs CT (42.4%; OR 0.48, 95% CI 0.40 to 0.57), or NT initiators (52.7%; OR 0.32, 95% CI 0.26 to 0.39)), to be past 30 day (6% vs CT (11.9%; OR 0.48, 95% CI 0.36 to 0.62), or NT initiators (20.0%; OR 0.26, 95% CI 0.19 to 0.35)) or be established cigarette smokers (0.7% vs CT (3.9%; OR 0.17, 95% CI 0.10 to 0.30), or NT initiators (8.4%; OR 0.08, 95% CI 0.04 to 0.13)). E-cigarette initiators were also less likely than synthetic controls (without initial e-cigarette use) to have ever smoked cigarettes (OR 0.76, 95% CI 0.62 to 0.93), be past 30 day (OR 0.71, 95% CI 0.55 to 0.91) or be established cigarette smokers (OR 0.26, 95% CI 0.13 to 0.51).

CONCLUSION

Less than 1% of US adolescents who use e-cigarettes first were established cigarette smokers. They were less likely to be smokers than adolescents who tried other combustible or non-combustible tobacco products first and propensity score matched adolescents without initial e-cigarette use.

The "gateway" effect of e-cigarettes may be explained by a genetic liability to risk-taking

Wayne Hall and Gary Chan discuss Jasmine Khouja and co-workers' accompanying study on genetic susceptibility to tobacco smoking initiation and e-cigarette use.

Correlates of Awareness and Use of Heated Tobacco Products in a Sample of US Young Adults in 2018-2019

INTRODUCTION

Tobacco companies have devoted increased resources in recent years to developing and marketing heated tobacco products (HTPs) as alternatives to combustible products like cigarettes. However, little is known about correlates of awareness and use of these products in American young adults.

METHODS

Two thousand four hundred ninety-seven young adults (mean age = 21.6) completed survey items on HTP awareness and lifetime use in 2018-2019. Logistic regression models compared young adults who were (1) unaware of HTPs (reference group) with those who were, (2) aware of HTPs, and (3) had ever used HTPs on demographic, tobacco, and other substance use characteristics. Among current smokers, these groups were compared on cigarette use, dependence, and readiness to quit.

RESULTS

Approximately 12% of respondents (n = 293) were aware of HTPs, and 5% (n = 134) reported lifetime HTP use. Controlling for demographics, HTP awareness and use were both associated with greater use of all types of tobacco products, number of different tobacco products, and use of marijuana and other drugs. Among current smokers, HTP awareness and use correlated with heavier cigarette consumption, greater dependence, and past-month marijuana use, but not with recent quit attempts or thinking about quitting cigarettes.

CONCLUSIONS

Awareness and use of HTPs among young adults were associated with greater use of tobacco products and other substances and, among current smokers, with greater cigarette dependence (but not cessation-related factors). As these products become increasingly available in the United States, additional surveillance and monitoring activities are needed to better understand use patterns, consequences, and reasons for using HTPs.

IMPLICATIONS

Few studies have examined factors associated with awareness and use of heated tobacco products (HTPs) among US young adults. HTP awareness and lifetime use correlated with a range of factors, including male gender, white race/ethnicity, and tobacco and other substance use. Lifetime use of HTPs was low (5%); most lifetime HTP users reported history of other tobacco use, but a sizeable minority (14%) reported no other tobacco product use history. Among current cigarette smokers, cigarette dependence, poly-tobacco use, and marijuana use-but not cigarette cessation attempts or contemplation-were associated with greater likelihood of awareness and use of HTPs.

Trends in E-Cigarette Use by Age Group and Combustible Cigarette Smoking Histories, U.S. Adults, 2014-2018

INTRODUCTION

The trends in e-cigarette prevalence and population count of users according to cigarette smoking histories are unknown. These data are needed to inform public health actions against a rapidly changing U.S. e-cigarette market.

METHODS

Data collected between 2014 and 2018 (analyzed in 2020) from cross-sectional, nationally representative National Health Interview Surveys were used to estimate current e-cigarette prevalence, adjusted prevalence differences (percentage points), and population counts of users. Analyses were stratified by age group (younger, 18-29 years, n=25,445; middle age, 30-49 years, n=47,745; older, ≥50 years, n=79,517) and cigarette smoking histories (current smokers, recent quitters [quit <1 year ago], near-term quitters [quit 1-8 years ago], long-term quitters [quit >8 years ago], never smokers).

RESULTS

Among younger adults, e-cigarette use increased in all groups of smokers, with notable increases between 2014 and 2018 among never smokers (1.3%-3.3%, adjusted prevalence difference=2%, p<0.001) and near-term quitters (9.1%-19.2%, adjusted prevalence difference=8.8%, p=0.024). Conversely, the only substantial increase in e-cigarette use between 2014 and 2018 among middle-aged (5.8%-14.4%, adjusted prevalence difference=8.2%, p<0.001) and older (6.3%-9.5%, adjusted prevalence difference=3.3%, p=0.045) adults was among near-term quitters. The largest absolute population increase in e-cigarette users between 2014 and 2018 was among younger-adult never smokers (0.49-1.35 million), followed by near-term quitters among middle-aged (0.36-0.95 million), younger (0.23-0.57 million), and older (0.35-0.50 million) adults.

CONCLUSIONS

The continuous increase among younger-adult never smokers suggests a rise in primary nicotine initiation with e-cigarettes. The concomitant increase among near-term quitters of all age groups suggests continuing e-cigarette use among smokers who may have switched from cigarettes previously.

