Electronic cigarette use intensity measurement challenges and regulatory implications

Psychometric properties of measures for electronic cigarette dependence among former-smoking electronic cigarette users

BACKGROUND

Measures designed to assess electronic cigarette (ECIG) dependence are largely adapted from those developed for cigarette smoking, and have been evaluated mainly among dual ECIG-cigarette users. The present study evaluated the psychometric properties of four dependence measures among former-smoking ECIG users.

METHODS

Respondents (N = 187) were daily ECIG users who had formerly smoked cigarettes regularly. As part of an online survey, they completed four dependence measures: Penn State Electronic Cigarette Dependence Index (PSECDI); E-Cigarette Dependence Scale (EDS-4); Glover Nilsson Behavioral Questionnaire (GNBQ); and Diagnostic and Statistical Manual 5th Edition (DSM-5).

RESULTS

Confirmatory factor analysis revealed a single factor structure for all four measures, and fit indices were adequate for all models. Most inter-item correlations (mean r's = 0.21 to 0.45) and all item-total correlations (mean r's = 0.53 to 0.80) were significant for all four measures. Internal consistency was highest for the GNBQ (α = 0.86) followed by the EDS-4 (α = 0.81), PSECDI (α = 0.76), and DSM-5 (α = 0.75). Age of ECIG initiation was correlated negatively with scores on the EDS-4 and DSM-5, while number of ECIG quit attempts was correlated positively with scores on all measures except the GNBQ. Convergent validity was highest for comparisons between the EDS-4 and PSECDI (r = 0.75) though all comparisons were significant (p's < 0.001).

CONCLUSIONS

All four measures demonstrated acceptable reliability and validity in this sample of former-smoking ECIG users.

A tipping point in dihydroxyacetone exposure: mitochondrial stress and metabolic reprogramming alter survival in rat cardiomyocytes H9c2 cells

Exogenous exposures to the triose sugar dihydroxyacetone (DHA) occur from sunless tanning products and electronic cigarette aerosol. Once inhaled or absorbed, DHA enters cells, is converted to dihydroxyacetone phosphate (DHAP), and incorporated into several metabolic pathways. Cytotoxic effects of DHA vary across the cell types depending on the metabolic needs of the cells, and differences in the generation of reactive oxygen species (ROS), cell cycle arrest, and mitochondrial dysfunction have been reported. We have shown that cytotoxic doses of DHA induced metabolic imbalances in glycolysis and oxidative phosphorylation in liver and kidney cell models. Here, we examine the dose-dependent effects of DHA on the rat cardiomyocyte cell line, H9c2. Cells begin to experience cytotoxic effects at low millimolar doses, but an increase in cell survival was observed at 2 mM DHA. We confirmed that 2 mM DHA increased cell survival compared to the low cytotoxic 1 mM dose and investigated the metabolic differences between these two low DHA doses. Exposure to 1 mM DHA showed changes in the cell's fuel utilization, mitochondrial reactive oxygen species (ROS), and transient changes in the glycolysis and mitochondrial energetics, which normalized 24 h after exposure. The 2 mM dose induced robust changes in mitochondrial flux through acetyl CoA and elevated expression of fatty acid synthase. Distinct from the 1 mM dose, the 2 mM exposure increased mitochondrial ROS and NAD(P)H levels, and sustained changes in LDHA/LDHB and acetyl CoA-associated enzymes were observed. Although the cells were exposed to low cytotoxic (1 mM) and non-cytotoxic (2 mM) acute doses of DHA, significant changes in mitochondrial metabolic pathways occurred. Further, the proliferation increase at the acute 2 mM DHA dose suggests a metabolic adaption occurred with sustained consequences in survival and proliferation. With increased exogenous exposure to DHA through e-cigarette aerosol, this work suggests cell metabolic changes induced by acute or potentially chronic exposures could impact cell function and survival.

