Young adult e-cigarette use: A latent class analysis of device and flavor use, 2018-2019

Evaluating trends in recruitment challenges in vape shop research, e-cigarette product characteristics and use among shop customers from 2019 to 2023: A mixed-methods study

INTRODUCTION

Brick-and-mortar vape shops specialize in the sale of e-cigarettes and remain a primary source for purchasing emerging e-cigarette products. New regulatory policies have been implemented at local-, state- and federal-level; the retail environment at vape shops and product preferences among vape shop customers shifted accordingly.

METHODS

From 2019 to 2023, we collected anonymous interview data from vape shop customers (n=572) from 83 vape shops in Southern California. We aggregated the data by month and treated each month as the unit of analysis to document changes in recruitment efforts among the vape shops in relation to major policy implementations over 4 years. We also examined the systematic fluctuations and trends in customers' e-cigarette product preferences and nicotine content in these products.

RESULTS

The monthly average shop-level consent rate was 52.9% (SD=8.7), with an overall decreasing trend over time. It was necessary for our data collection team to approach a greater number of vape shops to obtain consent with implementation of various state and federal tobacco regulations and following COVID-19. We observed an increase in the purchase of disposable products and nicotine concentrations in the products, while the average use frequency remained the same.

CONCLUSIONS

Our findings demonstrated that user preferences, product characteristics and challenges in research involving vape shops are closely associated to changes in regulations. We documented a dramatic increase in nicotine concentration in products. Future policies restricting the amount of nicotine in tobacco products at the federal level are necessary to protect consumers from further nicotine addiction. This study provides documentation over time of the drastic increases in nicotine concentration among e-cigarette users as a result of the fluctuations in the product market. Regulating nicotine content in tobacco products could safeguard against further unsafe modifications in e-cigarettes and other types of tobacco products.

Relationship Between Product Features and the Prices of e-Cigarette Devices Sold in Web-Based Vape Shops: Comparison Study Using a Linear Regression Model

BACKGROUND

Open-system electronic cigarette (EC) product features, such as battery capacity, maximum output wattage, and so forth, are major components that drive product costs and may influence use patterns. Moreover, continued innovation and monitoring of product features and prices will provide critical information for designing appropriate taxation policies and product regulations.

OBJECTIVE

This study will examine how product features are associated with the prices of devices sold in web-based vape shops.

METHODS

We draw samples from 5 popular, US-based, web-based vape shops from April to August 2022 to examine starter kits, device-only products, and e-liquid container-only products. We implemented a linear regression model with a store-fixed effect to examine the association between device attributes and prices.

RESULTS

EC starter kits or devices vary significantly by type, with mod prices being much higher than pod and vape pen prices. The prices of mod starter kits were even lower than those of mod devices, suggesting that mod starter kits are discounted in web-based vape shops. The price of mod kits, mod device-only products, and pod kits increased as the battery capacity and output wattage increased. For vape pens, the price was positively associated with the volume size of the e-liquid container. On the other hand, the price of pod kits was positively associated with the number of containers.

CONCLUSIONS

A unit-based specific tax, therefore, will impose a higher tax burden on lower-priced devices such as vape pens or pod systems and a lower tax burden on mod devices. A volume- or capacity-based specific tax on devices will impose a higher tax burden on vape pens with a larger container size. Meanwhile, ad valorem taxes pegged to wholesale or retail prices would apply evenly across device types, meaning those with advanced features such as higher battery capacities and output wattage would face higher rates. Therefore, policy makers could manipulate tax rates by device type to discourage the use of certain device products.

