E-cigarettes for the management of nicotine addiction

Part one: abuse liability of Vuse Solo (G2) electronic nicotine delivery system relative to combustible cigarettes and nicotine gum

Abuse liability (AL) of electronic nicotine delivery systems (ENDS) is relevant as the category increases in popularity as a potentially less-harmful alternative to cigarette smoking. AL assessments are important to the FDA in determining if a new product is appropriate for the protection of public health. This paper reports the results for Vuse Solo (G2 cartridge design) compared to high and low AL-comparators evaluated in an open-label, randomized crossover confinement AL study. The confinement design was adapted from previous ambulatory studies of Vuse Solo (G1 cartridge design) and included product familiarization sessions before each four-hour test session in which subjective measures, nicotine pharmacokinetics (PK), and physiological endpoints were assessed following a single 10-min ad libitum product use session. Product liking, intent to use again, suppression of urge to smoke, and nicotine PK were lower after use of Vuse Solo compared to cigarettes and higher after use of Vuse Solo compared to nicotine gum. No significant differences in blood pressure or heart rate were observed between the products pre- to post-product use. These data reinforce previous research and provide the scientific evidence to support regulatory decisions demonstrating that Vuse Solo has an AL profile lower than that of combustible cigarettes but higher than that of nicotine gum and, therefore, may be a suitable replacement for cigarette smoking for some adult smokers.

Brain health is independently impaired by E-vaping and high-fat diet

Tobacco smoking and high-fat diet (HFD) independently impair short-term memory. E-cigarettes produce e-vapour containing flavourings and nicotine. Here, we investigated whether e-vapour inhalation interacts with HFD to affect short-term memory and neural integrity. Balb/c mice (7 weeks, male) were fed a HFD (43% fat, 20 kJ/g) for 16 weeks. In the last 6 weeks, half of the mice were exposed to tobacco-flavoured e-vapour from nicotine-containing (18 mg/L) or nicotine-free (0 mg/L) e-fluids twice daily. Short-term memory function was measured in week 15. HFD alone did not impair memory function, but increased brain phosphorylated (p)-Tau and astrogliosis marker, while neuron and microglia levels were decreased. E-vapour exposure significantly impaired short-term memory function independent of diet and nicotine. Nicotine free e-vapour induced greater changes compared to the nicotine e-vapour and included, increased systemic cytokines, increased brain p-Tau and decreased postsynaptic density protein (PSD)-95 levels in chow-fed mice, and decreased astrogliosis marker, increased microglia and increased glycogen synthase kinase levels in HFD-fed mice. Increased hippocampal apoptosis was also differentially observed in chow and HFD mice. In conclusion, E-vapour exposure impaired short-term memory independent of diet and nicotine, and was correlated to increased systemic inflammation, reduced PSD-95 level and increased astrogliosis in chow-fed mice, but decreased gliosis and increased microglia in HFD-fed mice, indicating the inflammatory nature of e-vapour leading to short term memory impairment.

Potential for non-combustible nicotine products to reduce socioeconomic inequalities in smoking: a systematic review and synthesis of best available evidence

BACKGROUND

While some experts have emphasised the potential for e-cigarettes to facilitate cessation among smokers with low socioeconomic status (SES), there is limited evidence of their likely equity impact. We assessed the potential for electronic cigarettes and other non-combustible nicotine-containing products (NCNPs) to reduce inequalities in smoking by systematically reviewing evidence on their use by SES in countries at stage IV of the cigarette epidemic.

METHODS

Ten electronic databases were searched in February 2017 using terms relating to e-cigarettes, smokeless tobacco and nicotine replacement therapy (NRT); and SES. We included studies published since 1980 that were available in English and examined product use by SES indicators such as income and education. Data synthesis was based on those studies judged to be of medium- to high-quality using guidelines adapted from the Critical Appraisal Skills Programme.