Comparison of emissions across tobacco products: A slippery slope in tobacco control

In this narrative review, we highlight the challenges of comparing emissions from different tobacco products under controlled laboratory settings (using smoking/vaping machines). We focus on tobacco products that generate inhalable smoke or aerosol, such as cigarettes, cigars, hookah, electronic cigarettes, and heated tobacco products. We discuss challenges associated with sample generation including variability of smoking/vaping machines, lack of standardized adaptors that connect smoking/vaping machines to different tobacco products, puffing protocols that are not representative of actual use, and sample generation session length (minutes or number of puffs) that depends on product characteristics. We also discuss the challenges of physically characterizing and trapping emissions from products with different aerosol characteristics. Challenges to analytical method development are also covered, highlighting matrix effects, order of magnitude differences in analyte levels, and the necessity of tailored quality control/quality assurance measures. The review highlights two approaches in selecting emissions to monitor across products, one focusing on toxicants that were detected and quantified with optimized methods for combustible cigarettes, and the other looking for product-specific toxicants using non-targeted analysis. The challenges of data reporting and statistical analysis that allow meaningful comparison across products are also discussed. We end the review by highlighting that even if the technical challenges are overcome, emission comparison may obscure the absolute exposure from novel products if we only focus on relative exposure compared to combustible products.

Reactions to a Hypothetical Ban of Open-System Electronic Cigarettes Among People Who Currently Use Electronic Cigarettes

INTRODUCTION

Policies limiting electronic cigarette (ECIG) device and liquid characteristics have been considered to prevent dependence potential and youth product appeal. "Open-system" ECIGs allow people to adjust device and liquid characteristics, which may undermine these policies. This study examined anticipated reactions to a policy prohibiting the sale of open-system ECIG devices in the United States using concept mapping.

METHODS

In 2020, adults who reported ECIG use in the past 30 days (n = 70; 45.1% women; mean age = 33.0, SD = 10.6) recruited from a research registry of individuals from across the United States provided statements into a shared list that completed a prompt: "If open-system vaping devices were no longer sold in the US and only closed-system vaping devices were available, what is a specific reaction or response you would have?" at a study website. Participants rated statements (1-7) on how true the statements were for them. Multidimensional scaling and hierarchical cluster analyses were used to identify thematic clusters. Mean ratings of statements were calculated and compared based on the type of ECIG used and current cigarette smoking status.

RESULTS

Participants generated 85 unique statements. The analysis identified eight themes that were organized into two broad groups. The first group of five clusters described behavioral responses to the hypothetical policy (Loopholes, Switch to Closed-System ECIGs, Legal Approaches to Use Open-System ECIGs, ECIG Use Cessation, Switch to non-ECIG Products). The second group of three clusters described psychological responses to the hypothetical policy (Closed-System ECIG Cons, Psychological Responses, Policy Outcome Concerns).

CONCLUSIONS

While a ban on open-system ECIG devices may have positive impacts on public health, policy loopholes, and consumer behaviors may undermine the policy. Efforts to support policy enforcement could increase policy effectiveness.

IMPLICATIONS

Open-system electronic cigarettes (ECIGs) that allow people who use ECIGs to modify ECIG device and liquid characteristics may limit the effectiveness of policies that establish product standards which attempt to limit nicotine delivery and flavor content in ECIG liquids. This study identified predicted reactions to a hypothetical policy prohibiting the sale of open-system ECIGs in the United States. Results suggest that people who use ECIGs may view a policy prohibiting open-system ECIGs unfavorably, but would be willing to use closed-system ECIGs. However, many ECIG users may attempt to find loopholes in the policy or alternative sources to purchase open-system ECIGs if open-systems were banned. Future research should identify strategies for tobacco regulatory policy enforcement to increase effectiveness.

Nicotine dependence among undergraduates who use nicotine salt-based e-cigarettes

OBJECTIVE

This study examined the relationship between use patterns of a popular e-cigarette brand using nicotine salts, JUUL, and symptoms of nicotine dependence in a college cohort.

PARTICIPANTS

Data for this study came from a prospective cohort of undergraduate students at a large Midwestern university from 2018 to 2019.

METHODS

Among participants who had ever tried a JUUL (N = 411), univariate and multivariable logistic regression were used to test the associations between use frequency (past 30-day use) and quantity (time to finish a pod) and nicotine dependence at follow up.

RESULTS

In the multivariable models, both frequency of use and quantity of use were associated with subsequent nicotine dependence, based on most indicators of dependence.