Trends in Social Norms Towards Smoking Between 2002 and 2015 Among Daily Smokers: Findings From the International Tobacco Control Four Country Survey (ITC 4C)

OBJECTIVE

To assess trends in daily smokers' social norms and opinions of smoking between 2002 and 2015 in Canada, the United States, the United Kingdom, and Australia.

METHOD

Data were from wave 1 (2002) to wave 9 (2013-2015) of the longitudinal International Tobacco Control Four Country Survey (Canada, the United States, the United Kingdom, Australia), involving 23 831 adult daily smokers. Generalized estimating equation logistic regression models, adjusted for demographics and survey design effects, assessed associations of wave and country with outcomes: (A) over half of five closest friends smoke, (B) agreeing that people important to you believe you should not smoke, (C) agreeing that society disapproves of smoking, and (D) negative opinion of smoking.

RESULTS

Between 2002 and 2015, adjusting for covariates, (A) over half of five closest friends smoke did not change (56% vs. 55%; adjusted odds ratio [AOR] = 0.95 [95% Confidence Interval = 0.85-1.07]), (B) agreeing that people important to you believe you should not smoke generally decreased (89% vs. 82%; AOR = 0.54 [0.46-0.64]) despite an increase around 2006-2007, (C) agreeing that society disapproves of smoking increased between 2002 and 2006-2007 (83% vs. 87%; AOR = 1.38 [1.24-1.54]) then decreased until 2013-2015 (78%; AOR = 0.74 [0.63-0.88]), and (D) negative opinion of smoking decreased between 2002 and 2010-2011 (54% vs. 49%; AOR = 0.83 [0.75-0.91]) despite an increase around 2005-2006 and at the final wave (2013-2015). Except friend smoking, Canada had the greatest, and the United Kingdom the lowest, antismoking social norms and opinions.

CONCLUSIONS

Except friend smoking and opinion of smoking, daily smokers' social norms became less antismoking between 2002 and 2015 despite increases around 2006-2007. Several potential explanations are discussed yet remain undetermined.

IMPLICATIONS

Increasingly comprehensive tobacco control policies alongside decreasing smoking prevalence in Canada, the United States, the United Kingdom, and Australia have led to the assumption that smoking has become denormalized in these countries. Absent from the literature is any formal assessment of social norms towards smoking over time. Contrary to our hypotheses, this study found that the injunctive social norms of daily smokers became less antismoking between 2002 and 2015, despite increases around 2006-2007. There was no change over time in the proportion of daily smokers who report that over half of their five closest friends smoke.

Pathways of Nicotine Product Use: A Qualitative Study of Youth and Young Adults in California

INTRODUCTION

Existing research on youth's adoption of alternative nicotine delivery systems (ANDS) has focused on identifying pathways of nicotine product use, specifically examining whether vaping encourages progression to smoking. Few studies have considered other pathways of initiation. Qualitative studies suggest that meanings of vaping vary significantly, suggestive of the need for a more nuanced understanding of the role of vaping for youth with different pathways into vaping and smoking.

METHODS

We conducted in-depth qualitative interviews with 49 Californian youth between 15 and 25 years old who reported ever vaping nicotine to gain a deeper understanding of their initiation pathways of vaping and smoking, paying special attention to youth's experiences and reasons for ANDS initiation and use. Categorizing participants into initiation pathways by self-reported use and age of initiation of ANDS and cigarettes, we then compared the meaning and role of vaping across three distinct pathways of use: (1) smoking to vaping, (2) vaping to smoking, and (3) vaping only.

RESULTS

The most common pathway reported was smoking to vaping (74%), eight participants began vaping before smoking, and five participants reported only vaping but never smoking. Analysis of participants' narratives emphasized that youth in our study, regardless of initiation pathway, were generally aware of the health consequences of smoking and negotiated their use of nicotine products considering relative risks.

CONCLUSION

Findings from this study suggest that ANDS serve as a transitional tool for youth who are keenly aware of the health consequences of smoking, thus challenging conventional discourses about ANDS as a threat to youth's health.

IMPLICATIONS

This qualitative study queries concerns about the potential of alternative nicotine delivery systems (ANDS) to serve as a gateway into cigarette smoking for youth and young adults. Findings suggest that most of the youth participants discussed and considered relative risks in their pathways of initiation, highlighting the need to acknowledge harm reduction in constructing public health messaging and policies for smoking cessation.

Patterns of E-Cigarette Use Among Youth and Young Adults: Review of the Impact of E-Cigarettes on Cigarette Smoking

There is concern that e-cigarette use among youth and young adults (YAs) may lead to future cigarette or other combustible tobacco product use. A synthesis of the literature on this topic is needed because existing longitudinal studies are limited in number and not consistent in their conclusions. We conducted a search in PubMed through December 31, 2017 for peer-reviewed studies related to e-cigarette patterns of use. Of 588 relevant studies, 26 had a youth or YA sample, were longitudinal in design, and assessed e-cigarette use at baseline and cigarette smoking at follow-up. Most studies followed a sample over time and compared cigarette smoking at follow-up between baseline e-cigarette users and nonusers. Other studies examined the difference at follow-up in cigarette smoking status among smokers according to e-cigarette use at baseline. Results suggest that, among never smokers, e-cigarette use is associated with the future (6 months to 2.5 years) cigarette trial; however, firm conclusions cannot be drawn because of limitations including small sample size, measurement of experimental use (ie, ever use, past 30-day use) rather than established use, and inadequate controls for potentially confounding variables. Conclusions also cannot be drawn from studies examining the impact of e-cigarette use among smokers due to the limited number of studies and additional limitations. A comprehensive understanding of this literature is needed to inform policy makers and consumers for evidence-based decision-making and to guide future research on e-cigarette use among youth and young adults.

