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

New Estimates of Smoking-Attributable Mortality in the U.S. From 2020 Through 2035

INTRODUCTION

The often-cited Centers for Disease Control and Prevention (CDC) estimate of 480,000 annual U.S. smoking-attributable deaths (SADs), including 439,000 first-hand smoke deaths, derives from 2005 to 2009 data. Since then, adult smoking prevalence has decreased by 40%, while the population has grown and the smoking population aged. An updated estimate is presented to determine whether the CDC figure remains accurate or has changed substantially. In addition, the likely annual smoking-related mortality toll is projected through 2035.

METHODS

A well-established model of smoking prevalence and health effects is employed to estimate annual SADs among individuals exposed to first-hand smoke in the U.S. for two distinct periods: 2005-2009 and 2020-2035. The estimate for 2005-2009 serves as a benchmark to evaluate the reliability of the model's estimate in comparison to CDC's. The projections for 2020-2035 provide up-to-date figures for SADs, predicting how annual SADs are likely to change in the coming years. Data were collected between 2005 and 2020. The analysis was conducted in 2023.

RESULTS

This study's estimate of 420,000 first-hand smoke deaths over 2005-2009 is 95.7% of CDC's estimate during the same period. The model projections indicate that SADs among individuals who currently smoke or formerly smoked have increased modestly since 2005-2009. Beginning in 2020, annual SADs will remain relatively stable at approximately 450,000 before starting to decline around 2030.

CONCLUSIONS

These findings suggest that the CDC estimate of the annual mortality burden of smoking remains valid. Despite U.S. population growth and the aging of the smoking population, substantial reductions in smoking will finally produce a steady, if gradual, decline in SADs beginning around 2030.

Perceived relative harm of e-cigarettes among Ukrainian adults

OBJECTIVES

Emerging evidence suggests that the use of safer nicotine products (SNPs), such as e-cigarettes and heated tobacco products (HTPs) poses significantly lower health risks than continued smoking, particularly over the short and medium term. However, it remains uncertain whether the public has been adequately informed about these relative risks. This study assesses the perceived relative harm of e-cigarettes compared to conventional cigarettes in Ukraine.

METHODS

Two nationally representative surveys were conducted in February 2021 and December 2022. Participants, irrespective of their smoking status, were asked whether they agreed with the statement that "using e-cigarettes is more harmful than smoking conventional cigarettes". The surveys also included questions about tobacco product usage, the most dangerous substances in cigarettes, and smoking cessation methods. The data were statistically analysed by deriving design-based weighted point estimates and 95% confidence intervals for the proportions within each response category.

RESULTS

In 2022, 38.1% (95% CI: 35.3-40.9) of adults believed that e-cigarettes were more harmful than cigarettes and the perception of relative harm remained relatively unchanged between the two surveys. Furthermore, 56.2% (95% CI: 50.0-62.2) of current cigarette smokers agreed with this statement, while only a small percentage of vapers (e-cigarette users) 7.4% (95% CI: 1.5-30.0) perceived e-cigarettes as more harmful than conventional cigarettes. Among non-smokers and dual users the share was 33.4% (95% CI: 30.0-36.9) and 32.7% (95% CI: 25.1-41.5), respectively.

CONCLUSION

Our findings indicate that in Ukraine the perception that e-cigarettes are more harmful than cigarettes, or the lack of knowledge regarding relative risks, prevails. This highlights the importance of accurate risk communication to promote a harm reduction approach to tobacco use.

Comparison of smoking prevalence in Canada before and after nicotine vaping product access using the SimSmoke model

OBJECTIVES

The public health impact of nicotine vaping products (NVPs) is subject to complex transitions between NVP and cigarette use. To circumvent the data limitations and parameter instability challenges in modeling transitions, we indirectly estimate NVPs' impact on smoking prevalence and resulting smoking-attributable deaths using the SimSmoke simulation model.

METHODS

Canada SimSmoke uses age- and sex-specific data on Canadian population, smoking prevalence and tobacco control policies. The model incorporates the impact of cigarette-oriented policies on smoking prevalence but not the explicit contribution of NVPs. The model was calibrated from 1999 to 2012, thereby projecting smoking prevalence before NVPs were widely used in Canada. The NVP impact on smoking prevalence is inferred by comparing projected 2012-2020 smoking trends absent NVPs to corresponding trends from two Canadian national surveys. We further distinguish impacts before and after NVPs became regulated in 2018 and more available.

RESULTS

Comparing 2012-2020 survey data of post-NVP to SimSmoke projected smoking prevalence trends, one survey indicated an NVP-related relative reduction of 15% (15%) for males (females) age 15+, but 32% (52%) for those ages 15-24. The other survey indicated a 14% (19%) NVP-related smoking reduction for ages 18+, but 42% (53%) for persons ages 18-24. Much of the gain occurred since Canada relaxed NVP restrictions. NVP-related 2012-2020 smoking reductions yielded 100,000 smoking-attributable deaths averted from 2012 to 2060.

CONCLUSION

Smoking prevalence in Canada, especially among younger adults, declined more rapidly once NVPs became readily available. The emergence of NVPs into the Canadian marketplace has not slowed the decline in smoking.