CONCLUSIONS

As salt-based nicotine is now present in the most popular e-cigarette brands used by young people, such findings inform our contemporary understanding of e-cigarettes' addictive potential and can help inform campus-based interventions.

Recency of Cannabis Vaping in Sexual Minorities in Wave 5 of the Population Assessment of Tobacco and Health (PATH) Study

BACKGROUND

Cannabis vaping is increasing in the United States. Among populations at-risk are sexual minorities (SM) who are more likely to vape cannabis compared to their heterosexual counterparts. Cannabis vaping has been associated with negative health outcomes and concomitant use of other substances with increased risk with more recent use.

OBJECTIVES

This study examined the association between SM identification and recency of cannabis vaping (the last occasion that a participant used their vape device with cannabis) and number of puffs (the count of puffs that the participant took during their most recent use of their vape device with cannabis) using Wave 5 of the Population Assessment of Tobacco and Health (PATH) Study.

RESULTS

In a weighted sample of participants who reported ever vaping cannabis (N = 5,331), 15% identified as SM, about 60% vaped cannabis in the past 3 or more days, and the mean number of puffs was 2 (SE = 0.17). Using multinomial logistic regression and zero-inflated negative binomial regression, the results showed that compared to heterosexual adults who reported not recently vaping cannabis, SM had higher probabilities of vaping cannabis in the past 3 or more days, 1-2 days, and the day of interview.

CONCLUSION

SM individuals were more likely to recently vape cannabis, placing them at higher risk for respiratory diseases and use of other substances. Public health researchers and practitioners need to identify reasons for cannabis vaping in this population and implement targeted public health messaging to inform SM communities of the potential health effects of cannabis vaping.

Factors associated with Korean adolescent's e-cigarette use by the severity level of generalized anxiety disorder (GAD-7)

BACKGROUND

The use of e-cigarette among Korean adolescents is spreading with alarming rapidity, but it has not been studied along with the severity level of GAD-7. This study aims to identify adolescents' e-cigarette use and its associated factors among four different anxiety groups using the problem behavioral theory (PBT).

METHODS

A cross-sectional secondary dataset was retrieved from the 2020 Korea Youth Risk Behavior Survey. Of the total sample of 54,948, four anxiety groups were formed: minimal (score 0-4; n = 36,711), mild (score 5-9; n = 12,138), moderate (score 10-14; n = 4143), and severe (score above 15; n = 1965). A total of 11 variables were selected based on the PBT domains. Descriptive analysis, Chi-square, ANOVA, univariate analysis, and multiple linear regression analysis were performed.

RESULTS

E-cigarette use was the highest in the order of severe, mild, moderate, and minimal. While cigarette use was associated with vaping in all anxiety groups, adolescents with minimal or mild anxiety levels were more likely to be influenced by tobacco accessibility and other behavior system factors such as sexual intercourse, alcohol use, and smartphone addiction. Meanwhile, secondhand smoke exposure in public areas was only associated with those with severe anxiety levels, and secondhand smoke exposure at school was a significant factor in all anxiety groups except for those with moderate anxiety levels.

LIMITATION

Due to the nature of cross-sectional dataset, the study could not draw causal links between vaping and other identified factors, include all the necessary PBT components.

CONCLUSION

These findings underscore the need to consider different levels of anxiety when addressing the problems related to vaping among Korean adolescents.

Decision Trade-Offs in Ecological Momentary Assessments and Digital Wearables Uptake: Protocol for a Discrete Choice Experiment

BACKGROUND

Ecological momentary assessments (EMAs) and digital wearables (DW) are commonly used remote monitoring technologies that capture real-time data in people's natural environments. Real-time data are core to personalized medical care and intensively adaptive health interventions. The utility of such personalized care is contingent on user uptake and continued use of EMA and DW. Consequently, it is critical to understand user preferences that may increase the uptake of EMA and DW.

OBJECTIVE

The study aims to quantify users' preferences of EMA and DW, examine variations in users' preferences across demographic and behavioral subgroups, and assess the association between users' preferences and intentions to use EMA and DW.