Sex Differences in Electronic Cigarette Device Use Among College Students

Electronic cigarette use (vaping) has reached epidemic levels in the United States among teenagers and young adults. However, there is a paucity of studies that have examined the relationships between e-cigarette device types and user characteristics. Therefore, the main objective of this study was to characterize e-cigarette device use among a college population with a focus on sex differences in preferred vaping device. We employed a Qualtrics-based smartphone/online survey to gather responses on e-cigarette use; including device type, demographics and other related information during the period October 1, 2020 to January 30, 2022 in the Birmingham, AL metropolitan area. Participants were recruited via flyers with a QR code to the survey. The differences in e-cigarette device type used by the characteristics of the university e-cigarette users were assessed using either a Chi-square analysis or Fisher's Test. The magnitude of any association between the characteristics of the participants and vaping device used was analyzed via logistic regression. Out of 394 students who participated in the survey, 61 reported current exclusive e-cigarette use (15.5%) among our 18-24-year-old college student sample. Among vapers; more females reported use of Disposable e-cigarettes or Juul (pod-type) as their primary vaping device compared to males, who preferred Tanks and Mods + other rechargeable e-cigarettes (p < 0.05). Males also vaped more days per week compared to females. Vaping among young college students remains at concerning levels. The primary vaping device used significantly varies by the users' sex, making it an important factor to consider in future studies.

Chemical Flavorants in Vaping Products Alter Neurobiology in a Sex-Dependent Manner to Promote Vaping-Related Behaviors

Electronic nicotine delivery systems (ENDS) are distinctly different from combustible cigarettes because of the availability of flavor options. Subjective measures have been used to demonstrate that adults and adolescents prefer flavors for various reasons; (1) they are pleasing and (2) they mask the harshness of nicotine. Despite this, there have been few investigations into the molecular interactions that connect chemical flavorants to smoking or vaping-related behaviors. Here, we investigated the effects of three chemical flavorants (hexyl acetate, ethyl acetate, and methylbutyl acetate) that are found in green apple (GA) ENDS e-liquids but are also found in other flavor categories. We used a translationally relevant vapor self-administration mouse model and observed that adult male and female mice self-administered GA flavorants in the absence of nicotine. Using α4-mCherryα6-GFP nicotinic acetylcholine receptor (nAChR) mice, we observed that mice exposed to GA flavorants exhibited a sex-specific increase (upregulation) of nAChRs that was also brain-region specific. Electrophysiology revealed that mice exposed to GA flavorants exhibited enhanced firing of ventral tegmental area dopamine neurons. Fast-scan cyclic voltammetry revealed that electrically stimulated dopamine release in the nucleus accumbens core is increased in mice that are exposed to GA flavorants. These effects were similarly observed in the medial habenula. Overall, these findings demonstrate that ENDS flavors alone change neurobiology and may promote vaping-dependent behaviors in the absence of nicotine. Furthermore, the flavorant-induced changes in neurobiology parallel those caused by nicotine, which highlights the fact that nonmenthol flavorants may contribute to or enhance nicotine reward and reinforcement.SIGNIFICANCE STATEMENT The impact of flavors on vaping is a hotly debated topic; however, few investigations have examined this in a model that is relevant to vaping. Although a full understanding of the exact mechanism remains undetermined, our observations reveal that chemical flavorants in the absence of nicotine alter brain circuits relevant to vaping-related behavior. The fact that the flavorants investigated here exist in multiple flavor categories of vaping products highlights the fact that a multitude of flavored vaping products may pose a risk toward vaping-dependent behaviors even without the impact of nicotine. Furthermore, as the neurobiological changes have an impact on neurons of the reward system, there exists the possibility that nonmenthol flavorants may enhance nicotine reward and reinforcement.

Hypothetical flavour ban and intention to vape among vape shop customers: the role of flavour preference and e-cigarette dependence

INTRODUCTION

E-cigarette users typically initiate vaping with flavoured e-liquids. People who vape flavours tend to underestimate the harm of vaping. We examined the inter-relationship between flavour preference, vaping for cessation purposes, e-cigarette dependence, e-cigarette harm perception and purchase/use intention, given a hypothetical flavour ban. We hypothesised that non-tobacco flavour preference and vaping for cessation would be negatively associated with harm perception of e-cigarettes and intention to continue vaping if a flavour ban occurred and that these effects would be mediated by e-cigarette dependence.