IMPLICATIONS

The present article provides a review of the impact of e-cigarette use on subsequent cigarette smoking among youth and YAs. Studies presented here suggest that e-cigarette use among nonsmokers is associated with subsequent cigarette smoking, but study designs are subject to numerous limitations. Future research should focus on addressing the characteristics that put youth and YAs at the risk of using either product and how appeal and accessibility of these products are related to product use in order to inform future policy-making.

Disentangling Within- and Between-Person Effects of Shared Risk Factors on E-cigarette and Cigarette Use Trajectories From Late Adolescence to Young Adulthood

BACKGROUND

Longitudinal studies report associations between use of electronic cigarettes (ECs) and cigarettes over time among young people, but do not distinguish within- from between-person effects, which complicates interpretation of findings. Further, the role of shared risk factors, such as substance use and mental health, in explaining longitudinal associations between EC and cigarette use remains unclear. This study used within- and between-person analyses to assess longitudinal associations between youths' EC and cigarette use and shared risk factors.

METHODS

Between 2015 and 2017, 2039 youths completed three Web-based surveys, allowing us to model EC and cigarette use from ages 16 to 20. Auto-regressive latent growth models with structured residuals (ALT-SR) examined both between-person and within-person associations between past-month frequency of EC use, cigarette use, and third variables (alcohol and marijuana use, mental health symptoms) over time.

RESULTS

Models revealed robust reciprocal associations between EC and cigarette use, such that more frequent EC use at one time predicted more frequent cigarette use at the subsequent time, and vice versa. Between-person analyses showed associations between shared risk factors and both EC and cigarette use. However, shared risk factors did not predict frequency of subsequent EC and cigarette use in within-person analyses.

CONCLUSIONS

Findings add to a growing body of research suggesting that EC use among youth is prospectively associated with progression toward greater cigarette use. Shared risk factors may help explain differences in EC and cigarette use patterns between young people, but do not appear to influence longitudinal trajectories of EC and cigarette use within individuals.

IMPLICATIONS

This study examined within- and between-person associations between e-cigarette use, cigarette use, and shared risk factors (alcohol use, marijuana use, mental health symptoms) in a longitudinal cohort of youths. Within- and between-person analyses revealed reciprocal prospective associations between e-cigarette and cigarette use, suggesting a progression toward more frequent use of both products over time. The shared risk factors examined here did not affect escalations in e-cigarette or cigarette use over time within individuals, but likely influence which youths use these products. Findings add to a growing body of evidence suggesting that e-cigarette use increases subsequent cigarette use in young people.

Does the gateway theory justify a ban on nicotine vaping in Australia?

Australia bans the sale, possession and use of liquid nicotine for vaping. One of the major arguments used to justify Australia's policy is that the availability of nicotine vaping products will lead a substantial number of young people who would otherwise not have smoked cigarettes to take up regular smoking (the gateway theory). In this article, we provide a critical analysis of the use of the gateway theory to justify Australian policy. We argue first that the evidence that vaping serves as a gateway to smoking is unconvincing. Smoking more often precedes vaping than vice versa, regular vaping by never-smokers is rare and the association is more plausibly explained by a common liability model. Second, we argue that even if the evidence were stronger it would not justify a ban on the sale of nicotine to adult smokers because there are other ways of preventing adolescent vaping that do not require a ban. We describe an alternative regulatory model for Australia that would address legitimate concerns about preventing adolescent uptake while allowing adult smokers to access these products for cessation or as an alternative to smoking cigarettes.

Does e-cigarette experimentation increase the transition to daily smoking among young ever-smokers in France?

INTRODUCTION

According to multiple studies, e-cigarette use among adolescents is associated with subsequent smoking initiation. However, little is known about its effect on the transition from smoking initiation to daily smoking.

METHODS

Using retrospective data from a French national representative survey collected in 2017 (n = 39,115), we analyzed the role of ever using e-cigarettes on daily cigarette smoking status at 17 among ever smokers (n = 21,401). Risk-ratios (RR) were computed through modified Poisson regressions with an inverse probability of treatment weighting (IPTW) approach.

RESULTS

Among French adolescents aged 17, 16.8 % declared current e-cigarette use (1.9 % reported daily use) and 34.1 % cigarette smoking (25.1 % reported daily smoking). Among ever-smokers, adolescents who declared having ever used e-cigarettes were less likely than those who did not to transition to daily smoking at 17: RR = 0.62 95 %CI [0.60 - 0.64]. We found similar results for those who experimented with e-cigarettes before initiating smoking, RR = 0.76 95 %CI [0.66 - 0.89].

CONCLUSIONS

Our results found no evidence of an increased risk of transitioning to daily smoking at 17 among ever-smokers who also experimented with e-cigarettes. Further studies should investigate the longer-term role of vaping on future smoking habits with the use of causal inference methods.