METHODS

We will administer 2 discrete choice experiments (DCEs) paired with self-report surveys on the internet to a total of 3260 US adults through Qualtrics. The first DCE will assess participants' EMA preferences using a choice-based conjoint design that will ask participants to compare the relative importance of prompt frequency, number of questions per prompt, prompt type, health topic, and assessment duration. The second DCE will measure participants' DW preferences using a maximum difference scaling design that will quantify the relative importance of device characteristics, effort expectancy, social influence, and facilitating technical, health care, and market factors. Hierarchical Bayesian multinomial logistic regression models will be used to generate subject-specific preference utilities. Preference utilities will be compared across demographic (ie, sex, age, race, and ethnicity) and behavioral (ie, substance use, physical activity, dietary behavior, and sleep duration) subgroups. Regression models will determine whether specific utilities are associated with attitudes toward or intentions to use EMA and DW. Mixture models will determine the associations of attitudes toward and intentions to use EMA and DW with latent profiles of user preferences.

RESULTS

The institutional review board approved the study on December 19, 2022. Data collection started on January 20, 2023, and concluded on May 4, 2023. Data analysis is currently underway.

CONCLUSIONS

The study will provide evidence on users' preferences of EMA and DW features that can improve initial uptake and potentially continued use of these remote monitoring tools. The sample size and composition allow for subgroup analysis by demographics and health behaviors and will provide evidence on associations between users' preferences and intentions to uptake EMA and DW. Limitations include the cross-sectional nature of the study, which limits our ability to measure direct behavior. Rather, we capture behavioral intentions for EMA and DW uptake. The nonprobability sample limits the generalizability of the results and introduces self-selection bias related to the demographic and behavioral characteristics of participants who belong to web-based survey panels.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/47567.

Nicotine dependence and associated factors among persons who use electronic e-cigarettes in Malaysia - an online survey

BACKGROUND

Nicotine dependence, factors associated with dependence, and self-reported side effects among people who use e-cigarettes are scarce in developing countries.

METHODS

A sample of 302 persons who currently use e-cigarettes was recruited from discussion forums on Reddit, Facebook, and the forum 'lowyat'. The online Google form survey collected data on demographics, e-cigarette use, and the reasons, for cigarette smoking, Fagerstorm Test for Nicotine Dependence adapted for e-cigarettes (eFTND), and side effects experienced.

RESULTS

The mean age was 25.5 years (6.5), 60.6% were males and 86% had higher education. About 47% were using e-cigarettes only, 27.8% were currently using dual products (both electronic and conventional cigarettes), and 25.2% had also smoked cigarettes in the past. 'Less harmful than cigarettes' (56.3%), 'because I enjoy it' (46.7%), and 'it has a variety of flavors (40.4%) were the common reasons for e-cigarette use. The mean eFTND score was 3.9 (SD = 2.2), with a median of four side effects (IQR 3-6), sore or dry mouth/throat (41.4%), cough 33.4%, headache (20.5%), dizziness (16.2%) were commonly reported side effects. eFTND score and side effects were higher among persons using dual products. By multiple linear regression analysis, males (β = 0.56 95% CI 0.45, 1.05, p = 0.033), dual-use (β = 0.95 95% CI 0.34, 1.56, p < 0.003), and use of nicotine-containing e-cigarettes (β = 0.66 95% CI 0.07, 1.25 p = 0.024) had higher eFTND score.

CONCLUSION

Our findings of the study call for the placement of disclaimers about possible nicotine addiction and side effects of e-cigarette products.

Effectiveness of e-cigarettes as aids for smoking cessation: evidence from the PATH Study cohort, 2017-2019

OBJECTIVE

To assess the effectiveness of e-cigarettes in smoking cessation in the USA from 2017 to 2019, given the 2017 increase in high nicotine e-cigarette sales.

METHODS

In 2017, the PATH Cohort Study included data on 3578 previous year smokers with a recent quit attempt and 1323 recent former smokers. Respondents reported e-cigarettes or other products used to quit cigarettes and many covariates associated with e-cigarette use. Study outcomes were 12+ months of cigarette abstinence and tobacco abstinence in 2019. We report weighted unadjusted estimates and use propensity score matched analyses with 1500 bootstrap samples to estimate adjusted risk differences (aRD).