METHODS

From July 2019 to March 2020, we conducted intercept interviews with 276 customers at 44 vape shops in California. The predictor variables were flavour preference and vaping for cessation. The outcome variables were harm perception of e-cigarettes and intention to purchase/use, given a hypothetical flavour ban. Multilevel structural equation modelling tested whether e-cigarette dependence mediates the effects of flavour preference on hypothetical continued vaping and purchase.

RESULTS

Those who preferred flavours showed significantly lower intention to purchase e-liquids (β=-0.28, p<0.001) and to continue vaping (β=-0.17, p=0.001), given a hypothetical flavour ban. Those who vaped for smoking cessation indicated greater intention to purchase e-liquid (β=0.10, p=0.016) and to continue vaping (β=0.17, p=0.001), given a hypothetical flavour ban. E-cigarette dependence significantly mediated these effects (ps<0.04).

DISCUSSION

Flavour preference was negatively related to intention to continue to vape within a hypothetical flavour ban. Our results also highlight the importance of e-cigarette dependence and use of e-cigarettes as smoking cessation methods. Implications for future flavour bans are discussed.

Electronic cigarette users' reactions and responses to a hypothetical ban of flavoured electronic cigarette liquids

Regulations have been proposed to limit e-cigarette flavours, but limited research has examined potential impacts of such policies. This study examined adult e-cigarette users’ reactions to a hypothetical e-cigarette flavour ban.

General and Device-Specific Reasons for ENDS Use: A Qualitative Study with Adult ENDS Users

BACKGROUND

A scientific consensus on the public health impact of electronic nicotine delivery systems (ENDS) remains elusive. This is partly due to the wide variation in product characteristics often lumped together under one category. Research is needed to better understand what ENDS device type characteristics motivate their use by adults.

METHODS

Nine focus groups of 32 current ENDS users who were 18+ years old, had used ENDS in the previous 30 days, and had been using ENDS for more than two months were held either in person or online between February and June 2020.

RESULTS

Participants' reasons for their choice of ENDS characteristics included both general, applying to all ENDS products, and specific, relating to particular ENDS devices. Health benefits and the lack of offensive odor were commonly identified as important reasons for using ENDS in general. Flavor and product discreteness were both general and device-specific determinants of ENDS use. Conversely, nicotine delivery, cloud size, battery properties, aesthetics, ease of use, and cost were device-specific drivers of participants' choice.

CONCLUSIONS

The reasons that adults choose to use ENDS are complex and sometimes related to both ENDS as a category and as specific ENDS product types. Regulations and public communication campaigns should reflect their ultimate objective and consider both general and specific motivations when attempting to achieve public health objectives.

Correlates of youth Poly-E-Cigarette device use

PURPOSE

The objective of this study was to examine poly-e-cigarette (poly-EC) device use among youth EC users and identify factors associated with poly- versus single-EC device use status.

METHODS

861 EC users aged 14-21 responded to an online survey about EC use and sociodemographic factors in August 2020. Respondents were included if they were current EC users (i.e., at least one day in the past 30 days) and excluded if they were currently using other tobacco products (OTPs).

RESULTS

Data analysis indicated poly-EC device use was associated with higher self-reported nicotine dependence, younger age of onset, having close friends who use ECs and higher or lower self-perceived socioeconomic status compared to others.

CONCLUSIONS

Young poly-EC device users were more likely to begin using at a younger age, live with and have close friends who were EC users, and report greater nicotine dependence. Identifying temporality in these associations can identify youth at greater risk of poly-EC use. Future research should examine poly-EC device use in prospective surveillance monitoring to further evaluate the longitudinal implications on use and dependence.