Longitudinal Tobacco Use Transitions Among Adolescents and Young Adults: 2014-2016

INTRODUCTION

Among youth, the frequency and prevalence of using more than one tobacco (small cigar, cigarette, and hookah) or nicotine-containing product (e-cigarettes-ENDS) are changing. These shifts pose challenges for regulation, intervention, and prevention campaigns because of scant longitudinal data on the stability of use patterns in this changing product landscape.

METHODS

A nationally representative longitudinal survey of 15- to 21-year olds (n = 15,275) was used to describe transitions between never use, noncurrent use, and past 30-day use of combustible tobacco, e-cigarettes (ENDS), and dual use of both kinds of products. A multistate model was fit to observations collected every 6 months across 2.5 years to estimate the probability of transitions between states (TPs), the average time in state (sojourn time), and the effect of age on transitions.

RESULTS

Current state strongly predicted future state over time intervals of 1 year or less, but only weakly predicted future state at longer intervals: TP to noncurrent use was higher for ENDS-only than combustible-only users over a 6-month interval but was similar for both groups over a 2-year interval. Sojourn time was significantly longer for combustible-only (0.52 years) and dual use (0.55 years) than ENDS-only use (0.27 years); older youth were more likely than younger youth to stay combustible tobacco users or noncurrent users.

CONCLUSIONS

The dynamics of transitions between combustible tobacco products and ENDS in a population of youth and young adults suggest that policy and prevention efforts must consider the frequent changes and instability over a 1-year or less time period in use patterns among young people.

IMPLICATIONS

The study addresses an urgent need in public health for timely information on how youth and young adults use tobacco and nicotine products. We found that youth, particularly adolescents, moved frequently between using ENDS and combustible tobacco products either alone or together. Importantly, the utility of current-use states for predicting future use states declined for time horizons longer than 1 year. Our results demonstrate a need for caution in interpreting product transitions. Longitudinal data with frequent observations and coverage of a wide range of possible product types is required to fully characterize usage patterns in youth.

E-cigarette use and onset of first cigarette smoking among adolescents: An empirical test of the 'common liability' theory

Background: E-cigarettes have become the most commonly used tobacco products among youth in the United States (US) recently. It is not clear whether there is a causal relationship between e-cigarette use and the onset of cigarette smoking. The "common liability" theory postulates that the association between e-cigarette use and cigarette smoking can be attributed to a common risk construct of using tobacco products. This study aims to investigate the relationship between ever e-cigarette use and cigarette smoking onset in the US using a structural equation modeling approach guided by the "common liability" theory. Methods: The study population is non-institutionalized civilian adolescents living in the US, sampled in the longitudinal Population Assessment of Tobacco and Health study. Information about tobacco product use was obtained via confidential self-report. A structural equation modeling approach was used to estimate the relationship between e-cigarette use at wave 1 and the onset of cigarette smoking at wave 2 after controlling for a latent construct representing a "common liability to use tobacco products." Results:  After controlling for a latent construct representing a "common liability to use tobacco products", ever e-cigarette use does not predict the onset of cigarette smoking (β=0.13, 95% CI= -0.07, 0.32, p=0.204). The latent "common liability to use tobacco products" is a robust predictor for the onset of cigarette smoking (β=0.38; 95% CI=0.07, 0.69; p=0.015). Conclusions: Findings from this study provide supportive evidence for the 'common liability' underlying observed associations between e-cigarette use and smoking onset.

E-cigarette use and onset of first cigarette smoking among adolescents: An empirical test of the 'common liability' theory

Background: E-cigarettes have become the most commonly used tobacco products among youth in the United States (US) recently. It is not clear whether there is a causal relationship between e-cigarette use and the onset of cigarette smoking. The "common liability" theory postulates that the association between e-cigarette use and cigarette smoking can be attributed to a common risk construct of using tobacco products. This study aims to investigate the relationship between ever e-cigarette use and cigarette smoking onset in the US using a structural equation modeling approach guided by the "common liability" theory. Methods: The study population is non-institutionalized civilian adolescents living in the US, sampled in the longitudinal Population Assessment of Tobacco and Health study. Information about tobacco product use was obtained via confidential self-report. A structural equation modeling approach was used to estimate the relationship between e-cigarette use at wave 1 and the onset of cigarette smoking at wave 2 after controlling for a latent construct representing a "common liability to use tobacco products." Results:  After controlling for a latent construct representing a "common liability to use tobacco products", ever e-cigarette use does not predict the onset of cigarette smoking (β=0.13, 95% CI= -0.07, 0.32, p=0.204). The latent "common liability to use tobacco products" is a robust predictor for the onset of cigarette smoking (β=0.38; 95% CI=0.07, 0.69; p=0.015). Conclusions: Findings from this study provide supportive evidence for the 'common liability' underlying observed associations between e-cigarette use and smoking onset.