RESULTS

In 2017, 12.6% (95% CI 11.3% to 13.9%) of recent quit attempters used e-cigarettes to help with their quit attempt, a decline from previous years. Cigarette abstinence for e-cigarette users (9.9%, 95% CI 6.6% to 13.2%) was lower than for no product use (18.6%, 95% CI 16.0% to 21.2%), and the aRD for e-cigarettes versus pharmaceutical aids was -7.3% (95% CI -14.4 to -0.4) and for e-cigarettes versus any other method was -7.7% (95% CI -12.2 to -3.2). Only 2.2% (95% CI 0.0% to 4.4%) of recent former smokers switched to a high nicotine e-cigarette. Subjects who switched to e-cigarettes appeared to have a higher relapse rate than those who did not switch to e-cigarettes or other tobacco, although the difference was not statistically significant.

CONCLUSIONS

Sales increases in high nicotine e-cigarettes in 2017 did not translate to more smokers using these e-cigarettes to quit smoking. On average, using e-cigarettes for cessation in 2017 did not improve successful quitting or prevent relapse.

Electronic Cigarette Users' Reactions and Responses to a Hypothetical Nicotine Concentration Reduction in Electronic Cigarette Liquids

Background: Regulations limiting nicotine in electronic cigarettes (e-cigarettes) have been proposed or implemented. Little is known about e-cigarette users' reactions to reducing e-cigarette liquid nicotine concentration. Methods: We used concept mapping to describe e-cigarette users' reactions to a 50% reduction in the nicotine concentration of their e-cigarette liquids. In 2019, current e-cigarette users who used e-cigarette liquid with greater than 0 mg/ml nicotine concentration completed an online study. Participants (n = 71, mean age = 34.9 (SD = 11.0), 50.7% women), brainstormed statements completing a prompt: "If the e-liquid that I use now in my e-cigarette/vaping device was only available in half the nicotine concentration or amount that I use now, a specific action I would take or a specific reaction I would have is…", Participants then sorted a final list of 67 statements into piles of similar content and rated statements on how true the statements would be for them. Multidimensional scaling and hierarchical cluster analyses identified thematic clusters. Results: Eight clusters were identified: (1) Replacement Product Seeking, (2) Mental Preparations and Expectations, (3) Use the New Liquid, (4) Information Seeking, (5) Compensation Behaviors, (6) Opportunity for E-Cigarette Reduction, (7) Physical and Psychological Effects, and (8) Replacement with non-E-Cigarette Products and Behaviors. Cluster ratings suggested many participants would search for other e-cigarette products/liquids to replace their current liquids, but using other tobacco products (e.g., cigarettes) may be less likely. Conclusions: If nicotine concentrations were decreased in e-cigarette liquids, e-cigarette users may attempt to purchase different e-cigarette products or modify their products to achieve desired effects.

Vaping Dose, Device Type, and E-Liquid Flavor are Determinants of DNA Damage in Electronic Cigarette Users

INTRODUCTION

Despite the widespread use of electronic cigarettes, the long-term health consequences of vaping are largely unknown.

AIMS AND METHODS

We investigated the DNA-damaging effects of vaping as compared to smoking in healthy adults, including "exclusive" vapers (never smokers), cigarette smokers only, and nonusers, matched for age, gender, and race (N = 72). Following biochemical verification of vaping or smoking status, we quantified DNA damage in oral epithelial cells of our study subjects, using a long-amplicon quantitative polymerase chain reaction assay.

RESULTS

We detected significantly increased levels of DNA damage in both vapers and smokers as compared to nonusers (p = .005 and p = .020, respectively). While the mean levels of DNA damage did not differ significantly between vapers and smokers (p = .522), damage levels increased dose-dependently, from light users to heavy users, in both vapers and smokers as compared to nonusers. Among vapers, pod users followed by mod users, and those who used sweet-, mint or menthol-, and fruit-flavored e-liquids, respectively, showed the highest levels of DNA damage. The nicotine content of e-liquid was not a predictor of DNA damage in vapers.