Preferences, use, and perceived access to flavored e-cigarettes among United States adolescents and young adults

Background:

Citing concern over youth use, the Food and Drug Administration announced a prioritized enforcement policy against cartridge-based (reusable pod) e-cigarettes in non-menthol, non-tobacco flavors, effective February 2020. Data are needed regarding youth e-cigarette access and use behaviors following this policy.

Methods:

This cross-sectional national (USA) online panel survey, conducted March/April 2021, included 2253 participants ages 14–20 who ever used e-cigarettes ≥3 times (73% past 30-day users). Participants reported their flavor preferences, use reasons, and perceived ease of access. Latent class analysis categorized participants according to their preferred e-cigarette flavors, and multinominal logistic regression identified sociodemographic and behavioral correlates of class membership.

Results:

Most past 30-day e-cigarette users used reusable pod (77%) or modern disposable (68%) devices, ≥1 non-tobacco (92%), sweet (76%), and/or menthol flavors including fruit-ice (70%) (flavor and device categories not mutually exclusive). Most past 30-day users (70%) and non-users (63%) perceived it would be somewhat or very easy to acquire e-cigarettes in flavors they like. Latent class analysis identified four e-cigarette flavor preference classes: mint (34% of sample), no preference (29%), fruit/sweet (28%), and dislikes ≥1 flavor (10%). Relative to no preference, membership in fruit/sweet (RRR: 1.87; 95% CI: 1.37, 2.57) and mint (RRR: 3.85; 95% CI: 2.77, 5.36) classes was associated with using e-cigarettes ≥50 times. Fruit/sweet membership was inversely associated with combustible tobacco use (RRR: 0.50; 95% CI: 0.38, 0.66).

Conclusion:

Young e-cigarette users maintained ample access to flavored and cartridge-based products. Stronger access restrictions and enforcement are required to reduce youth e-cigarette use.

Effect of Puffing Behavior on Particle Size Distributions and Respiratory Depositions From Pod-Style Electronic Cigarette, or Vaping, Products

The current fourth generation ("pod-style") electronic cigarette, or vaping, products (EVPs) heat a liquid ("e-liquid") contained in a reservoir ("pod") using a battery-powered coil to deliver aerosol into the lungs. A portion of inhaled EVP aerosol is estimated as exhaled, which can present a potential secondhand exposure risk to bystanders. The effects of modifiable factors using either a prefilled disposable or refillable pod-style EVPs on aerosol particle size distribution (PSD) and its respiratory deposition are poorly understood. In this study, the influence of up to six puff profiles (55-, 65-, and 75-ml puff volumes per 6.5 and 7.5 W EVP power settings) on PSD was evaluated using a popular pod-style EVP (JUUL® brand) and a cascade impactor. JUUL® brand EVPs were used to aerosolize the manufacturers' e-liquids in their disposable pods and laboratory prepared "reference e-liquid" (without flavorings or nicotine) in refillable pods. The modeled dosimetry and calculated aerosol mass median aerodynamic diameters (MMADs) were used to estimate regional respiratory deposition. From these results, exhaled fraction of EVP aerosols was calculated as a surrogate of the secondhand exposure potential. Overall, MMADs did not differ among puff profiles, except for 55- and 75-ml volumes at 7.5 W (p < 0.05). For the reference e-liquid, MMADs ranged from 1.02 to 1.23 μm and dosimetry calculations predicted that particles would deposit in the head region (36-41%), in the trachea-bronchial (TB) region (19-21%), and in the pulmonary region (40-43%). For commercial JUUL® e-liquids, MMADs ranged from 0.92 to 1.67 μm and modeling predicted that more particles would deposit in the head region (35-52%) and in the pulmonary region (30-42%). Overall, 30-40% of the particles aerosolized by a pod-style EVP were estimated to deposit in the pulmonary region and 50-70% of the inhaled EVP aerosols could be exhaled; the latter could present an inhalational hazard to bystanders in indoor occupational settings. More research is needed to understand the influence of other modifiable factors on PSD and exposure potential.