E-cigarette use and onset of first cigarette smoking among adolescents: An empirical test of the 'common liability' theory

Background: E-cigarettes have become the most commonly used tobacco products among youth in the United States (US) recently. It is not clear whether there is a causal relationship between e-cigarette use and the onset of cigarette smoking. The "common liability" theory postulates that the association between e-cigarette use and cigarette smoking can be attributed to a common risk construct of using tobacco products. This study aims to investigate the relationship between ever e-cigarette use and cigarette smoking onset in the US using a structural equation modeling approach guided by the "common liability" theory. Methods: The study population is non-institutionalized civilian adolescents living in the US, sampled in the longitudinal Population Assessment of Tobacco and Health study. Information about tobacco product use was obtained via confidential self-report. A structural equation modeling approach was used to estimate the relationship between e-cigarette use at wave 1 and the onset of cigarette smoking at wave 2 after controlling for a latent construct representing a "common liability to use tobacco products." Results:  After controlling for a latent construct representing a "common liability to use tobacco products", ever e-cigarette use does not predict the onset of cigarette smoking (β=0.10, 95% CI= -0.09, 0.29, p=0.299). The latent "common liability to use tobacco products" is a robust predictor for the onset of cigarette smoking (β=0.42; 95% CI=0.08, 0.76; p=0.015). Conclusions: Findings from this study provide supportive evidence for the 'common liability' underlying observed associations between e-cigarette use and smoking onset.

Social norms towards smoking and vaping and associations with product use among youth in England, Canada, and the US

BACKGROUND

This study assesses differences in social norms towards smoking and vaping among youth across countries (England, Canada, US) and smoking and vaping status.

METHODS

Data are from the 2017 ITC Youth Tobacco and Vaping Survey, among youth age 16-19 in England (N = 3444), Canada (N = 3327), and US (N = 3509). Prevalence of friend smoking, friend vaping, peer approval of smoking, and peer approval of vaping were estimated. Adjusted logistic regression models were estimated for each norm to assess associations with country, smoking status, and vaping status, adjusting for sociodemographics, alcohol use, and marijuana use.

RESULTS

47% and 52% reported friend smoking and vaping respectively. Perceived peer approval of vaping (44%) was almost double that of smoking (23%). Compared with England, fewer Canadian and US youth reported friend smoking (Canada: AOR = 0.71 [95% CI = 0.62-0.82]; US: AOR = 0.54 [0.47-0.62]) and peer approval of smoking (Canada: AOR = 0.74 [0.63-0.87]; US: AOR = 0.78 [0.67-0.91]), yet more reported peer approval of vaping (Canada: AOR = 1.23 [1.08-1.41]; US: AOR = 1.30 [1.14-1.48]). More Canadian than English youth reported friend vaping (AOR = 1.17 [1.02-1.36]). Friend smoking, peer approval of smoking, and friend vaping were more common among smokers and vapers (all p < .02). Peer approval of vaping was more common among vapers but less common among smokers (all p < .044).

CONCLUSIONS

Youth had more positive vaping than smoking norms. English youth reported the most pro-smoking but least pro-vaping norms in adjusted models; this was unexpected given country differences in regulatory environments. Norms towards both products were associated with use, with some evidence of cross-product associations between norms and behaviours.

How to Think-Not Feel-about Tobacco Harm Reduction

INTRODUCTION

The debate over tobacco harm reduction (THR) has divided the tobacco control community into two camps, one expressing serious reservations about THR whereas the other believes that reduced-risk products like e-cigarettes will disrupt the cigarette market. The often emotional debate would benefit from dispassionate data-based evaluation of evidence.

METHODS

After briefly discussing harm reduction in public health and specifically in tobacco control, this paper identifies major issues concerning e-cigarettes and reviews relevant evidence. Issues include: e-cigarettes' risks compared to cigarette smoking; the effect of vaping on youth smoking; vaping's impact on adult smoking cessation; the net long-term public health implications of vaping; and differences in views on policy issues. The intent is to provide a broad overview of issues and evidence, directing readers to more detailed reviews of specific issues.

FINDINGS

Principal findings include the following: (1) while longitudinal studies suggest that vaping increases never-smoking young people's odds of trying smoking, national survey data indicate that adolescents' 30-day smoking prevalence decreased at an unprecedented rate precisely whereas vaping increased. Use of all other tobacco products also declined. (2) Recent population-level studies add evidence that vaping is increasing adult smoking cessation. (3) Vaping is likely to make a positive contribution to public health.

CONCLUSIONS

THR can be a complement to, not a substitute for, evidenced-based tobacco control interventions. Tobacco control professionals need to focus on objective assessment of and discussion about the potential costs and benefits of THR.

IMPLICATIONS

Participants on both sides of the divisive THR debate need to examine the complicated issues and evidence more objectively. This entails considering both the potential benefits and costs associated with reduced-risk products like e-cigarettes. Furthermore, it requires examining different kinds of evidence when considering specific issues. For example, those concerned by longitudinal study findings that vaping increases students' trial of cigarettes should consider US national survey evidence that youth smoking has decreased at an unprecedented rate. A review of the major issues suggests that the potential of vaping to assist adult smokers to quit outweighs the potential negatives.

Vaping Expectancies: A Qualitative Study among Young Adult Nonusers, Smokers, Vapers, and Dual Users

BACKGROUND

"Expectancies," or beliefs about outcomes, robustly correlate with and predict several behaviors including electronic nicotine delivery system ("e-cigarette") use. However, there is limited qualitative research available regarding relevant e-cigarette vaping expectancies.

OBJECTIVES

The present study used a qualitative approach to derive and refine e-cigarette expectancy themes among young adults.

METHODS

We conducted 12 focus groups and two individual interviews with young adult nonusers, e-cigarette vapers, cigarette smokers, and dual users to assess beliefs about the effects of e-cigarettes. After a series of open-ended questions, follow-up questions assessed reactions to domains previously examined in expectancy measures for cigarette smoking and e-cigarette vaping. The constant comparative method was used to derive themes from transcripts.