CONCLUSIONS

This is the first demonstration of a dose-dependent formation of DNA damage in vapers who had never smoked cigarettes. Our data support a role for product characteristics, specifically device type and e-liquid flavor, in the induction of DNA damage in vapers. Given the popularity of pod and mod devices and the preferability of sweet-, mint or menthol-, and fruit-flavored e-liquids by both adult- and youth vapers, our findings can have significant implications for public health and tobacco products regulation.

IMPLICATIONS

We demonstrate a dose-dependent formation of DNA damage in oral cells from vapers who had never smoked tobacco cigarettes as well as exclusive cigarette smokers. Device type and e-liquid flavor determine the extent of DNA damage detected in vapers. Users of pod devices followed by mod users, and those who use sweet-, mint or menthol-, and fruit-flavored e-liquids, respectively, show the highest levels of DNA damage when compared to nonusers. Given the popularity of pod and mod devices and the preferability of these same flavors of e-liquid by both adult- and youth vapers, our findings can have significant implications for public health and tobacco products regulation.

Electronic Nicotine Delivery Systems and Cardiovascular/Cardiometabolic Health

The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing these devices is now predominantly adolescents that are not trying to quit the use of traditional combustible cigarettes, but rather are new users. The composition and appearance of these devices has changed since their first entry into the market in the late 2000s, but they remain composed of a battery and aerosol delivery system that is used to deliver breakdown products of propylene glycol/vegetable glycerin, flavorings, and potentially nicotine or other additives. Manufacturers have also adjusted the type of nicotine that is used within the liquid to make the inhalation more palatable for younger users, further affecting the number of youth who use these devices. Although the full spectrum of cardiovascular and cardiometabolic consequences of e-cig use is not fully appreciated, data is beginning to show that e-cigs can cause both short- and long-term issues on cardiac function, vascular integrity and cardiometabolic issues. This review will provide an overview of the cardiovascular, cardiometabolic, and vascular implications of the use of e-cigs, and the potential short- and long-term health effects. A robust understanding of these effects is important in order to inform policy makers on the dangers of e-cigs use.

"I'm both smoking and vaping": a longitudinal qualitative study of US young adults who tried to quit smoking cigarettes by using electronic cigarettes

OBJECTIVE

To describe how young adults use electronic cigarettes (electronic nicotine delivery systems (ENDS)) for smoking cessation and reasons why they may or may not successfully quit smoking.

METHODS

Longitudinal qualitative data were collected annually from 2017 to 2019 for 25 young adult tobacco users (aged 18-29 years) in California (USA) who used ENDS to quit/reduce smoking. Thematic and trajectory analyses were used to identify key within-person and between-person changes in tobacco/nicotine use over time.

RESULTS

Five types of tobacco use transition were identified among baseline dual users of cigarettes and ENDS: sustained dual use without reduced smoking (n=8), transition to exclusive daily ENDS use (n=6), sustained dual use with reduced smoking (n=5), transition back to exclusive smoking (n=4) and transition to neither smoking nor vaping (n=2). Participants' ENDS use behaviour varied over time in terms of vaping quantity and device characteristics (eg, changing nicotine concentrations/flavours, switching between multiple devices). Three themes that related to successfully replacing cigarettes with ENDS were perceived positive physical effects, perceived satisfaction and enjoyment and context changes. Four themes for unsuccessful replacement were perceived negative physical discomforts, perceived addictiveness and harm, unsatisfactory substitution for cigarettes and device malfunction.

CONCLUSIONS

Young adults' experiences with using ENDS as a smoking cessation aid were highly variable. Adequate nicotine delivery and perceived safety and benefits contributed to successfully reducing or quitting cigarettes. Providing behavioural counselling and standardising ENDS products may enhance cessation for young adults.

Actual Use Behavior Assessment of a Novel Puff Recording Electronic Nicotine Delivery System: Observation Study

BACKGROUND

Compared with combustible cigarettes, electronic cigarettes (e-cigarettes) can deliver a sufficient amount of nicotine with a significantly reduced emission of toxicants, which renders them as potential harm reduction candidates for tobacco and smoking replacement. However, the use of e-cigarettes is not harm free and the long-term health effect of using e-cigarettes is yet to be established. Given the high prevalence of e-cigarette use across the globe and its potential health concerns, it is imperative to conduct actual use behavior assessments to better understand how e-cigarettes are being consumed in real-world conditions. However, with the currently available technologies, there is still a lack of noninvasive, noninterventional, and convenient instruments for the real-time and real-world use behavior monitoring of e-cigarette product use. Novel technology-based systems that do not primarily rely on self-report or intrusive measurements to monitor e-cigarette use behaviors are therefore highly desired.

