The Promise and Peril of Vaping

Factors influencing JUUL e-cigarette nicotine vapour-induced reward, withdrawal, pharmacokinetics and brain connectivity in rats: sex matters

Though vaping likely represents a safer alternative to smoking, it is not without risks, many of which are not well understood, especially for vulnerable populations. Here we evaluate the sex- and age-dependent effects of JUUL nicotine vapour in rats. Following passive nicotine vapour exposures (from 59 mg/ml JUUL nicotine pods), rats were evaluated for reward-like behaviour, locomotion, and precipitated withdrawal. Pharmacokinetics of nicotine and its metabolites in brain and plasma and the long-term impact of nicotine vapour exposure on functional magnetic resonance imaging-based brain connectivity were assessed. Adult female rats acquired conditioned place preference (CPP) at a high dose (600 s of exposure) of nicotine vapour while female adolescents, as well as male adults and adolescents did not. Adult and adolescent male rats displayed nicotine vapour-induced precipitated withdrawal and hyperlocomotion, while both adult and adolescent female rats did not. Adult females showed higher venous and arterial plasma and brain nicotine and nicotine metabolite concentrations compared to adult males and adolescent females. Adolescent females showed higher brain nicotine concentration compared to adolescent males. Both network-based statistics and between-component group connectivity analyses uncovered reduced connectivity in nicotine-exposed rats, with a significant group by sex interaction observed in both analyses. The short- and long-term effects of nicotine vapour are affected by sex and age, with distinct behavioural, pharmacokinetic, and altered network connectivity outcomes dependent on these variables.

The commercial promotion of electronic cigarettes on social media and its influence on positive perceptions of vaping and vaping behaviours in Anglophone countries: A scoping review

There is ongoing scientific and policy debate about the role e-cigarettes play in tobacco control, with concerns centring around unknown long-term effects, and the potential industry co-option of harm reduction efforts, including marketing to youths. There is substantial evidence of the influence of conventional cigarette promotion on smoking behaviours in Anglophone countries, and the popularity of social networking sites, as well as the lack of marketing regulations on the commercial promotion of electronic cigarettes online, suggest an urgent need to explore this topic further. This scoping review aims to map the existing evidence related to the influence of e-cigarette commercial promotion on social media on positive perceptions of vaping and vaping behaviours in core Anglophone countries. Searches were conducted in CENTRAL, Cochrane Database of Systematic Reviews (CDSR), Embase, Epistemonikos, MEDLINE, PsycINFO and Science Citation Index, on the 21st of July 2022. From 1,385 studies, 11 articles were included in the final review, using diverse study designs, including focus groups, content analysis, cross-sectional studies, and experiments. The studies were primarily based in the U.S. and evidenced the association between the commercial promotion of e-cigarettes on social media with positive perceptions of vaping and vaping behaviours, particularly among young people, addressing diverse themes including celebrities' sponsorship, e-liquid appeal (including flavours and nicotine levels), users' engagement with ads, and other marketing strategies. Further, social networking sites commercially promoting e-cigarettes might increase positive attitudes towards vaping and vaping behaviours, particularly among youths. Future research should be conducted in broader settings, incorporate larger and diverse sample sizes, ensure research transparency, cover multiple social networking sites, emphasize ecological validity, and foment longitudinal studies.

Ethics and ENDS

As debate persists over regulating electronic nicotine delivery systems (ENDS), those favouring liberal ENDS policies have advanced rights-based arguments privileging harm reduction to people who smoke over harm prevention to children and never-smokers. Recent ethical arguments advocate regulating ENDS to prioritise their harm reduction potential for people who currently smoke over any future harm to young never-smokers. In this article, we critically assess these arguments, in particular, the assumption that ethical arguments for prioritising the interests of young people do not apply to ENDS. We argue that, when the appropriate comparators are used, it is not clear the weight of ethical argument tips in favour of those who currently smoke and against young never-smokers. We also assert that arguments from a resource prioritisation context are not appropriate for analysing ENDS regulation, because ENDS are not a scarce resource. Further, we reject utilitarian arguments regarding maximising net population health benefits, as these do not adequately consider vulnerable groups' rights, or address the population distribution of benefits and harms. Lastly, we argue that one-directional considerations of harm reduction do not recognise that ENDS potentially increase harm to those who do not smoke and who would not otherwise have initiated nicotine use.

Use of Vaping as a Smoking Cessation Aid: A Review of Clinical Trials

Purpose

Smoking is a global public health concern, with a significant negative impact on human health and healthcare spending. Vaping, or the use of electronic cigarettes (e-cigarettes), has emerged as a popular alternative to traditional nicotine replacement therapies (NRTs) for smoking cessation. While considered less harmful than combustible cigarettes, the long-term health effects of e-cigarettes (vaping) are unknown. Therefore, this study aimed to identify and provide a comprehensive overview of the performance of vaping in clinical trials.

Patients and Methods

A search was conducted in the ClinicalTrials.gov database on April 14th, 2023, using the search term "smoking cessation, e-cigarettes, NRTs, and vaping". Inclusion and exclusion criteria were defined to identify relevant clinical trials. Randomized controlled trials (RCTs) and non-randomized clinical trials that evaluated vaping as a therapeutic approach to smoking cessation were included.

