Adults' E-Cigarette Flavor Use and Cigarette Quit Attempts: Population Assessment of Tobacco and Health Study Findings

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

Background

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

Methods

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

Results

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

Conclusion

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

Adolescent and Young Adult Response to Hypothetical E-Liquid Flavor Restrictions

OBJECTIVE

Rates of e-cigarette use among adolescents and young adults (AYAs) remain high despite several federal policy changes intended to limit their availability and appeal. The current study examined how restricting flavors would affect current AYA users' intentions to discontinue vaping, as a function of their current flavor preference.

METHOD

In a national cross-sectional survey, AYA e-cigarette users (N = 1,414) completed measures of e-cigarette use, device type, e-liquid flavor (tobacco, menthol, cool mint, fruit ice, fruit/sweet), and intent to discontinue e-cigarette use in response to hypothetical federal product standards (i.e., tobacco and menthol or tobacco-only e-liquid). Logistic regression was used to model the association of preferred flavor with odds of discontinuing e-cigarette use (vs. continuing), for menthol and tobacco hypothetical product standards.

RESULTS

Overall, 38.8% of the sample reported intent to discontinue using their e-cigarette if tobacco and menthol-flavored e-liquid were the only options available, whereas 70.8% would discontinue under a tobacco-only product standard. AYAs preferring fruit/sweet flavor were most sensitive to either restricted scenario, with odds of discontinuing use ranging from adjusted odds ratio (aOR) = 2.22 to aOR = 2.38 under a tobacco and menthol product standard and aOR = 1.33 to aOR = 2.59 under a tobacco-only product standard, compared with other flavor preferences. In addition, AYAs using cooling flavors (e.g., fruit ice) reported higher odds of discontinuing use under a tobacco-only product standard, compared with menthol flavor users, indicating an important distinction between these groups.

CONCLUSIONS

Results indicate potential for flavor restrictions to reduce use of e-cigarettes among AYAs and suggest that a tobacco flavor product standard may result in the greatest discontinuation of use.

Investigating the effect of e-cigarette use on quitting smoking in adults aged 25 years or more using the PATH study

Background: The evidence on harms and benefits of e-cigarettes partly concerns whether their use encourages smokers to quit.  We addressed this using data from the nationally representative PATH study, with detailed accounting for potential confounding variables.

Methods: We considered adults aged 25+.  Our original analyses, reported in version 1 of this paper, used data for Waves 1 to 3, separate analyses considering Waves 1 to 2, 2 to 3 and 1 to 3.  These related baseline ever e-cigarette use (or e-product use at Wave 2) to quitting at follow-up, adjusting for confounders derived from 55 candidates.  Sensitivity analyses omitted ever other product users, linked quitting to current e-cigarette use, and used values of some predictors modified using follow-up data.  Additional analyses used data for Waves 1 to 4, separately considering sustained, delayed and temporary quitting during Waves 1 to 3, 2 to 4 and 1 to 4.  Sensitivity analyses considered 30-day quitting, restricted attention to smokers attempting to quit, and considered ever smokeless tobacco or snus use.

Results: In the original analyses, unadjusted odds ratios (ORs) of quitting smoking for ever e-cigarette use were 1.29 (95% CI 1.01-1.66), 1.52 (1.26-1.83) and 1.47 (1.19-1.82) for the Wave 1 to 2, 2 to 3, and 1 to 3 analyses.  These reduced after adjustment, to 1.23 (0.94-1.61), 1.51 (1.24-1.85) and 1.39 (1.11-1.74).  Quitting rates remained elevated in users in all sensitivity analyses.  The additional analyses found associations of e-cigarette use with sustained, delayed and temporary quitting, associations little affected by considering 30-day quitting, and only slightly reduced restricting attention to quit attempters.  Ever use of smokeless tobacco or snus also predicted increased quitting.  

Conclusions: As does most evidence from clinical trials, other analyses of PATH, and other epidemiological studies, our results suggest using e-cigarettes helps adult smokers to quit.

Responses to potential nicotine vaping product flavor restrictions among regular vapers using non-tobacco flavors: Findings from the 2020 ITC Smoking and Vaping Survey in Canada, England and the United States

INTRODUCTION

Some jurisdictions have implemented nicotine vaping product (NVP) flavor restrictions because of concerns about rising adolescent use. However, little is known how these restrictions may impact adult vapers. This study describes the level of support and predictive behavioral responses to a hypothetical NVP ban on non-tobacco flavors among regular adult vapers who only use flavors that would be banned.

METHODS

Data came from 851 regular vapers (all current or ex-smokers) participating in the 2020 ITC Four Country Smoking and Vaping Survey in Canada, England, and the United States (US). A random sample of respondents in each country received and completed the questions about flavor bans: (1) do you support or oppose a ban on all non-tobacco flavors; and (2) what would you do if all flavors were banned, with the exception of tobacco in the US, and tobacco and menthol in Canada and England. Those who used tobacco-flavored or unflavored NVPs were excluded from all analyses, and additionally, vapers of menthol flavor in Canada and England were excluded from Aim 2.