OBJECTIVE

The primary goal of this study is to investigate the e-cigarette actual use behaviors in the real world via a novel puff recording electronic nicotine delivery system (PR-ENDS). Specifically, we aim to analyze and summarize the survey and PR-ENDS use data and to study the relationships and effects of different factors on these variables.

METHODS

In real-world conditions, 61 enrolled UK e-cigarette users were instructed to use PR-ENDS as the primary source of nicotine with their selected e-liquids for at least 3 weeks (21 days). A baseline survey was conducted to collect information about participants' demographics and nicotine use history (cigarette and ENDS). The puff data (ie, puff number, puff duration for each puff, device power, e-liquid nicotine concentrations) were directly recorded by PR-ENDS and uploaded to the cloud for further analyses. The nicotine emission and nicotine consumption were estimated based on recorded puff data.

RESULTS

Middle-aged adults with a nicotine history represented the major user profile during the PR-ENDS trial. A wide range of device power and e-liquid nicotine concentrations was applied and their combinations during actual use were found to be rather complex. Various puff parameters (ie, puff duration, puff number, nicotine emission) were assessed with contributing factors from device, e-liquid, and user nicotine history in different effect sizes. The real-time observation revealed substantial intra- and interindividual variabilities in PR-ENDS use behaviors. The use pattern of a quick adaptation followed by consistent product use was recognized for at least 3 weeks during actual use.

CONCLUSIONS

The actual use behavior assessment of PR-ENDS was conducted as a proof-of-concept application. The complex interactions of product attributes and significant intra- and interindividual variabilities in e-cigarette use behaviors provided new insights of compensatory behavior, which can inspire future studies in the field of nicotine addiction and abuse liability behavior assessment.

E-Cigarette Users' Profiles and Their Association with Identified Impacts of COVID-19 on Vaping among Young Adults in Malaysia

Electronic cigarettes (ECs) users' profiles and behaviors during the COVID-19 pandemic remain unclear. This cross-sectional study aimed to explore Malaysian EC users' profiles and their associations with related behaviors during the pandemic. The EC users (N = 351) were recruited from an official national vape entity. Respondents were predominantly of Malay ethnicity (90.6%), aged 31 to 35 years (27.6%), males (97.7%), married (68.7%), from Malaysia's west region states (63.5%) and tertiary educated (69.2%). The majority (80.3%) were non-dual users, and most purchased their vaping products online (77.2%), liked that they can vape while working at home (83.8%) and vaped more because of boredom (55.3%), had low and moderate nicotine addiction levels (94.9%), had low motivation level to quit EC use (92.6%) and were more likely to perceive that vaping did not increase the chances of complications from COVID-19. Respondents with moderate to high addiction levels had twice the odds of checking on their current EC supplies, whilst respondents with low motivation to quit had higher odds of using their tank/pod until the last drop and distancing from others when vaping. EC users should be encouraged to quit EC use, especially during the COVID-19 pandemic.

Effects of tobacco product use on oral health and the role of oral healthcare providers in cessation: A narrative review

Tobacco use has detrimental effects on health, including oral health. The emergence and increasing popularity of newer tobacco and nicotine products make tobacco use one of the major public health problems in the world. Tobacco use increases the risk of oral diseases such as oral cancer, oral mucosal lesions, periodontal disease, and dental caries, among many other oral diseases and conditions. The dental office is an excellent venue for providing cessation intervention. However, there is a lack of knowledge and training in tobacco use prevention among dental professionals. More efforts are needed for smoking cessation interventions in the dental office. Smoking cessation interventions provided by oral healthcare providers include brief educational, behavioral, and pharmacological interventions. This review provides an overview of the ill effects of tobacco use on oral health and the role of oral healthcare providers in managing and preventing tobacco dependence.