Results

A total of 87 clinical trials were identified, of which only seven were related to smoking cessation through vaping as a form of treatment. The primary endpoint was the effect of vaping as smoking cessation, and the secondary endpoints were patients' abstinence rate, withdrawal symptoms, and adverse events of e-cigarettes. Most of the trials used e-cigarettes as an intervention, with some trials including a combination of e-cigarettes and other NRTs. The trials lasted from 4 weeks to 12 months. The overall results of the trials indicated that vaping was effective in helping smokers to quit. It was also associated with a lower risk of adverse events than combustible cigarettes.

Conclusion

Vaping appears to be an effective method for smoking cessation, and it is associated with a lower risk of adverse events than combustible cigarettes.

Measuring vaping-related expectancies in young adults: Psychometric evaluation of the Electronic Nicotine Vaping Outcomes (ENVO) scale

OBJECTIVE

Electronic cigarettes are the most commonly used tobacco products by young adults. Measures of beliefs about outcomes of use (i.e., expectancies) can be helpful in predicting use, as well as informing and evaluating interventions to impact use.

METHODS

We surveyed young adult students (N = 2296, Mean age=20.0, SD=1.8, 64 % female, 34 % White) from a community college, a historically black university, and a state university. Students answered ENDS expectancy items derived from focus groups and expert panel refinement using Delphi methods. Factor Analysis and Item Response Theory (IRT) methods were used to understand relevant factors and identify useful items.

RESULTS

A 5-factor solution [Positive Reinforcement (consists of Stimulation, Sensorimotor, and Taste subthemes, α = .92), Negative Consequences (Health Risks and Stigma, α = .94), Negative Affect Reduction (α = .95), Weight Control (α = .92), and Addiction (α = .87)] fit the data well (CFI=0.95; TLI=0.94; RMSEA=0.05) and was invariant across subgroups. Factors were significantly correlated with relevant vaping measures, including vaping susceptibility and lifetime vaping. Hierarchical linear regression demonstrated factors were significant predictors of lifetime vaping after controlling for demographics, vaping ad exposure, and peer/family vaping. IRT analyses indicated that individual items tended to be related to their underlying constructs (a parameters ranged from 1.26 to 3.18) and covered a relatively wide range of the expectancies continuum (b parameters ranged from -0.72 to 2.47).

CONCLUSIONS

A novel ENDS expectancy measure appears to be a reliable measure for young adults with promising results in the domains of concurrent validity, incremental validity, and IRT characteristics. This tool may be helpful in predicting use and informing future interventions.

IMPLICATIONS

Findings provide support for the future development of computerized adaptive testing of vaping beliefs. Expectancies appear to play a role in vaping similar to smoking and other substance use. Public health messaging should target expectancies to modify young adult vaping behavior.

Misconceptions of Vaping Among Young Adults

Background Vaping is growing in popularity worldwide, especially among young adults. To develop effective tobacco prevention interventions, first, there must be an understanding of the attitudes and perceptions of young adults toward the use of vaping. Highlighting perception discrepancies between races may allow physicians to more effectively counsel their patients regarding the risks of vaping. Methodology We conducted an online survey using Amazon Mechanical Turk (MTurk, https://www.mturk.com/) to identify misconceptions about vaping among adults aged 18 to 24 years who currently vape. The survey consisted of 18 questions evaluating reasons for vaping, history of tobacco use, and thoughts on the adverse effects of vaping. The Penn State Electronic Cigarette Dependence Index was implemented to assess dependence. Exclusion criteria comprised respondents who did not vape and were under the age of 18 or over the age of 24. Results A total of 1,009 responses were received with 66% identifying as male (n = 667) and 33% (n = 332) identifying as female. Sixty-nine percent of patients smoked cigarettes or used another form of tobacco previously (n = 692). Of those respondents, 81% indicated that they had since quit using tobacco products (excluding vaping). Switching to vaping was the most common reason for quitting cigarettes or other forms of tobacco, with health concerns and social purposes being the second and third most common reasons provided, respectively. When asked whether vaping had negative health impacts, only 238 (24%) participants strongly agreed with this statement, while a majority (64%) neither agreed nor disagreed or only somewhat agreed. Most participants were white or Caucasian (n = 777). When asked whether smoking or vaping had more severe health implications, 55% of white or Caucasian participants, 41% of Asian participants, and 32% of black or African American participants indicated that vaping was worse than smoking cigarettes. The average Penn State dependence score was 8.7, suggesting medium dependence. Conclusions Our survey sample of 1,006 young adults who vape indicated that the majority did not perceive vaping as significantly harmful. A comprehensive smoking prevention policy, educational interventions, and quit support are needed to enhance awareness among young adults about the health effects associated with vaping. Such interventions should also consider the novel shift toward the replacement of smoking with vaping.

