Risk and safety profile of electronic nicotine delivery systems (ENDS): an umbrella review to inform ENDS health communication strategies

Current perspective on e-cigarette use and respiratory outcomes: mechanisms and messaging

INTRODUCTION

There has been an increasing amount of research on the consequences of e-cigarette use for respiratory outcomes, which is significant for public health and respiratory medicine. We discuss recent findings and lay out implications for prevention and treatment.

AREAS COVERED

Based on literature searches using several databases (PubMed, Web of Science, Google Scholar) for keywords, including synonyms, 'e-cigarettes,' with 'pulmonary function,' 'oxidative stress,' and 'inflammation,' we review studies on acute effects of e-cigarette use for measures of pulmonary function and discuss selected laboratory studies on mechanisms of effect, focusing on processes with known relation to respiratory disease; oxidative stress and inflammation. We discuss available studies that have tested the effectiveness of communication strategies for prevention of e-cigarette use oriented to different audiences, including nonsmoking adolescents and adult smokers.

EXPERT OPINION

We conclude that the evidence presents a mixed picture. Evidence is found for adverse consequences of e-cigarette use on measures of lung function and two disease-related biological processes, sometimes but not always less than for cigarette smoking. How to best communicate these results to a complex audience of users, from younger susceptible adolescents to long-term adult smokers interested in quitting, is a question of significant interest and empirically validated communication strategies are greatly needed.

[Harmful health effects of flavors in e-cigarettes]

BACKGROUND

Almost all e-cigarettes contain flavorings that make the product more attractive. In the evaluation of e-cigarettes on health, flavors have so far played a subordinate role.

METHOD

Selective literature search in PubMed, supplemented by legal regulations on the use of flavors in e-cigarettes.

RESULTS

Flavors make it easier to start using e-cigarettes and have a consumption-promoting effect. Deeper inhalation increases nicotine uptake and the absorption of toxic substances from the e-cigarette liquid. For some flavors, pathological effects have been demonstrated in addition to other toxic components of the e-cigarette. To date, no toxicological analyses are available for the vast majority of flavors contained in e-cigarettes.

CONCLUSIONS

The proven consumption-promoting effect and the health risks that can be extrapolated from preclinical data are significant for the political discussion of a ban on flavors for e-cigarettes, analogous to the ban on flavors in tobacco products already in force.

[Harmful health effects of flavors in e-cigarettes]

BACKGROUND

 Almost all e-cigarettes contain flavorings that make the product more attractive. In the evaluation of e-cigarettes on health, flavors have so far played a subordinate role.

METHOD

 Selective literature search in PubMed, supplemented by legal regulations on the use of flavors in e-cigarettes.

RESULTS

 Flavors make it easier to start using e-cigarettes and have a consumption-promoting effect. Deeper inhalation increases nicotine uptake and the absorption of toxic substances from the e-cigarette liquid. For some flavors, pathological effects have been demonstrated in addition to other toxic components of the e-cigarette. To date, no toxicological analyses are available for the vast majority of flavors contained in e-cigarettes.

CONCLUSIONS

 The proven consumption-promoting effect and the health risks that can be extrapolated from preclinical data are significant for the political discussion of a ban on flavors for e-cigarettes, analogous to the ban on flavors in tobacco products already in force.

Longitudinal impact of perceived harm and addiction on e-cigarette initiation among tobacco-naïve youth: Population Assessment of Tobacco and Health study (Waves 1-5)

OBJECTIVES

This study investigates the effect of e-cigarette-related harm and addiction perceptions on e-cigarette initiation among US tobacco-naïve adolescents.

STUDY DESIGN

This is a longitudinal study.

METHODS

Using data from five waves (2013-2019) of the Population Assessment of Tobacco and Health Study, we created a longitudinal data set for 2775 youth aged 12-17 years who had no prior use of tobacco products at Wave 1. E-cigarette initiation was defined as transitioning from non-use at Wave 1 to ever use in subsequent waves. Kaplan-Meier survival and Cox proportional hazard regression models were used to assess the impact of harm and addiction perceptions on e-cigarette initiation.