The Health Effects of Real-World Dual Use of Electronic and Conventional Cigarettes versus the Health Effects of Exclusive Smoking of Conventional Cigarettes: A Systematic Review

BACKGROUND

A high prevalence of dual use of e-cigarettes and conventional cigarettes has been reported across the world.

METHODS

A systematic search was carried out. We included original articles on any topic relevant to health, excluding mental health, in all languages. The PRISMA guidelines were followed. Both reviewers independently screened and read all publications. We compared dual use with exclusive smoking of conventional cigarettes (ESCC).

RESULTS

Fifty-two publications (49 studies) were included. Thirteen papers/10 studies were prospective. There was great heterogeneity across studies. Many methodological weaknesses, such as inaccurate exposure measurement, lack of adjustment for former tobacco consumption, and lack of significance testing were identified. Most prospective studies found dual use to be at least as harmful as ESCC. The longest follow-up was six years. Most of the best available cross-sectional studies found dual use associated with the same and, in several studies, significantly higher risk of self-reported symptoms/disease than in ESCC. The intensity of cigarette smoking seems associated with worse health.

CONCLUSION

Existing studies indicate that dual use is at least as, or probably even more, harmful than ESCC. Due to the predominance of cross-sectional studies and the methodological weaknesses we judged the overall certainty of the evidence as "low certainty".

Validation of a High Flow Rate Puff Topography System Designed for Measurement of Sub-Ohm, Third Generation Electronic Nicotine Delivery Systems

There are few known puff topography devices designed solely for gathering electronic cigarette puff topography information, and none made for high-powered sub-ohm devices. Ten replicate Bernoulli flow cells were designed and 3D printed. The relationship between square root of pressure difference and flow rate was determined across 0−70 L/min. One representative flow cell was used to estimate puff volume and flow rate under six simulated puffing regimes (0.710 L, 2.000 L and 3.000 L, at low and high flow rates) to determine the system’s accuracy and utility of using dual pressure sensors for flow measurement. The relationship between flow rate and square root of pressure differential for the ten replicate cells was best fit with a quadratic model (R2 = 0.9991, p < 0.0001). The higher-pressure sensor was accurate at both low and high flow rates for 0.71 L (102% and 111% respectively), 2.00 L (96% and 103% respectively), and 3.00 L (100.1% and 107% respectively) but the lower-pressure sensor provided no utility, underpredicting volume and flow. This puff topography system generates very little resistance to flow, easily fits between user’s atomizer and mouthpiece, and is calibrated to measure flows up to 70 L/min.

Association of Electronic Cigarette Use with Respiratory Symptom Development among U.S. Young Adults

Rationale: Electronic cigarette (e-cigarette) use is highly prevalent among young adults. However, longitudinal data assessing the association between e-cigarette use and respiratory symptoms are lacking. Objectives: To determine whether e-cigarette use is associated with the development of respiratory symptoms in young adults. Methods: Data are derived from the PATH (Population Assessment of Tobacco and Health) study waves 2 (2014-2015), 3 (2015-2016), 4 (2016-2018), and 5 (2018-2019). Young adults aged 18-24 years at baseline with no prevalent respiratory disease or symptoms were included in the analyses. Binary logistic regression models with a generalized estimating equation were used to estimate time-varying and time-lagged associations of e-cigarette use during waves 2-4, with respiratory symptom development approximately 12 months later at waves 3-5. Measurements and Main Results: The per-wave prevalence of former and current e-cigarette use was 15.2% and 5.6%, respectively. Former e-cigarette use was associated with higher odds of developing any respiratory symptom (adjusted odds ratio [aOR], 1.20; 95% confidence interval [CI], 1.04-1.39) and wheezing in the chest (aOR, 1.41; 95% CI, 1.08-1.83) in multivariable adjusted models. Current e-cigarette use was associated with higher odds for any respiratory symptom (aOR, 1.32; 95% CI, 1.06-1.65) and wheezing in the chest (aOR, 1.51; 95% CI, 1.06-2.14). Associations persisted among participants who never smoked combustible cigarettes. Conclusions: In this nationally representative cohort of young adults, former and current e-cigarette use was associated with higher odds of developing wheezing-related respiratory symptoms, after accounting for cigarette smoking and other combustible tobacco product use.