Abuse liability of two electronic nicotine delivery systems compared with combustible cigarettes and nicotine gum from an open-label randomized crossover study

An assessment of the likelihood of use and abuse potential for new tobacco products is an important part of tobacco product regulation in the United States and abroad. This paper reports the results of a randomized, open-label, crossover clinical study that assessed factors related to product adoption and abuse liability (AL), comparing two closed electronic nicotine delivery system (ENDS) products to combustible cigarettes and nicotine gum, high- and low-AL comparator products, respectively. During an 11-day confinement period that included multiple product familiarization sessions, healthy adult smokers participated in AL test sessions to evaluate the abuse liability of each product. During these test sessions, changes in subjective measures; speed and amount of nicotine uptake; and maximum changes in physiological effects before, during, and after use of each assigned product were assessed over 4 h. Positive subjective effects measures scores such as product-liking and overall intent to use again were highest for cigarettes, followed by the Vuse ENDS, with nicotine gum consistently having the lowest scores. The PK results (Cmax and Tmax) of the Vuse ENDS products are between UB cigarettes and nicotine gum, which correlates with the subjective effects. All nicotine uptake measures for the Vuse ENDS products were lower than that of usual brand (UB) cigarettes, including peak nicotine uptake and overall nicotine uptake, and were either similar to or lower than nicotine gum. The time course of nicotine uptake after use of the ENDS was more similar to that of combustible cigarettes than nicotine gum. The results indicate that the AL of each ENDS product is lower than that of UB cigarettes and similar to that of nicotine gum.

Examination of the impact of myblu electronic nicotine delivery system e-liquid nicotine strength on self-reported measures of dependence

BACKGROUND

Greater nicotine delivery is associated with higher nicotine concentrations in electronic nicotine delivery system (ENDS) liquids. However, there is a current debate as to whether this leads to increased dependence and mitigates ENDS public health potential.

METHODS

Self-reported dependence among users of myblu ENDS containing different nicotine concentrations was examined with data from a multiwave cross-sectional survey of US young adults and adults. Questions examined responses related to dependence measures and participants' most often used myblu ENDS nicotine concentration (low: 0%, 1% and 1.2%; medium: 2%, 2.4% and 2.5%; or high: 3.6% and 4%).

RESULTS

A global general linear model using nicotine concentration, age and days myblu that was used in the past 30 revealed a significant difference in PROMIS scores among nicotine concentration groups (F = 4.07, p = 0.02). However, pairwise comparisons to examine which specific groups differed significantly from others showed no significant differences. Logistic regression demonstrated that strong past 30-day cravings to use myblu among participants using high or medium nicotine concentrations were not significantly different from those using a low concentration (ORs 0.66 [0.42, 1.03], p = 0.07 and 0.95 [0.49, 1.82], p = 0.98, respectively). Time to daily first use for high or medium nicotine concentration users was not significantly different from those using a low concentration (ORs 0.89 [0.70, 1.14], p = 0.35 and 0.84 [0.57, 1.25], p = 0.40, respectively).

CONCLUSIONS

Use of myblu ENDS with different nicotine concentrations is not associated with differing levels of dependence. Our findings contradict the notion that high ENDS e-liquid nicotine levels generate increased dependence.

Curiosity and intentions to use myblu e-cigarettes and an examination of the 'gateway' theory: Data from cross-sectional nationally representative surveys

Encouraging adult smokers who are uninterested or unwilling to quit, and would otherwise continue to smoke, to transition to potentially less harmful nicotine products such as electronic nicotine delivery systems (ENDS) may positively impact population health. However, counterbalancing this benefit is the societal concern that ENDS may be used by never smokers and youth and serve as a 'gateway' into cigarette smoking. Data were analysed from two independent surveys of the prevalence and perceptions of myblu ENDS use in the United States. Total sample size was 22,232 young adults and 23,264 adults. Being curious to use myblu was 1.6-2.0 times more likely in young adult current smokers than young adult never smokers. This likelihood was 2.8 times greater for adult current smokers compared with adult never smokers in the perceptions survey, while in the prevalence survey, there was no difference between adult current and never smokers. Intentions to use myblu were significantly greater in young adult current smokers compared with young adult never smokers in both surveys and in adults in the prevalence survey. In all surveys and age cohorts, 124 of 45,496 participants (0.1% of the total survey population) reported first using myblu prior to smoking cigarettes and went on to become established smokers. Curiosity and intentions to use myblu were generally higher in current smokers compared with never smokers. There was minimal evidence to suggest the existence of a 'gateway' effect to established cigarette smoking among never-smoking myblu users.

Behavioral intentions assessment of a disposable e-cigarette among adult current, former, and non-smokers in the United States

Modeling the public health effects of e-cigarettes requires estimates of the likelihood that different individuals and population subgroups will start using e-cigarettes and subsequently transition to and from combustible cigarette use. To begin to generate input values for modeling efforts, this study assessed adults' behavioral intentions in relation to a disposable e-cigarette, "BIDI® Stick." An online questionnaire assessed intentions to try and use a BIDI® Stick regularly in 11 flavor variants among United States (U.S.) nationally representative samples of adult (21+ years) non-smokers (n = 2284), current smokers (n = 2391), former smokers (n = 2241), and young adult (21-24 years) non-smokers (n = 1140) of combustible cigarettes following exposure to product information and images. Current smokers rated their intentions to use a BIDI® Stick to partially or completely replace cigarettes. Positive intention to try a BIDI® Stick at least once was, for each flavor variant, highest among current smokers (22.4%-28.1%), lower among former smokers (6.0%-9.7%) and non-smokers (3.4%-5.2%), and lowest among never-smokers (1.0%-2.4%). Among current smokers, former smokers, and non-smokers, trial and regular use intentions were lowest among e-cigarette non-users and e-cigarette never-users. Approximately 23.6% of current smokers reported an intention to use a BIDI® Stick in at least one flavor to completely switch from cigarettes and/or to reduce cigarette consumption. Low trial and regular use intentions suggest that U.S. adults who do not currently smoke cigarettes and/or use e-cigarettes are unlikely to initiate use of the BIDI® Stick e-cigarette. Trial and regular use intentions are highest among adults who currently smoke cigarettes and/or use e-cigarettes. A moderate proportion of current smokers may try using a BIDI® Stick e-cigarette as a partial or complete replacement for combustible cigarettes.