RESULTS

Our analytic sample comprised 63.1% of youth who had never used tobacco products at Wave 1 and consequently initiated e-cigarette use in subsequent waves. Over time, fewer individuals perceived e-cigarettes as harmless (14.1%-2.1%), whereas more perceived them as likely to cause addiction (53.7%-76.6%). Compared with perceiving e-cigarettes as a lot of harm, those perceiving some harm (adjusted hazard ratio [aHR] = 1.30, 95% confidence interval [CI]: 1.12-1.52), little harm (aHR = 1.42, 95% CI: 1.20-1.68), or no harm (aHR = 2.09, 95% CI: 1.64-2.65) were more likely to initiate e-cigarette use. Demographic factors for initiation included being Black or Hispanic ethnicity (vs White), younger age (12-14 vs15-17 years), and receiving over $20 per week (vs $0) in pocket money, with P-values <0.05. However, in adjusted results, addiction perceptions did not significantly impact e-cigarette initiation (P-values >0.05).

CONCLUSIONS

Among youth without prior tobacco/nicotine use, perceiving e-cigarettes as having low harm significantly predicted initiation over time. Effective prevention strategies, including targeted risk communication interventions, are essential for discouraging e-cigarette use among youth.

[Use of tobacco cigarettes, e-cigarettes, and shishas among children and adolescents: Results of the 'Präventionsradar' from 2016 to 2023]

AIM

To measure trends in the use of various smoking products among children and adolescents from 2016 to 2023.

METHOD

The data is based on seven waves of the "Präventionsradar", a school-based epidemiological study in grades 5 to 10. The primary endpoints of the study were the lifetime and monthly prevalence of the use of tobacco cigarettes, e-cigarettes, shisha and the use of at least two of these smoking products (combined use). Prevalence estimates are based on logistic regression models.

RESULTS

The analysis was based on 94,127 questionnaires. The sex ratio was balanced (49% female), mean age was 13 years (SD=1.8). In 2022/2023, the lifetime prevalence of smoking tobacco cigarettes was 18.8% (95% CI 18.1-19.5), of e-cigarettes 23.5% (95% CI 22.8-24.3), of shisha 14.0% (95% CI 13.4-14.7) and combined use 19.0% (95% CI 18.3-19.7). The monthly prevalence of smoking tobacco cigarettes was 5.9% (95% CI 5.5-6.4), of e-cigarettes 7.0% (95% CI 6.5-7.4), of shisha 3.2% (95% CI 2.8-3.5) and combined use 4.8% (95% CI 4.4-5.2). The following trends in lifetime prevalence have emerged since 2016: tobacco cigarettes (-3.0 percentage points), e-cigarettes (+1.8 percentage points), shisha (-9.2 percentage points), combined use (-2.7 percentage points). In the years of the COVID-19 pandemic, youth smoking decreased and rose again post-COVID with the exception of shisha.

DISCUSSION

The use of smoking products in adolescence occurs frequently. Over the observational period, a trend reversal towards e-cigarettes as the most popular product among children and young people is most likely. In addition, the combined use of several smoking products has become a common pattern of consumption. Consistent preventive measures are required in order to achieve the goal of a smoke-free society in 2040.

Building consensus on a set of ENDS-specific pictorial health warnings: a Delphi study among a tobacco control expert panel

BACKGROUND

This study reports on the development of pictorial health warning labels for electronic nicotine delivery system (ENDS) using the Delphi approach with a panel of tobacco control experts. Twenty-four evidence-based ENDS-specific warnings corresponding to three themes (toxicity, health risks and specific harm) were developed and used in the Delphi study.

METHODS

We conducted a three-round online Delphi study among 60 experts (55% female) between June 2022 and April 2023. We balanced the panel in areas of expertise and positions relevant to ENDS (risks, benefits). In round 1, participants rated the warnings on attention, relevance to evidence and perceived effectiveness (harm perception, motivation to quit) and provided suggestions for improvement. In rounds 2 and 3, participants ranked the revised warnings based on importance in each theme. We assessed levels of agreement between participants using interquartile deviations and medians.

RESULTS

Warnings in theme 1, toxicity, received the highest ratings for perceived effectiveness on harm perception and encouraging quitting ENDS (p<0.05). Experts recommended using clear and affirmative text paired with emotion-provoking pictures and avoiding the rare side effects of ENDS. Most of the top-ranked warnings were from theme 3, ENDS-specific harm, pertained to lung damage, dual use of ENDS and cigarettes, nicotine addiction among youth, anti-ENDS industry sentiment and toxicity.

DISCUSSION

This study developed 24 evidence-based ENDS health warning labels using a systematic process that included several rounds of expert panel feedback. These warnings can be used to advance ENDS prevention and tobacco control policies and further target different populations.