E-liquids and vanillin flavoring disrupts retinoic acid signaling and causes craniofacial defects in Xenopus embryos

Environmental teratogens such as smoking are known risk factors for developmental disorders such as cleft palate. While smoking rates have declined, a new type of smoking, called vaping is on the rise. Vaping is the use of e-cigarettes to vaporize and inhale an e-liquid containing nicotine and food-like flavors. There is the potential that, like smoking, vaping could also pose a danger to the developing human. Rather than waiting for epidemiological and mammalian studies, we have turned to an aquatic developmental model, Xenopus laevis, to more quickly assess whether e-liquids contain teratogens that could lead to craniofacial malformations. Xenopus, like zebrafish, has the benefit of being a well-established developmental model and has also been effective in predicting whether a chemical could be a teratogen. We have determined that embryonic exposure to dessert flavored e-liquids can cause craniofacial abnormalities, including an orofacial cleft in Xenopus. To better understand the underlying mechanisms contributing to these defects, transcriptomic analysis of the facial tissues of embryos exposed to a representative dessert flavored e-liquid vapor extract was performed. Analysis of differentially expressed genes in these embryos revealed several genes associated with retinoic acid metabolism or the signaling pathway. Consistently, retinoic acid receptor inhibition phenocopied the craniofacial defects as those embryos exposed to the vapor extract of the e-liquid. Such malformations also correlated with a group of common differentially expressed genes, two of which are associated with midface birth defects in humans. Further, e-liquid exposure sensitized embryos to forming craniofacial malformations when they already had depressed retinoic acid signaling. Moreover, 13-cis-retinoic acid treatment could significantly reduce the e-liquid induced malformation in the midface. Such results suggest the possibility of an interaction between retinoic acid signaling and e-liquid exposure. One of the most popular and concentrated flavoring chemicals in dessert flavored e-liquids is vanillin. Xenopus embryos exposed to this chemical closely resembled embryos exposed to dessert-like e-liquids and a retinoic acid receptor antagonist. In summary, we determined that e-liquid chemicals, in particular vanillin, can cause craniofacial defects potentially by dysregulating retinoic acid signaling. This work warrants the evaluation of vanillin and other such flavoring additives in e-liquids on mammalian development.

Comparing belief in short-term versus long-term consequences of smoking and vaping as predictors of non-use in a 3-year nationally representative survey study of US youth

INTRODUCTION

Efforts to prevent youth tobacco use are critical to reducing smoking-related deaths in the USA. Anti-tobacco messaging often focuses on the severe long-term consequences of smoking (eg, fatal lung disease, cancer). It is unclear whether these long-term consequences are more likely to deter youth use than shorter term consequences (eg, headaches, friend disapproval).

METHODS

A nationally representative 3-year rolling survey of adolescents and young adults (ages 13-26 years) measured belief in potential consequences of two types of tobacco products: combustible cigarettes (n=11 847) and electronic cigarettes (n=4470) as well as intentions and current use. Independent coders classified 23 consequences as either short or long term. Logistic regression tested the associations between short-term (vs long-term) beliefs and current intentions, as well as non-smoking behaviour at 6-month follow-up.

RESULTS

Believing in both short-term and long-term consequences was associated with outcomes, but short-term beliefs were more highly associated with anti-smoking (OR=1.40, 95% CI (1.30 to 1.51)) and anti-vaping (OR=2.10, 95% CI (1.75 to 2.52)) intentions and better predicted non-smoking behaviour at follow-up, controlling for prior use (OR=1.75, 95% CI (1.33 to 2.31)).

CONCLUSIONS

These results support temporal discounting by adolescents and young adults and suggest health communication efforts aiming to reduce youth tobacco use should emphasise shorter term consequences.

Atherosclerosis inflammation and burden in young adult smokers and vapers measured by PET/MR

BACKGROUND AND AIMS

Electronic cigarette (EC) use is popular among youth, touted as a safer alternative to smoking and promoted as a tool to aid in smoking cessation. EC cardiovascular safety however is not well established. The aim of this study was to examine cardiovascular consequences of EC use by evaluating their effect on the entire atherosclerotic cascade in young adults using noninvasive combined positron emission tomography (PET)/magnetic resonance imaging (MR) and comparing EC use with age matched smokers of traditional cigarettes and nonsmoking controls.

METHODS

Carotid PET/MR was applied to look at vascular inflammation (18-fluorodeoxyglucose (FDG)-PET) and plaque burden (multi-contrast MR of vessel wall) from 60 18-30 year-old subjects (20 electronic cigarette users, 20 traditional smokers and 20 nonsmokers).

RESULTS

Groups were reasonably well balanced in terms of age, gender, demographics, cardiovascular risk and most biomarkers. There were no differences in vascular inflammation as measured by 18-FDG-PET target to background ratios (TBR) between EC users, traditional cigarette smokers and nonsmokers. However, measures of carotid plaque burden - wall area, normalized wall index, and wall thickness - measured from MR were significantly higher in both traditional smokers and EC users than in nonsmokers.

CONCLUSIONS

Young adult EC users, smokers and nonsmokers in our study did not exhibit vascular inflammation as defined by 18-F-FDG-PET TBR max, but smokers and EC users had significantly more carotid plaque burden compared to matched nonsmokers. Results could indicate that vaping does not cause an increase in vascular inflammation as measured by FDG-PET.