RESULTS

Four main themes (Positive Reinforcement, Social Benefits, Negative Affect Reduction, Negative Consequences) emerged from the results. Each theme contained three associated subthemes (Positive Reinforcement: Sensorimotor Experiences, Taste, Stimulation; Social Benefits: Social Facilitation, Influence on Others, Convenience; Negative Affect Reduction: Stress Reduction, Appetite Reduction, Boredom Reduction; and Negative Consequences: Health Risks, Addiction, Secondhand Effects).

CONCLUSIONS/IMPORTANCE

Previously identified smoking expectancies appear relevant for young adult vaping, with some notable refinements. Positive reinforcement aspects encompassed aerosol clouds, vaping tricks, and unique flavors. Social benefits included influencing others via social media and competitive activity, as well as the convenience of use in a variety of places. Negative affect reduction was controversial among user groups, but vaping was seen as more interesting than smoking and thus more effective at boredom reduction. Young adults were uncertain regarding negative consequences, but appreciated a potential for secondhand effects. Measure refinement via qualitative research and future field testing can enhance our understanding of this relatively new behavior, supporting tobacco control surveillance, marketing/labeling regulations, and counter-advertising development/evaluation.

The moderating effect of gender on the association between E-cigarette use and smoking status: A cross-sectional study

INTRODUCTION

The novel features of e-cigarettes in the recent vaping boom are appealing to females. Given increasing concerns about using e-cigarettes among females, understanding the patterns of using e-cigarettes in females compared to males is critical. We investigate the moderating effect of gender on the association between ever vaping and smoking status and gender differences in reason for ever vaping and in having ever stopped smoking.

METHODS

We used population data (n = 38,661) from the 2015, 2016, and 2017 Texas Behavioral Risk Factor Surveillance System (BRFSS) to examine a gender difference in ever vaping associated with smoking status. Additionally, we restricted the sample to current smokers who have ever vaped (n = 4733) to examine the association of gender with quitting smoking as reason for ever vaping and with having ever stopped smoking.

RESULTS

We found a significant association between ever vaping and gender (OR = 0.77, 95%CI = 0.65, 0.91). When smoking status was considered, female never-smokers had a significantly lower likelihood of ever vaping than male never-smokers (OR = 0.43, 95%CI = 0.27, 0.76). No significant gender difference was found in ever vaping to quit smoking (OR = 1.12, 95%CI = 0.73, 1.74) and having ever stopped smoking (OR = 1.41, 95%CI = 0.95, 2.10).

CONCLUSIONS

The findings of this study provide evidence of gender differences in vaping patterns. Female never-smokers are less likely than male never-smokers to experiment with e-cigarettes. However, there is no evidence of a gender difference in both ever vaping to quit smoking and having ever stopped smoking. Consistent monitoring of gender differences in using e-cigarettes and stratified policy approaches tailored for genders are necessary.

The E-Cigarette Debate: What Counts as Evidence?

Two major public health evaluations of e-cigarettes-one from the National Academies of Science, Engineering, and Medicine (NASEM), the other from Public Health England (PHE)-were issued back to back in the winter of 2018. While some have read these analyses as broadly consistent, providing support for the view that e-cigarettes could play a role in smoking harm reduction, in every major respect, they come to very different conclusions about what the evidence suggests in terms of public health policy. How is that possible? The explanation rests in what the 2 reports see as the central challenge posed by e-cigarettes, which helped to determine what counted as evidence. For NASEM, the core question was how to protect nonsmokers from the potential risks of exposure to nicotine and other contaminants or from the risk of smoking combustible cigarettes through renormalization. A precautionary standard was imperative, making evidence that could speak most conclusively to the question of causality paramount. For PHE, the priority was how to reduce the burdens now borne by current smokers, burdens reflected in measurable patterns of morbidity and mortality. With a focus on immediate harms, PHE turned to evidence that was "relevant and meaningful." Thus, competing priorities determined what counted as evidence when it came to the impact of e-cigarettes on current smokers, nonsmoking bystanders, and children and adolescents. A new clinical trial demonstrating the efficacy of e-cigarettes as a cessation tool makes understanding how values and framing shape core questions and conclusive evidence imperative.

Young people's perspectives of e-cigarette use in the home

There is concern that the emergence of e-cigarettes could result in an increase in young people's intake of, and exposure to, nicotine. This UK study used friendship group interviews to elicit the perspectives of young people from socioeconomically contrasting backgrounds regarding e-cigarettes. Young people from both advantaged and disadvantaged backgrounds described similar e-cigarette practices in the home environment, and, for both health and sensory reasons, viewed these as preferable to tobacco smoking. Space-related practices of adult e-cigarette use in the home were revealed to be more malleable than those of tobacco use. Results also highlighted that e-cigarettes offered young people new opportunities for nicotine consumption in the home. Methods of storing e-cigarettes in domestic spaces posed safety risks to younger children and easy access to e-cigarettes for others.

Ecological momentary assessment of various tobacco product use among young adults

INTRODUCTION

Young adults are at high risk for using traditional and novel tobacco products. However, little is known about daily/weekly use patterns or psychosocial triggers for using various tobacco products.