Assessing the impact of protonating acid combinations in e-cigarette liquids: a randomised, crossover study on nicotine pharmacokinetics

The addition of protonating acids to e-cigarette liquid formulations (e-liquids) enhances nicotine bioavailability in e-cigarette use. However, little is known about the impact of different combinations of protonating acid on nicotine pharmacokinetics. The objectives of this study were to compare pharmacokinetics of nicotine absorption following use of a closed-system e-cigarette, containing e-liquids with two different nicotine levels and with different ratios of three common protonating acids-lactic, benzoic and levulinic. In a randomised, controlled, crossover study, nicotine pharmacokinetics and product liking were assessed for prototype e-liquids used in a Vuse e-cigarette containing either 3.5% or 5% nicotine and varying ratios of lactic, benzoic and/or levulinic acid. During an 8-day confinement period, 32 healthy adult current cigarette smokers/e-cigarette dual users used a single study e-liquid each day during 10-min fixed and ad libitum use periods after overnight nicotine abstinence. For most comparisons, Cmax and AUC0-60 following both fixed and ad libitum puffing were significantly higher for e-liquids containing 5% nicotine compared with 3.5% nicotine. However, Cmax and AUC0-60 were not statistically different for 5% nicotine e-liquids containing varying ratios of lactic, levulinic and benzoic acid when compared to an e-liquid containing lactic acid only. Mean scores for product liking were similar for all e-liquid formulations assessed, regardless of nicotine concentration, acid content, and whether the product was used in a fixed or ad libitum puffing regimen. While e-liquid nicotine concentration significantly affected users' nicotine uptake, the different combinations of benzoic, levulinic and lactic acid in the e-liquids assessed had limited impact on nicotine pharmacokinetics and product liking scores.

Predicting the long-term effects of electronic cigarette use on population health: a systematic review of modelling studies

OBJECTIVE

To systematically review and synthesise the findings of modelling studies on the population impacts of e-cigarette use and to identify potential gaps requiring future investigation.

DATA SOURCE AND STUDY SELECTION

Four databases were searched for modelling studies of e-cigarette use on population health published between 2010 and 2023. A total of 32 studies were included.

DATA EXTRACTION

Data on study characteristics, model attributes and estimates of population impacts including health outcomes and smoking prevalence were extracted from each article. The findings were synthesised narratively.

DATA SYNTHESIS

The introduction of e-cigarettes was predicted to lead to decreased smoking-related mortality, increased quality-adjusted life-years and reduced health system costs in 29 studies. Seventeen studies predicted a lower prevalence of cigarette smoking. Models that predicted negative population impacts assumed very high e-cigarette initiation rates among non-smokers and that e-cigarette use would discourage smoking cessation by a large margin. The majority of the studies were based on US population data and few studies included factors other than smoking status, such as jurisdictional tobacco control policies or social influence.

CONCLUSIONS

A population increase in e-cigarette use may result in lower smoking prevalence and reduced burden of disease in the long run, especially if their use can be restricted to assisting smoking cessation. Given the assumption-dependent nature of modelling outcomes, future modelling studies should consider incorporating different policy options in their projection exercises, using shorter time horizons and expanding their modelling to low-income and middle-income countries where smoking rates remain relatively high.

Impacts of EU Tobacco Products Directive regulations on use of e-cigarettes in adolescents in Great Britain: a natural experiment evaluation

Background

E-cigarettes are a popular smoking-cessation tool. Although less harmful than tobacco, use of e-cigarettes by non-smokers should be prevented. There is concern about the use of e-cigarettes by young people and that e-cigarettes may renormalise smoking. In May 2016, Tobacco Products Directive regulations aimed to reduce e-cigarettes' appeal to young people.

Aims

To examine the effects of the Tobacco Products Directive regulations on young people's use of e-cigarettes, and the role of e-cigarettes in renormalising smoking.

Design

A mixed-method natural experimental evaluation combining secondary analyses of survey data, with process evaluation, including interviews with young people, policy stakeholders, retailers and trading standards observers, and observations of retail settings.

Settings

Wales, Scotland and England.

Participants

Survey participants were aged 13-15 years, living in England, Scotland or Wales and participated in routinely conducted surveys from 1998 to 2019. Process evaluation participants included 14- to 15-year-olds in England, Scotland and Wales, policy stakeholders, trading standards offices and retailers.

Intervention

Regulation of e-cigarettes, including bans on cross-border advertising, health warnings and restrictions on product strength.

Comparison group

Interrupted time series design, with baseline trends as the comparator.

Main outcome measures

The primary outcome was ever e-cigarette use. Secondary outcomes included regular use, ever and regular smoking, smoking attitudes, alcohol and cannabis use.

Data capture and analysis

Our primary statistical analysis used data from Wales, including 91,687 young people from the 2013-19 Health Behaviour in School-aged Children and School Health Research Network surveys. In Scotland, we used the Scottish Schools Adolescent Lifestyle and Substance Use Survey and in England we used the Smoking Drinking and Drug Use surveys. The process evaluation included interviews with 73 young people in 2017 and 148 young people in 2018, 12 policy stakeholders, 13 trading standards officers and 27 retailers. We observed 30 retail premises before and after implementation. Data were integrated using the Medical Research Council's process evaluation framework.

Results

Ever smoking continued to decline alongside the emergence of e-cigarettes, with a slight slowing in decline for regular use. Tobacco Products Directive regulations were described by stakeholders as well implemented, and observations indicated good compliance. Young people described e-cigarettes as a fad and indicated limited interaction with the components of the Tobacco Products Directive regulations. In primary statistical analyses in Wales [i.e. short (to 2017) and long term (to 2019)], growth in ever use of e-cigarettes prior to Tobacco Products Directive regulations did not continue after implementation. Change in trend was significant in long-term analysis, although of similar magnitude at both time points (odds ratio 0.96). Data from England and Scotland exhibited a similar pattern. Smoking followed the opposite pattern, declining prior to the Tobacco Products Directive regulations, but plateauing as growth in e-cigarette use stalled.