Regional socioeconomic deprivation in Germany and nicotine use among children and adolescents

To assess the association of regional socioeconomic deprivation and nicotine use, survey data from 17,877 pupils aged 9-17 years were analysed. Lifetime use of combustible, e-cigarettes, and both products were the outcome variables. The German Index of Socioeconomic Deprivation was the exposure variable. Logistic regression models controlling for age, gender, school type, and sensation seeking were used to examine associations between regional socioeconomic deprivation and nicotine use. Ever use of combustible cigarettes was 17.8%, of e-cigarettes 19.6%, and of both products 13.4%. Compared to the most affluent area, the adjusted odds ratio of combustible cigarette use in the most deprived area was 2.24 (95% CI: 1.67-3.00), of e-cigarette use 1.56 (95% CI: 1.20-2.03), and of poly use 1.91 (95% CI: 1.36-2.69). Nicotine use among young people across ages and especially in socioeconomic-deprived areas was widespread. Nicotine control measures are urgently needed to reduce smoking and vaping in German adolescents.

Youth Exposure and Response to the FDA Health Warning Label on Electronic Cigarettes Packaging: Policy Implications

INTRODUCTION

Youth represent a high-priority group for e-cigarette health communication. This study examined youth exposure to the Food and Drug Administration (FDA) e-cigarette warning label over 4 years and its association with change in youth harm perception and intention.

AIMS AND METHODS

We pooled data from the 2018-2021 National Youth Tobacco Survey (age 10-17; n = 67 159). Participants were divided into four groups: never users (58.5%), susceptible nonusers (16.3%), former users (12.7%), and current users (12.5%). We examined the prevalence, time-trend, correlates, and association of youth exposure to the warning with addictiveness and harm perception, intention to use e-cigarettes, and intention to quit all tobacco products.

RESULTS

Only 24.5% of youth were exposed to the warning. Exposure increased from 14.9% in 2018 to 30.8% in 2019, then declined to 25.2% in 2021. Hispanic (adjusted odds ratio (aOR) = 0.76 [95% CI = 0.641 to 0.89]) and non-Hispanic black current users (0.53 [0.40 to 0.69]) were less likely to be exposed to the warning than white current users. Youth exposure was positively associated with a higher perception of e-cigarette addictiveness (1.12 [1.04 to 1.19]) and intention to quit all tobacco products (1.28 [1.13 to 1.46]). However, exposure was negatively associated with harm perception (0.91 [0.85 to 0.96]) and the intention to use e-cigarettes among e-cigarette nonusers (2.38 [1.99 to 2.84]).

CONCLUSIONS

The decline in youth exposure to the warning indicates wear-out effects. Strengthening the label by using compelling designs, adding themes on e-cigarette harm to youth, periodically rotating warning content, and using culturally tailored messaging may improve its impact on youth and address racial/ethnic disparities.

IMPLICATIONS

The FDA e-cigarette label reached only 24.5% of youth, and exposure to the warning declined to indicate wear-out effects. Exposure was significantly lower among minorities. Exposure was associated with a higher perception of e-cigarette addictiveness and intention to quit all tobacco products. Still, it did not increase harm perception or reduce intention to use e-cigarettes among nonusers. Strengthening the label by using more compelling designs, including diverse themes focusing on e-cigarette harm relevant to youth, and periodically rotating warning content may improve its impact on youth. Continued surveillance of the implementation of e-cigarette policies is needed to ensure that they equally affect youth across racial/ethnic subpopulations.

Electronic cigarette use in relation to changes in smoking status and respiratory symptoms

INTRODUCTION

How e-cigarette use relates to changes in smoking status and respiratory symptoms in the population remains controversial. The aim was to study the association between e-cigarette use and, changes in smoking status and changes in respiratory symptoms.

METHODS

A prospective, population-based study of random samples of the population (age 16-69 years) was performed within The Obstructive Lung Disease in Northern Sweden (OLIN) study and West Sweden Asthma Study (WSAS). A validated postal questionnaire containing identical questions was used in OLIN and WSAS at baseline in 2006-2008 and at follow-up in 2016. In total, 17325 participated on both occasions. Questions about respiratory symptoms and tobacco smoking were included in both surveys, while e-cigarette use was added in 2016.