METHODS

This ecological momentary assessment (EMA) study examined timing, tobacco cravings, affect, social context, and other substance use (alcohol, marijuana) in relation to use of cigarettes, electronic nicotine delivery systems (ENDS), and any tobacco product (i.e., cigarettes, ENDS, cigars, hookah), respectively. We also examined interactions between these predictors, sex, and race/ethnicity. From a longitudinal study of 3418 18-25 year-olds from seven Georgia colleges/universities, we recruited 72 reporting current tobacco use to participate in the 21-day EMA study; 43 participated, of which 31 completed ≥66% assessments and were analyzed. Cravings, affect, social context, and substance use were assessed daily across four four-hour windows.

RESULTS

Of the 31 participants, average age was 21.10 years (SD = 1.95), 45.2% were female, and 71.0% non-Hispanic White; 71.0% used cigarettes, 58.1% ENDS, 38.7% cigars, and 25.8% hookah (25.6% used one product, 46.5% two, 27.9% ≥ three). Predictors of cigarette use included higher anxiety, greater odds of marijuana and alcohol use, and higher boredom levels among women. Predictors of ENDS use included being non-White and greater odds of marijuana use, as well as higher tobacco cravings among women and higher boredom among men. Predictors of any tobacco product use included being non-White, higher boredom levels, and greater odds of marijuana and alcohol use.

CONCLUSIONS

Distinct interventions may be needed to address use of differing tobacco products among young adults.

Associations of risk factors of e-cigarette and cigarette use and susceptibility to use among baseline PATH study youth participants (2013-2014)

INTRODUCTION

Improved understanding of the distribution of traditional risk factors of cigarette smoking among youth who have ever used or are susceptible to e-cigarettes and cigarettes will inform future longitudinal studies examining transitions in use.

METHODS

Multiple logistic regression analysis was conducted using data from youth (ages 12-17 years) who had ever heard of e-cigarettes at baseline of the PATH Study (n = 12,460) to compare the distribution of risk factors for cigarette smoking among seven mutually exclusive groups based on ever cigarette/e-cigarette use and susceptibility status.

RESULTS

Compared to committed never users, youth susceptible to e-cigarettes, cigarettes, or both had increasing odds of risk factors for cigarette smoking, with those susceptible to both products at highest risk, followed by cigarettes and e-cigarettes. Compared to e-cigarette only users, dual users had higher odds of nearly all risk factors (aOR range = 1.6-6.8) and cigarette only smokers had higher odds of other (non-e-cigarette) tobacco use (aOR range = 1.5-2.3), marijuana use (aOR = 1.9, 95%CI = 1.4-2.5), a high GAIN substance use score (aOR = 1.9, 95%CI = 1.1-3.4), low academic achievement (aOR range = 1.6-3.4), and exposure to smoking (aOR range = 1.8-2.1). No differences were observed for externalizing factors (depression, anxiety, etc.), sensation seeking, or household use of non-cigarette tobacco.

CONCLUSIONS

Among ever cigarette and e-cigarette users, dual users had higher odds of reporting traditional risk factors for smoking, followed by single product cigarette smokers and e-cigarette users. Understanding how e-cigarette and cigarette users differ may inform youth tobacco use prevention efforts and advise future studies assessing probability of progression of cigarette and e-cigarette use.

Preventing Smoking Progression in Young Adults: the Concept of Prevescalation

As adolescents cross the threshold to young adulthood, they encounter more opportunities to engage in or accelerate previously discouraged or prohibited behaviors. Young adults, therefore, are more apt to initiate cigarette smoking and, more importantly, to accelerate their use if they tried and experimented as an adolescent. Preventing the escalation and entrenchment of smoking in the young adult years is critically important to reducing tobacco's long-term health toll. However, traditional interventions for youth have focused on preventing smoking initiation, and interventions for adults have focused on smoking cessation; both have failed to address the needs of young adults. We introduce the concept of "prevescalation" to capture the need and opportunity to prevent the escalation of risk behaviors that typically occur during young adulthood, with a focus on the example of cigarette smoking. Prevescalation negates the notion that prevention has failed if tobacco experimentation occurs during adolescence and focuses on understanding and interrupting transitions between experimentation with tobacco products and established tobacco use that largely occur during young adulthood. However, since risk behaviors often co-occur in young people, the core concept of prevescalation may apply to other behaviors that co-occur and become harder to change in later adulthood. We present a new framework for conceptualizing, developing, and evaluating interventions that better fit the unique behavioral, psychosocial, and socio-environmental characteristics of the young adult years. We discuss the need to target this transitional phase, what we know about behavioral pathways and predictors of cigarette smoking, potential intervention considerations, and research challenges.

Electronic Cigarette Use and Smoking Initiation in Taiwan: Evidence from the First Prospective Study in Asia

A growing literature indicates that electronic cigarette use increases the risk of subsequent initiation of conventional smoking among cigarette-naïve adolescents in several Western countries. This research assesses the same relationship in an Asian country, Taiwan. The Taiwan Adolescent to Adult Longitudinal Study is a school-based survey that was carried out in two waves in 2014 (baseline) and in 2016 (follow-up). It employs probability sampling to create nationally representative samples of students in junior high school (mean age 13, 7th grade at baseline) and in senior high school (mean age 16, 10th grade at baseline). Data from this survey were analyzed via logistic regression to estimate the association between ever use of e-cigarettes at baseline and smoking initiation at follow-up, accounting for susceptibility to smoking, socio-demographic profile, depression status, and peer support. Among the 12,954 cigarette-naïve students surveyed, those with e-cigarette experience at baseline exhibited higher odds of smoking initiation at follow-up (Odds Ratio = 2.14, 95% CI (1.66, 2.75), p < 0.001). For the first time, we confirmed, through a longitudinal survey, a prospective association between ever use of e-cigarettes and smoking initiation in an Asian adolescent population. The restrictive policy on e-cigarettes currently in force in Taiwan is justified to prevent both e-cigarette and cigarette use among adolescents.