Limitations

Alternative causal explanations for changes cannot be ruled out because of the observational design.

Conclusions

Young people's ever and regular use of e-cigarettes appears to have peaked around the time of the Tobacco Products Directive regulations and may be declining. Although caution is needed in causal attributions, findings are consistent with an effect of regulations. Our analysis provides little evidence that e-cigarettes renormalise smoking. More recent data indicate that declines in smoking are plateauing.

Future work

International comparative work to understand differences in use of e-cigarettes, and tobacco, within varying regulatory frameworks is a priority.

Study registration

This study is registered as ResearchRegistry4336.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 11, No. 5. See the NIHR Journals Library website for further project information.

The Potential Impact of E-cigarettes on the Life-Years Lost from Conventional Smoking in the Russian Federation

This study analyses the potential impact of e-cigarettes on the death toll of cigarette smoking in the Russian Federation by working under a variety of assumptions pertaining to how much vaping might affect smoking cessation and initiation, and its adverse impacts on health in comparison to conventional smoking. Within this study, each combination of these assumptions generates a single vaping scenario (210 in total). A dynamic population simulation model, specifically for the Russian Federation, that is tailoured to tobacco control policy analysis, is built for estimation purposes. Considering the toll of smoking on cumulative life-years saved via the inclusion of vaping across a period of 80 years, the simulation analysis produces positive results in 88.1% of e-cigarette scenarios, ranging from - 3.3 million to 38.5 million life-years saved. In relative terms, the estimated life-years saved from vaping varies from - 1.6 to 18.6% of the predicted life-years lost from smoking. Most of the model scenarios involve a significant number of individuals who stopped smoking in favour of vaping. These results suggest that vaping has great potential to reduce the prevalence of smoking and the related death toll in the Russian Federation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10603-023-09540-z.

The Role of Flavored Electronic Nicotine Delivery Systems in Smoking Cessation: A Systematic Review

Background

Electronic nicotine delivery systems (ENDS) come in numerous flavors and may aid smoking cessation. This systematic review examines evidence on the role of ENDS flavors in smoking cessation.

Methods

We searched EMBASE OVID, PsychInfo, and Medline databases for studies that: 1) examined cigarette cessation outcomes for persons using ENDS (intent, attempts, and success) and 2) reported results separated by respondent's ENDS flavor used. We extracted crude and adjusted odds ratios for associations between cessation outcomes and types of ENDS flavors used (nontobacco vs. tobacco/unflavored; nontobacco and nonmenthol vs. tobacco/unflavored and menthol). We did not consider cessation outcomes among people not using ENDS. We evaluated the evidence using the GRADE approach, focusing on consistency and reliability of findings across studies.

Results

29 studies met inclusion criteria, producing 36 odds ratios (ORs) comparing cessation outcomes across ENDS flavor groups. Three ORs examined quit intent, five examined quit attempts, and 28 examined quit success. Using GRADE, we reached Low levels of certainty that there was not an association between ENDS flavor use and intention to quit smoking or making a quit attempt. There were Very Low levels of certainty that nontobacco flavored versus tobacco/unflavored ENDS use was not associated with smoking cessation success, with similar findings for nonmenthol and nontobacco compared to tobacco and menthol flavored ENDS.

Conclusion

The evidence about the role of different flavored ENDS use and smoking cessation outcomes is inconclusive, reflecting highly heterogeneous study definitions and methodological limitations. More high-quality evidence, ideally from randomized controlled trials, is required.

A critique of the Australian National Health and Medical Research Council CEO statement on electronic cigarettes

This paper critically analyses a statement by Australia's National Health and Medical Research Council (NHMRC) on e-cigarettes in May 2022 that will be used to guide national policy. We reviewed the evidence and the conclusions drawn in the NHMRC Statement. In our view, the Statement is not a balanced reflection of the benefits and risks of vaping because it exaggerates the risks of vaping and fails to compare them to the far greater risks of smoking; it uncritically accepts evidence of harms from e-cigarettes while adopting a highly sceptical attitude towards evidence of their benefits; it incorrectly claims that the association between adolescent vaping and subsequent smoking is causal; and it understates the evidence of the benefits of e-cigarettes in assisting smokers to quit. The Statement dismisses the evidence that vaping is probably already having a positive net public health effect and misapplies the precautionary principle. Several sources of evidence supporting our assessment were published after the NHMRC Statement's publication and are also referenced. The NHMRC Statement on e-cigarettes does not present a balanced assessment of the available scientific literature and fails to meet the standard expected of a leading national scientific body.

Tobacco endgame intervention impacts on health gains and Māori:non-Māori health inequity: a simulation study of the Aotearoa/New Zealand Tobacco Action Plan

BACKGROUND

The Aotearoa/New Zealand Government is aiming to end the tobacco epidemic and markedly reduce Māori:non-Māori health inequalities by legislating: (1) denicotinisation of retail tobacco, (2) 95% reduction in retail outlets and (c) a tobacco free-generation whereby people born after 2005 are unable to legally purchase tobacco. This paper estimates future smoking prevalence, mortality inequality and health-adjusted life year (HALY) impacts of these strategies.

METHODS

We used a Markov model to estimate future yearly smoking and vaping prevalence, linked to a proportional multistate life table model to estimate future mortality and HALYs.