RESULTS

In 2016, 1.6% used e-cigarettes, and it was significantly more common in persistent tobacco smokers (10.6%), than in those who quit smoking (2.1%), started smoking (7.8%), or had relapsed into tobacco smoking at follow-up (6.4%) (p<0.001). Among current smokers at baseline, tobacco smoking cessation was less common in e-cigarette users than e-cigarette non-users (14.2% vs 47.6%, p<0.001) and there was no association with a reduction in the number of tobacco cigarettes smoked per day. Those who were persistent smokers reported increasing respiratory symptoms. In contrast, the symptoms decreased among those who quit tobacco smoking, but there was no significant difference in respiratory symptoms between quitters with and without e-cigarette use.

CONCLUSIONS

E-cigarette use was associated with persistent tobacco smoking and reporting respiratory symptoms. We found no association between e-cigarette use and tobacco smoking cessation, reduction of number of tobacco cigarettes smoked per day or reduction of respiratory symptoms.

[Use of tobacco cigarettes, e-cigarettes, and shishas among children and adolescents: Results of the 'Präventionsradar' from 2016 to 2023]

AIM

To measure trends in the use of various smoking products among children and adolescents from 2016 to 2023.

METHOD

The data is based on seven waves of the "Präventionsradar", a school-based epidemiological study in grades 5 to 10. The primary endpoints of the study were the lifetime and monthly prevalence of the use of tobacco cigarettes, e-cigarettes, shisha and the use of at least two of these smoking products (combined use). Prevalence estimates are based on logistic regression models.

RESULTS

The analysis was based on 94,127 questionnaires. The sex ratio was balanced (49% female), mean age was 13 years (SD=1.8). In 2022/2023, the lifetime prevalence of smoking tobacco cigarettes was 18.8% (95% CI 18.1-19.5), of e-cigarettes 23.5% (95% CI 22.8-24.3), of shisha 14.0% (95% CI 13.4-14.7) and combined use 19.0% (95% CI 18.3-19.7). The monthly prevalence of smoking tobacco cigarettes was 5.9% (95% CI 5.5-6.4), of e-cigarettes 7.0% (95% CI 6.5-7.4), of shisha 3.2% (95% CI 2.8-3.5) and combined use 4.8% (95% CI 4.4-5.2). The following trends in lifetime prevalence have emerged since 2016: tobacco cigarettes (-3.0 percentage points), e-cigarettes (+1.8 percentage points), shisha (-9.2 percentage points), combined use (-2.7 percentage points). In the years of the COVID-19 pandemic, youth smoking decreased and rose again post-COVID with the exception of shisha.

DISCUSSION

The use of smoking products in adolescence occurs frequently. Over the observational period, a trend reversal towards e-cigarettes as the most popular product among children and young people is most likely. In addition, the combined use of several smoking products has become a common pattern of consumption. Consistent preventive measures are required in order to achieve the goal of a smoke-free society in 2040.

[Electronic cigarettes: harm reduction or harm prolongation?]

This paper deals with the question of whether electronic cigarettes (e-cigarettes) can minimize the proven harm of smoking tobacco or may lead to a long-term harm. While the British Royal College of Physicians recommends smokers to use e-cigarettes as a substitute for tobacco products, the German Society for Pneumology and Respiratory Medicine advises smokers against using e-cigarettes. The harm reduction strategy is based on three hypotheses. Hypothesis 1: It is assumed that e-cigarettes cause less damage to health than tobacco cigarettes. Hypothesis 2: It is postulated that smokers are motivated to switch from conventional cigarettes to e-cigarettes. Hypothesis 3: It is assumed that e-cigarettes are an effective means for quitting smoking with few side effects. Although the long-term health consequences of e-cigarette use remain unknown, there is increasing evidence that e-cigarettes are toxic, harmful to cardiovascular system, respiratory health and potentially carcinogenic. Population-representative epidemiological surveys have shown that three-quarters of all current e-cigarette users in Germany smoke tobacco at the same time. In a few randomized clinical trials, e-cigarettes showed higher success rates compared to nicotine replacement products. As over-the-counter consumer products, a large number of studies have found no advantage for e-cigarettes under real conditions. In addition, e-cigarettes prolong nicotine dependence compared to nicotine replacement products. According to the current state of knowledge, the hypotheses behind the harm minimization strategy using e-cigarettes must be regarded as refuted. It therefore appears ethically problematic when doctors recommend e-cigarettes to their patients as a substitute for smoking.