Association of Electronic Cigarette Use With Subsequent Initiation of Tobacco Cigarettes in US Youths

IMPORTANCE

The use of electronic cigarettes (e-cigarettes) and other noncigarette tobacco products may increase the odds of cigarette initiation, even among low-risk youths.

OBJECTIVE

To evaluate the associations of prior e-cigarette use and other tobacco product use with subsequent cigarette initiation within 2 years of follow-up.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective cohort study, data from waves 1 through 3 of the Population Assessment of Tobacco and Health Study (2013-2016) were used to assess youths aged 12 to 15 years who had never used cigarettes, e-cigarettes, or other tobacco products at wave 1. This was a nationally representative study of the US population. Data analysis was conducted in 2018.

EXPOSURES

First noncigarette tobacco product used (none, e-cigarette, or other tobacco product) between wave 1 and wave 3.

MAIN OUTCOMES AND MEASURES

Ever cigarette use and current cigarette use at wave 3.

RESULTS

In the sample (N = 6123), respondents were 49.5% female; 54.1% non-Hispanic, white; and the mean (SD) age was 13.4 (1.2) years. Of these, 8.6% reported e-cigarettes as their first tobacco product, while 5.0% reported using another noncigarette product first; 3.3% reported using cigarettes first. Cigarette use at wave 3 was higher among prior e-cigarette users (20.5%) compared with youths with no prior tobacco use (3.8%). Prior e-cigarette use was associated with more than 4 times the odds of ever cigarette use (odds ratio, 4.09; 95% CI, 2.97-5.63) and nearly 3 times the odds of current cigarette use (odds ratio, 2.75; 95% CI, 1.60-4.73) compared with no prior tobacco use. Prior use of other tobacco products was similarly associated with subsequent ever cigarette use (OR, 3.84; 95% CI, 2.63-5.63) and current cigarette use (OR, 3.43; 95% CI, 1.88-6.26) compared with no prior tobacco use. The association of prior e-cigarette use with cigarette initiation was stronger among low-risk youths (OR, 8.57; 95% CI, 3.87-18.97), a pattern not seen for prior other product use. Over the 2 years between 2013 and 2014 and 2015 and 2016, 21.8% of new cigarette ever use (178 850 youths) and 15.3% of current cigarette use (43 446 youths) among US youths aged 12 to 15 years may be attributable to prior e-cigarette use.

CONCLUSIONS AND RELEVANCE

This study's findings support the notion that e-cigarette use is associated with increased risk for cigarette initiation and use, particularly among low-risk youths. At the population level, the use of e-cigarettes may be a contributor to the initiation of cigarette smoking among youths.

E-cigarette use in England 2014-17 as a function of socio-economic profile

BACKGROUND AND AIMS

E-cigarettes have the potential either to decrease or increase health inequalities, depending on socio-economic differences in their use and effectiveness. This paper estimated the associations between socio-economic status (SES) and e-cigarette use and examined whether these associations changed between 2014 and 2017.

DESIGN

A monthly repeat cross-sectional household survey of adults (16+) between January 2014 and December 2017. This time-period was chosen given that the prevalence of e-cigarette use stabilized in England in late 2013.

SETTING

England.

PARTICIPANTS

Participants in the Smoking Toolkit Study, a monthly household survey of smoking and smoking cessation among adults (n = 81 063; mean age = 48.4 years, 49% were women) in England. Subsets included past year smokers (n = 16 232; mean age = 42.8, 46% women), smokers during a quit attempt (n = 5305, mean age = 40.6, 49% women) and long-term ex-smokers (n = 13 562, mean age = 59.3, 44% women).

MEASUREMENTS

The outcome measure for the analyses was current e-cigarette use. We also included smokers during a quit attempt where use of an e-cigarette during the most recent quit attempt was the outcome measure. Social grade based on occupation was the SES explanatory variable, using the National Readership Survey classification system of AB (higher and intermediate managerial, administrative and professional), C1 (supervisory, clerical and junior managerial, administrative and professional), C2 (skilled manual workers), D (semi-skilled and unskilled manual workers) and E (state pensioners, casual and lowest-grade workers, unemployed with state benefits only). The analyses were stratified by year to assess the changes in these associations over time.

FINDINGS

Among past-year smokers, lower SES groups had lower overall odds of e-cigarette use compared with the highest SES group AB (D: odds ratio = 0.53, 95% confidence interval = 0.40-0.71; E: 0.67, 0.50-0.89). These differences in e-cigarette use reduced over time. The use of e-cigarettes during a quit attempt showed no clear temporal or socio-economic patterns. Among long-term ex-smokers, use of e-cigarettes increased from 2014 to 2017 among all groups and use was more likely in SES groups C2 (2.03, 1.08-3.96) and D (2.29, 1.13-4.70) compared with AB.

CONCLUSIONS

From 2014 to 2017 in England, e-cigarette use was greater among smokers from higher compared with lower socio-economic status (SES) groups, but this difference attenuated over time. Use during a quit attempt was similar throughout SES groups. Use by long-term ex-smokers increased over time among all groups and was consistently more common in lower SES groups.