RESULTS

The combined package of strategies (plus media promotion) reduced adult smoking prevalence from 31.8% in 2022 to 7.3% in 2025 for Māori, and 11.8% to 2.7% for non-Māori. The 5% smoking prevalence target was forecast to be achieved in 2026 and 2027 for Māori males and females, respectively.The HALY gains for the combined package over the population's remaining lifespan were estimated to be 594 000 (95% uncertainty interval (UI): 443 000 to 738 000; 3% discount rate). Denicotinisation alone achieved 97% of these HALYs, the retail strategy 19% and tobacco-free generation 12%.By 2040, the combined package was forcat to reduce the gap in Māori:non-Māori all-cause mortality rates for people 45+ years old by 22.9% (95% UI: 19.9% to 26.2%) for females and 9.6% (8.4% to 11.0%) for males.

CONCLUSION

A tobacco endgame strategy, especially denicotinisation, could deliver large health benefits and dramatically reduce health inequities between Māori and non-Māori in Aotearoa/New Zealand.

Impact of the e-cigarette era on cigarette smoking among youth in the United States: A population-level study

To examine and compare trends in past 30-day cigarette smoking among adolescents in the US from 2002 to 2019, before and after the onset of the "e-cigarette era" in 2014. Using National Youth Tobacco Survey (NYTS) data from 2002 to 2019, we modeled the prevalence of past 30-day cigarette smoking over time. A total of n = 274,551 (weighted N = 340,403,754) middle and high school students were included in this study. Interrupted time series analyses were used to examine changes in cigarette smoking over time and compare trends in cigarette smoking pre- and post-2014. Models were applied to the full sample and stratified by middle (6th-8th grade) and high school (9th-12th grade). The observed number of current adolescent cigarette smokers post-2014 was compared to the predicted number, given trends in cigarette smoking prevalence observed pre-2014. Among all students, past 30-day cigarette smoking declined by approximately 0.75% per year from 2002 to 2013 (p < 0.001). Following a significant drop in prevalence from 2013 to 2014 (1.64%; p < 0.001), the decline in past 30-day cigarette smoking slowed significantly to approximately 0.37% per year (p < 0.001), from 2015 to 2019. We estimate that the onset of the "e-cigarette era" in 2014 corresponded to over 1.66 million (95% CI: 1.57 m - 1.75 m) more past 30-day cigarette smokers from 2015 to 2019, cumulatively. The rate of decline in past 30-day cigarette smoking prevalence among adolescents observed since 2002 slowed with the onset of the "e-cigarette era" in 2014, providing evidence at a population-level for the "gateway effect."

A Decision-Theoretic Public Health Framework for Heated Tobacco and Nicotine Vaping Products

Markets for nicotine vaping products (NVPs) and heated tobacco products (HTPs) have grown as these products became positioned as harm-reduction alternatives to combusted tobacco products. Herein, we present a public health decision-theoretic framework incorporating different patterns of HTP, NVP, and cigarette use to examine their impacts on population health. Our framework demonstrates that, for individuals who would have otherwise smoked, HTP use may provide public health benefits by enabling cessation or by discouraging smoking initiation and relapse. However, the benefits are reduced if more harmful HTP use replaces less harmful NVP use. HTP use may also negatively impact public health by encouraging smoking by otherwise non-smokers or by encouraging initiation or relapse into smoking. These patterns are directly influenced by industry behavior as well as public policy towards HTPs, NVPs, and cigarettes. While substantial research has been devoted to NVPs, much less is known about HTPs. Better information is needed to more precisely define the health risks of HTPs compared to cigarettes and NVPs, the relative appeal of HTPs to consumers, and the likelihood of later transitioning to smoking or quitting all products. While our analysis provides a framework for gaining that information, it also illustrates the complexities in distinguishing key factors.

The Australia Smoking and Vaping Model: The Potential Impact of Increasing Access to Nicotine Vaping Products

BACKGROUND

We model the potential impact of relaxing current nicotine vaping product (NVP) restrictions on public health in Australia.

AIMS AND METHODS

A Restricted NVP Scenario was first developed to project current smoking and vaping rates, where a U.S. smoking model was calibrated to recent Australian trends. To model less restrictive NVP policies, a Permissive NVP Scenario applied rates of switching from smoking to vaping, initiation into NVP and cigarette use, and cessation from smoking and vaping based on U.S. trends. The model measures vaping risk relative to the excess mortality rate of smoking. The public health impacts are measured as the difference between smoking- and vaping-attributable deaths (SVADs) and life years lost (LYLs) in the Restricted and Permissive NVP Scenarios. Sensitivity analysis is conducted regarding the NVP excess risk and other factors.

RESULTS

Assuming an NVP excess risk of 5% that of smoking, 104.2 thousand SVADs (7.7% reduction) and 2.05 million LYLs (17.3% reduction) are averted during 2017-2080 in the Permissive NVP Scenario compared to the Restricted NVP Scenario. Assuming 40% NVP excess risk, 70 thousand SVADs and 1.2 million LYLs are averted. The impact is sensitive to the rate at which smokers switch to NVPs and quit smoking, and relatively insensitive to the smoking initiation and NVP initiation and cessation rates.

CONCLUSIONS

The model suggests the potential for public health gains to be achieved by relaxing NVP access regulations. However, the model would benefit from better information regarding the impact of NVPs on smoking under a relaxation of current restrictions.

IMPLICATIONS

Australia has implemented a strong array of cigarette-oriented policies, but has restricted access to NVPs. The Smoking and Vaping Model offers a framework for modeling hypothetical policy scenarios. The Australian model shows the potential for public health gains by maintaining cigarette-oriented policies while relaxing the current restrictive NVP policy. Modeling results under a permissive NVP policy are particularly sensitive to the estimated rates of smoking cessation and switching to vaping, which are not well established and will likely depend on past and future cigarette-oriented policies and the specific NVP policies implemented in Australia.