RESULTS

Overall, 53.6% of vapers were strongly opposed to flavor bans, 28.2% were opposed, 9.3% were in support, 3.6% were in strong support, and 5.2% did not know. Predicted behavioral responses were: 28.8% would continue vaping an available flavor, 28.3% would find a way to get their banned flavor(s), 17.1% would stop vaping and smoke instead, 12.9% said that they would stop vaping and not smoke, and 12.9% do not know what they would do. Responses to a potential flavor ban largely varied by smoking and vaping status, and by the level of support of a flavor restriction policy.

CONCLUSIONS

At this time, it is not clear what net population-level consequences would occur if non-tobacco flavored NVPs were prohibited. While a majority of vapers in this study opposed this policy, and many vapers would not be willing to switch to available flavors, there was considerable variability in predicted behavioral responses.

Nicotine content, labelling and flavours of e-liquids in Canada in 2020: a scan of the online retail market

INTRODUCTION

The e-cigarette market in Canada has rapidly evolved following the implementation of the Tobacco and Vaping Products Act in May 2018, which liberalized the promotion and sale of vaping products. To date, there is little data on the market profile of key product attributes, including nicotine content, labelling practices and flavours.

METHODS

An online scan of vaping product retailers (manufacturer, two national, five provincial) was conducted in 2020 to assess the e-liquids available on the Canadian market. Data were extracted from websites and product images regarding the nicotine content, labelling and flavours of e-liquids.

RESULTS

We identified 1746 e-liquids, with a total of 4790 different nicotine concentrations. Approximately half of the e-liquids were offered with salt-base nicotine (46.6%) and half with freebase nicotine (53.2%); the remainder were hybrids (0.2%). The mean nicotine concentration of salt-base e-liquids (3.4%) was higher than freebase e-liquids (0.5%) (p < 0.001). Labels indicating the presence of nicotine were visible on twothirds of e-liquid packaging displayed online (63.2%) while three-quarters of packaging displayed the nicotine concentration (73.7%), and more than half of packaging displayed health warnings (58.9%). A variety of flavours were also identified, with fruit being the most common (43.6%), followed by candy/desserts (27.6%) and non-alcoholic drinks (12.5%).

CONCLUSION

Findings demonstrate the diversity of the online e-cigarette market in Canada, including the availability of higher-concentration salt-base nicotine products. Flavour restrictions have the potential to dramatically reduce the number of e-liquid flavours on the market, while restricting nicotine concentrations to < 20 mg/mL will predominantly restrict salt-based e-liquids.

E-Cigarette Flavors and Frequency of E-Cigarette Use among Adult Dual Users Who Attempt to Quit Cigarette Smoking in the United States: Longitudinal Findings from the PATH Study 2015/16-2016/17

Potential mechanisms by which e-cigarette use may relate to combustible cigarette smoking cessation are not well-understood. We used U.S. nationally representative data to prospectively evaluate the relationship between e-cigarette flavor use and frequency of e-cigarette use among adult cigarette/e-cigarette dual users who attempted to quit smoking cigarettes. Analyses used Population Assessment of Tobacco and Health (PATH) Study data from adult dual users (2015/16) who attempted to quit smoking between 2015/16 and 2016/17 (Wave 3-Wave 4, n = 685, including those who did/did not quit by 2016/17). E-cigarette flavor use (usual/last flavor, past 30-day flavor; assessed in 2015/16) was categorized into Only tobacco; Only menthol/mint; Only non-tobacco, non-menthol/mint; and Any combination of tobacco, menthol/mint, other flavor(s). The key outcome, evaluated at follow-up in 2016/17, was frequent e-cigarette use, which was defined as use on 20+ of past 30 days. Logistic regression was used to evaluate associations between e-cigarette flavor use in 2015/16 and frequent e-cigarette use at follow-up in 2016/17. Dual users who attempted to quit smoking had greater odds of frequent e-cigarette use at follow-up when they used only non-tobacco, non-menthol/mint flavor than when they used only tobacco flavor as their regular/last e-cigarette flavor (OR = 1.9, 95% CI: 1.1-3.4); findings were no longer significant when adjusted for factors including e-cigarette device type (AOR = 1.4, 95% CI: 0.7-2.8). Past 30-day e-cigarette flavor use results were generally similar, although frequent e-cigarette use at follow-up was highest among those who used any combination of tobacco, menthol/mint, or other flavors. Findings indicate that e-cigarette flavor use among dual users who attempt to quit smoking may be related to e-cigarette use frequency overall, which may indicate a mechanism underlying findings for e-cigarette use and smoking cessation. Further longitudinal research may help to disentangle how e-cigarette characteristics uniquely impact e-cigarette use frequency and smoking cessation/sustained use.