Understanding Determinants of Electronic Cigarette and Heated Tobacco Product Use among Young Adults in Lebanon: Prevention and Policy Implications

In line with the global trends, electronic cigarettes (e-cigarettes) and heated tobacco products (HTPs) have found their way to the Lebanese market. The present study aims to explore the determinants of e-cigarette and HTP use among young adults in Lebanon. Convenience and snowball sampling were used to recruit participants aged 18-30 residing in Lebanon, who were familiar with e-cigarettes products. Twenty-one consenting participants were interviewed via Zoom and the verbatim transcriptions were analyzed thematically. The outcome expectancy theory was used to categorize the results into determinants and deterrents of use. HTPs were viewed by participants as another mode of smoking. The results showed that most participants perceived e-cigarettes and HTPs to be healthier alternatives to cigarettes/waterpipes and to be used as smoking cessation tools. Both e-cigarettes and HTPs were found to be easily accessible in Lebanon; although, in the recent economic crisis, e-cigarettes have become unaffordable. More research is needed to investigate the motivations and behaviors of e-cigarette and HTP users if effective policies and regulations are to be developed and enforced. Furthermore, greater public health efforts need to be made to increase awareness of the harmful impacts of e-cigarettes and HTPs and to implement evidence-based cessation programs tailored to those modes of smoking.

Del consumo ocasional del tabaco a la adicción a la nicotina

Introducción. El consumo ocasional de nicotina puede generar una dependencia o adicción, siendo detectable mediante modificaciones en los mecanismos neurobiológicos. Objetivo. Contextualizar del consumo a la adicción e identificar teóricamente el  mecanismo neurobiológico de transición del consumo regular del tabaco a la adicción de la nicotina. Metodología. Se realizó una búsqueda de artículos en inglés y español usando diferentes bases de datos y combinaciones de palabras clave, se seleccionaron los artículos que describieran las características de los procesos neurobiológicos implicados en el uso o consumo intermitentedel tabaco a la adicción a la nicotina como el tema principal. Resultados. El número de investigaciones relacionados a este tema es reducido, aún más en relación con la descripción de los procesos y cambios neurales de la adicción a la nicotina. La adicción a las drogas es un proceso neuroconductual complejo que altera los circuitos del sistema de motivaciónrecompensa del cerebro, por la disminución de la dopamina y la afectación en la regulación del glutamato en los ganglios basales y extensión de la amígdala se asocia con el craving, la anticipación y el déficit en la función ejecutiva. Conclusiones. El tabaco está considerado como una droga legal, por lo que su consumo pareciera ser inofensivo. Sin embargo, las evidencias muestran que su consumo a largo plazo tiene consecuencias graves en la salud de los individuos. El entender cómo cambia el hábito de fumar ocasionalmente al consumocrónico nos hace más conscientes sobre las adaptaciones en el cerebro.

Electronic Nicotine Delivery Systems (ENDS) use Among Members of a Community Engagement Program

Electronic nicotine delivery systems (ENDS) are relatively new and ENDS use data from community engagement programs may help us understand usage patterns and facilitate targeted longitudinal studies. Community members in Florida, USA, were asked about ENDS use, tobacco use, and health history/concerns by Community Health Workers. Among 7253 members recruited during 2014 to 2021 into our HealthStreet program, 1177 had ever used ENDS; the proportion increased from 12 to 27% from 2014 to 2021 (adjusted odds ratio (aOR) 2.5; 95% CI 1.7-3.5; Ever versus never used ENDS). Ever tobacco use was strongly associated with ENDS use; 69% of ever users were current tobacco users. Demographic determinants (sex, age, race) and food insecurity were strongest predictors of ENDS use. Most who had ever used ENDS were aged 18-25 (aOR 5.9; 95% CI 4.6-7.6; vs. aged 60 + years), White (aOR 3.7; 95% CI 3.2-4.3; vs. Black/African American), male (aOR 1.5; 95% CI 1.3-1.7; vs. female), and recently food insecure (aOR 1.8; 95% CI 1.5-2.0; vs. not recently food insecure). Those with respiratory issues were more likely to have used ENDS compared to those without (aOR 2.0; 95% CI 1.6-2.6; aOR 1.3; 95% CI 1.1-1.5). Members concerned about hypertension were less likely to have used ENDS (aOR 0.7; 95% CI 0.5-0.9). In this relatively rural, micropolitan sample, tobacco use, socio-economic determinants, and certain health history/concerns were strongly associated with ENDS use. Community outreach approaches are needed to further understand these factors and implement interventions.