Using Regulatory Stances to See All the Commercial Determinants of Health

Policy Points The commercial determinants of health (CDoH) concept, which currently focuses on markets that harm health, should be expanded to refer to the interface between commerce and health, which can sometimes have positive public health consequences. The regulatory stances framework helps us classify public health preferences for regulating specific markets related to CDoH, based on the intended effects of regulations on market size. The regulatory stances a jurisdiction can adopt can be classified as ranging from prohibitionist through contractionist, permissive, and expansionist, to universalist. The regulatory stances framework increases the usefulness of the CDoH concept by expanding the conversation beyond negative determinants of health and providing a fuller view of the tools at the disposal of society to alter markets and improve health.

CONTEXT

The effects of commerce on the public health are omnipresent. The commercial determinants of health (CDoH) represent a burgeoning area of scholarly debate and activist policymaking to redress markets that adversely affect public health. The CDoH debate is a logical extension of the tobacco control movement, but, to its detriment, the CDoH conversation remains primarily focused policies and proposals that are analogous to historical tobacco control strategies.

METHODS

This paper argues that for the CDoH to develop further and broaden its appeal, it should expand to cover markets with conditional and positive impacts on health. To explain and order this conversation, a comparative framework for regulatory policy is introduced: the regulatory stances. The regulatory stances classify a regulatory policy based on the intended effect of policy on the size of a market in the future relative to the present.

FINDINGS

Some markets that interface between commerce and health do not inherently harm health. Regulatory policy toward these markets should be different in intent than regulatory policy for markets with negative health effects.

CONCLUSIONS

By using the regulatory stances framework to encompass markets that have positive or conditional effects on health as well as those that have adverse health effects, the CDoH conversation can shift away from the exclusive focus on strategies to shrink markets with adverse health impacts to consider a wider array of policy options.

Closing the gaps in tobacco endgame evidence: a scoping review

OBJECTIVE

Tobacco endgame policies aim to rapidly and permanently reduce smoking to minimal levels. We reviewed evidence syntheses for: (1) endgame policies, (2) evidence gaps, and (3) future research priorities.

DATA SOURCES

Guided by JBI scoping review methodology, we searched five databases (PubMed, CINAHL, Scopus, Embase and Web of Science) for evidence syntheses published in English since 1990 on 12 policies, and Google for publications from key national and international organisations. Reference lists of included publications were hand searched.

STUDY SELECTION

Two reviewers independently screened titles and abstracts. Inclusion criteria were broad to capture policy impacts (including unintended), feasibility, public and stakeholder acceptability and other aspects of policy implementation.

DATA EXTRACTION

We report the results according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist.

DATA SYNTHESIS

Eight policies have progressed to evidence synthesis stage (49 publications): mandatory very low nicotine content (VLNC) standard (n=26); product standards to substantially reduce consumer appeal or remove the most toxic products from the market (n=1); moving consumers to reduced risk products (n=8); tobacco-free generation (n=4); ending sales (n=2); sinking lid (n=2); tax increases (n=7); and restrictions on tobacco retailers (n=10). Based on published evidence syntheses, the evidence base was most developed for a VLNC standard, with a wide range of evidence synthesised.

CONCLUSIONS

VLNC cigarettes have attracted the most attention, in terms of synthesised evidence. Additional focus on policies that reduce the availability of tobacco is warranted given these measures are being implemented in some jurisdictions.

Estimating the reduction in US mortality if cigarettes were largely replaced by e-cigarettes

BACKGROUND

Recent estimates indicated substantially replacing cigarettes by e-cigarettes would, during 2016-2100, reduce US deaths and life-years lost (millions) by 6.6 and 86.7 (Optimistic Scenario) and 1.6 and 20.8 (Pessimistic). To provide additional insight we use alternative modelling based on a shorter period (1991-2040), four main smoking-associated diseases, deaths aged 30-79 years, and a full product history. We consider variations in: assumed effective dose of e-cigarettes versus cigarettes (F); their relative quitting rate (Q); proportions smoking after 10 years (X); and initiation rate (I) of vaping, relative to smoking.

METHODS

We set F = 0.05, X = 5%, Q = 1.0 and I = 1.0 (Main Scenario) and F = 0.4, X = 10%, Q = 0.5 and I = 1.5 (Pessimistic Scenario). Sensitivity Analyses varied Main Scenario parameters singly; F from 0 to 0.4, X 0.01% to 15%, and Q and I 0.5 to 1.5. To allow comparison with prior work, individuals cannot be dual users, re-initiate, or switch except from cigarettes to e-cigarettes.

RESULTS

Main Scenario reductions were 2.52 and 26.23 million deaths and life-years lost; Pessimistic Scenario reductions were 0.76 and 8.31 million. These were less than previously, due to the more limited age-range and follow-up, and restriction to four diseases. Reductions in deaths (millions) varied most for X, from 3.22 (X = 0.01%) to 1.31 (X = 15%), and F, 2.74 (F = 0) to 1.35 (F = 0.4). Varying Q or I had little effect.

CONCLUSIONS

Substantial reductions in deaths and life-years lost were observed even under pessimistic assumptions. Estimates varied most for X and F. These findings supplement literature indicating e-cigarettes can importantly impact health challenges from smoking.

Improving on estimates of the potential relative harm to health from using modern ENDS (vaping) compared to tobacco smoking

BACKGROUND

Although the harm to health from electronic nicotine delivery systems (ENDS) compared to smoked tobacco remains highly uncertain, society and governments still need to know the likely range of the relative harm to inform regulatory policies for ENDS and smoking.

METHODS

We identified biomarkers with specificity of association with different disease groupings e.g., volatile organic compound (VOCs) for chronic obstructive pulmonary disease; and tobacco-specific N´-nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) for all cancers. We conducted a review of recent studies (post January 2017) that compared these biomarkers between people exclusively using ENDS and those exclusively smoking tobacco. The percentage differences in these biomarkers, weighted by study size and adjusted for acrolein from other sources, were used as a proxy for the assumed percentage difference in disease harm between ENDS and smoking. These relative differences were applied to previously modelled estimates of smoking-related health loss (in health-adjusted life-years; HALYs).

RESULTS

The respective relative biomarker levels (ENDS vs smoking) were: 28% for respiratory diseases (five results, three studies); 42% for cancers (five results, four studies); and 35% for cardiovascular (seven results, four studies). When integrated with the HALY impacts by disease, the overall harm to health from ENDS was estimated to be 33% that of smoking.

CONCLUSIONS

This analysis, suggests that the use of modern ENDS devices (vaping) could be a third as harmful to health as smoking in a high-income country setting. But this estimate is based on a limited number of biomarker studies and is best be considered a likely upper level of ENDS risk given potential biases in our method (i.e., the biomarkers used being correlated with more unaccounted for toxicants in smoking compared to with using ENDS).

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.

How Does the Use of Flavored Nicotine Vaping Products Relate to Progression Toward Quitting Smoking? Findings From the 2016 and 2018 ITC 4CV Surveys

INTRODUCTION

There is limited research on the role of flavors in nicotine vaping products (NVPs) in relation to smoking. We examined patterns of flavor use in NVPs in relation to progression toward quitting.

AIMS AND METHODS

Data come from 886 concurrent users of NVPs (at least weekly) and cigarettes who were first surveyed in 2016 and then successfully recontacted in 2018 as part of the ITC 4CV Surveys conducted in Australia, Canada, England, and the United States. Participants were asked about their main vaping flavor categorized as: (1) tobacco or unflavored, (2) menthol or mint flavored, and (3) "sweet" flavors (eg, fruit or candy). We examined whether flavor was associated with progression toward quitting smoking between survey years.

RESULTS

Overall, 11.1% of baseline concurrent users quit smoking by 2018. Compared with users of tobacco flavors, those vaping "sweet" flavors were more likely to quit smoking between surveys (13.8% vs. 9.6%; adjusted odds ratio [aOR] = 1.61, 95% confidence interval [CI] 1.01-2.58, p < .05), but those using menthol flavors were no more likely to quit smoking (8.3% vs. 9.6%, aOR = 0.87, 95% CI 0.43-1.47, p = .69). Among those who had quit smoking in 2018, 52.0% were still vaping, which was lower than the 65.8% among continuing smokers (aOR = 0.60, 95% CI 0.39-0.92, p = .02). Sweet flavor users were no more likely to continue vaping compared with tobacco flavor users, either for those continuing smoking or those having quit smoking by 2018. There was a net shift away from tobacco flavor among those who continued to vape at follow-up.

CONCLUSIONS

Use of fruit and other sweet flavored e-liquids is positively related to smokers' transition away from cigarettes.

IMPLICATIONS

With multiple jurisdictions considering limiting or banning the sale of flavored NVPs, it is important to consider how such policies may impact smokers using NVPs to transition away from cigarette smoking. Our results indicate that vapers who used sweet flavors were more likely to transition away from cigarette smoking and quit cigarette use, at least in the short term, compared with those who used tobacco or unflavored NVPs. Randomized clinical trials are needed to establish if the observed association between use of flavored e-liquids and smoking cessation is due to self-selection or is truly causal.

Regulatory approaches and implementation of minimally addictive combusted products

INTRODUCTION

A joint meeting was held by the World Health Organization (WHO) and the Convention Secretariat of the WHO Framework Convention on Tobacco Control to examine the potential effects of a regulatory policy to reduce nicotine in cigarettes to minimally addictive levels. This paper reviews the feasibility of and approaches to implementing a nicotine product standard.

METHODS

Prior WHO reports on this topic were consulted and a systematic review of the scientific literature was conducted. The paper was reviewed by the participants at the aforementioned meeting and their feedback was incorporated.

RESULTS

The nicotine dose most likely to consistently reduce smoking behavior and dependence is < 0.4 mg nicotine/g tobacco. An immediate rather than a gradual nicotine reduction approach appears to be more beneficial. Smokers are likely to seek nicotine from alternate sources (e.g., nicotine replacement therapies, e-cigarettes) or potentially, the illegal market. As such, the availability of alternative products, as well as strong policies against illegal markets, can potentially mitigate unintended consequences. An effective reduced nicotine regulation must be imbedded in a comprehensive and strong tobacco control program that includes public education and surveillance. Barriers and challenges to implementing a nicotine product standard exist, particularly in low-capacity countries.

CONCLUSION

Not all countries will have the capacity to implement a regulation to reduce nicotine in cigarettes (and preferably other combusted tobacco products) to minimally addictive levels. However, for the countries that choose to implement it, such a policy could potentially dramatically reduce the burden of tobacco use.

Public health implications of vaping in the USA: the smoking and vaping simulation model

Background

Nicotine vaping products (NVPs) are increasingly popular worldwide. They may provide public health benefits if used as a substitute for smoking, but may create public health harms if used as a gateway to smoking or to discourage smoking cessation. This paper presents the Smoking and Vaping Model (SAVM), a user-friendly model which estimates the public health implications of NVPs in the USA.

Methods

SAVM adopts a cohort approach. We derive public health implications by comparing smoking- and NVP-attributable deaths and life-years lost under a No-NVP and an NVP Scenario. The No-NVP Scenario projects current, former, and never smoking rates via smoking initiation and cessation rates, with their respective mortality rates. The NVP Scenario allows for smoking- and NVP-specific mortality rates, switching from cigarette to NVP use, separate NVP and smoking initiation rates, and separate NVP and smoking cessation rates. After validating the model against recent US survey data, we present the base model with extensive sensitivity analyses.

Results

The SAVM projects that under current patterns of US NVP use and substitution, NVP use will translate into 1.8 million premature smoking- and vaping-attributable deaths avoided and 38.9 million life-years gained between 2013 and 2060. When the NVP relative risk is set to 5%, the results are sensitive to the level of switching and smoking cessation rates and to a lesser extent smoking initiation rates. When the NVP relative risk is raised to 40%, the public health gains in terms of averted deaths and LYL are reduced by 42% in the base case, and the results become much more sensitive to variations in the base case parameters.

Discussion

Policymakers, researchers, and other public health stakeholders can apply the SAVM to estimate the potential public health impact of NVPs in their country or region using their own data sources. In developing new simulation models involving NVPs, it will be important to conduct extensive sensitivity analysis and continually update and validate with new data.

Conclusion

The SAVM indicates the potential benefits of NVP use. However, given the uncertainty surrounding model parameters, extensive sensitivity analysis becomes particularly important.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12963-021-00250-7.

Trends in Tobacco Use Among Adolescents by Grade, Sex, and Race, 1991-2019

IMPORTANCE

Use of e-cigarettes increased among adolescents between 2011 and 2019. However, whether these changes are affecting patterns of use of other tobacco products, especially cigarettes, remains unclear.

OBJECTIVE

To examine the long-term and recent trends in cigarette smoking and smokeless tobacco product use among US adolescents by grade (8th, 10th, and 12th), sex (male and female), and race (White and Black).

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, joinpoint regression analyses were performed to characterize trends in tobacco product use for key sociodemographic groups, identifying change of trend years (joinpoints). Students in the 8th, 10th, and 12th grades at US secondary schools and high schools who participated in the nationally representative Monitoring the Future survey from January 7, 1991, to June 3, 2019, were evaluated.

EXPOSURES

Cigarette smoking and smokeless tobacco product use during the past 30 days.

MAIN OUTCOMES AND MEASURES

Past 30-day and daily prevalence of cigarette smoking and smokeless tobacco product use by year, grade, sex, and race. The prevalence trend segments, change of trend years (joinpoints), and annual percentage change (APC) in prevalence within each trend segment were estimated using joinpoint regression.

RESULTS

Since 1991, 487 335 8th-grade, 447 310 10th-grade, and 424 236 12th-grade students have completed the Monitoring the Future survey (including 663 663 girls and 632 698 boys [those who did not respond to the sex question in the survey were excluded from the sex analyses]). Past 30-day and daily smoking prevalence increased in all groups analyzed from 1991 until 1996 and 1997 and has been decreasing ever since, with more rapid reductions in recent years. For example, daily smoking among 12th-grade boys increased at an APC of 4.9% (95% CI, 3.5%-6.3%) from 1991 to 1998, decreased at an APC of -8.0% (95% CI, -9.3% to -6.7%) from 1998 to 2006, decreased at an APC of -1.6% (95% CI, -4.6% to 1.5%) from 2006 to 2012, and decreased at an APC of -17.4% (95% CI, -19.4% to -15.4%) from 2012 to 2019. Similar results were observed for boys in the 8th grade (5.0% [95% CI, 0.1%-10.2%] for 1991-1996, -8.8% [95% CI, -10.0% to -7.6%] for 1996-2011, and -17.3% [95% CI, -22.2% to -12.0%] for 2011-2019) and 10th grade (7.1% [95% CI, 3.7%-10.7%] for 1991-1997, -11.1% [95% CI, -13.9% to -8.2%] for 1997-2005,-0.7% [95% CI, -5.9% to 4.9%] for 2005-2011, and -17.9 [95%, -21.7% to -13.9%] for 2011-2019), for girls in 8th grade (10.9% [95% CI, 5.0%-17.2%] for 1991-1996 and -10.8% [95% CI, -11.7% to -10.0% for 1996-2019), 10th grade (7.2% [95% CI, 3.9%-10.7%] for 1991-1997, -9.5% [95% CI, -10.5% to -8.6%] for 1997-2012, and -16.3% [95% CI, -21.8% to -10.4%] for 2012-2019), and 12th grade (6.5% [95% CI, 3.6%-9.5%] for 1991-1997, -7.2% [95% CI, -8.1% to -6.3%] for 1997-2012, and -17.5% [95% CI, -21.2% to -13.6%] for 2012-2019). Results were similar, too, for Black adolescents (2015-2019 average annual percentage change: -8.6% [95% CI, -10.3% to -6.8%] for 8th graders; -17.7% [95% CI, -26.3% to -8.2%] for 10th graders; and -18.3% [95% CI, -23.9% to -12.2%] for 12th graders) and White adolescents (2015-2019 average annual percentage change: -17.3% [95% CI, -20.6% to -13.7%] for 8th graders; -16.9% [95% CI, -20.5% to -13.2%] for 10th graders; and -17.0% [95% CI, -20.5% to -13.2%] for 12th graders). Smokeless tobacco was used more variably through 2012, followed by consistent decreases in the past 5 years. For instance, smokeless tobacco use in the past 30 days in 10th-grade boys decreased at an APC of -6.5% (95% CI, -7.5% to -5.4%) from 1991 to 2004, increased at an APC of 3.1% (95% CI, -0.8% to 7.1%) from 2004 to 2012, and decreased at an APC of -11.6% (95% CI, -15.7% to -7.4%) from 2012 to 2019. Similarly, daily smokeless tobacco use in 12th-grade boys decreased at an APC of -3.8% (95% CI, -5.4% to -2.1%) from 1992 to 2005, increased at an APC of 3.1% (95% CI, -0.2% to 6.5%) from 2005 to 2015, and decreased at an APC of -23.0% (95% CI, -33.3% to -11.0%) from 2015 to 2019.

CONCLUSIONS AND RELEVANCE

This cross-sectional study suggests that, despite the increase in the prevalence of e-cigarette use among adolescents between 2011 and 2019, the prevalence of cigarette and smokeless tobacco use has decreased more rapidly during the same period compared with earlier years.