RESULTS

We identified 54 studies describing NCNP use by SES across 12 countries, of which 27 were judged of sufficient quality to include in data synthesis. We found mixed patterns of e-cigarette current use by SES, with evidence of higher use among low-income adults but unclear or mixed findings by education and occupation. In contrast, smokeless tobacco current use was consistently higher among low SES adults. There was very limited evidence on the SES distribution of NRT in adults and of all NCNPs in young people.

CONCLUSIONS

The only NCNP for which there are clear patterns of use by SES is smokeless tobacco, where prevalence is higher among low SES groups. While this suggests a potentially positive impact on inequalities in smoking (if NCNP use displaces smoked tobacco use), this has not been seen in practice. These findings do not support the suggestion that e-cigarettes have the potential to reduce social inequalities in smoking, since i) current evidence does not show a clear trend of higher e-cigarette use in population groups with higher tobacco consumption, and ii) the experience of smokeless tobacco suggests that - even where NCNP use is higher among low SES groups - this does not necessarily replace smoked tobacco use in these groups.

Impact of non-menthol flavours in e-cigarettes on perceptions and use: an updated systematic review

OBJECTIVES

Given the exponential increase in the use of e-cigarettes among younger age groups and in the growth in research on e-cigarette flavours, we conducted a systematic review examining the impact of non-menthol flavoured e-cigarettes on e-cigarette perceptions and use among youth and adults.

DESIGN

PubMed, Embase, PyscINFO and CINAHL were systematically searched for studies published and indexed through March 2018.

ELIGIBILITY CRITERIA

Quantitative observational and experimental studies that assessed the effect of non-menthol flavours in e-cigarettes on perceptions and use behaviours were included. Specific outcome measures assessed are appeal, reasons for use, risk perceptions, susceptibility, intention to try, initiation, preference, current use, quit intentions and cessation.

DATA EXTRACTION AND SYNTHESIS

Three authors independently extracted data related to the impact of flavours in tobacco products. Data from a previous review were then combined with those from the updated review for final analysis. Results were then grouped and analysed by outcome measure.

RESULTS

The review included 51 articles for synthesis, including 17 published up to 2016 and an additional 34 published between 2016 and 2018. Results indicate that non-menthol flavours in e-cigarettes decrease harm perceptions (five studies) and increase willingness to try and initiation of e-cigarettes (six studies). Among adults, e-cigarette flavours increase product appeal (seven studies) and are a primary reason many adults use the product (five studies). The role of flavoured e-cigarettes on smoking cessation remains unclear (six studies).

CONCLUSION

This review provides summary data on the role of non-menthol flavours in e-cigarette perceptions and use. Consistent evidence shows that flavours attract both youth and adults to use e-cigarettes. Given the clear findings that such flavours increase product appeal, willingness to try and initiation among youth, banning non-menthol flavours in e-cigarettes may reduce youth e-cigarette use. Longitudinal research is needed to examine any role flavours may play in quit behaviours among adults.

Discussions between health professionals and smokers about nicotine vaping products: results from the 2016 ITC Four Country Smoking and Vaping Survey

BACKGROUND AND AIMS

Debate exists about whether health professionals (HPs) should advise smokers to use nicotine vaping products (NVPs) to quit smoking. The objectives were to examine in four countries: (1) the prevalence of HP discussions and recommendations to use an NVP; (2) who initiated NVP discussions; (3) the type of HP advice received about NVPs; and (4) smoker's characteristics related to receiving advice about NVPs.

DESIGN

Cross-sectional study using multivariable logistic regression analyses on weighted data from the 2016 ITC Four Country Smoking and Vaping Survey (ITC 4CV1).

SETTING

Four countries with varying regulations governing the sale and marketing of NVPs: 'most restrictive' (Australia), 'restrictive' (Canada) or 'less restrictive' (England and United States).

PARTICIPANTS

A total of 6615 adult smokers who reported having visited an HP in the last year (drawn from the total sample of 12 294 4CV1 respondents, of whom 9398 reported smoking cigarettes daily or weekly). Respondents were from the United States (n = 1518), England (n = 2116), Australia (n = 1046), and Canada (n = 1935).

MEASUREMENTS

Participants' survey responses indicated if they were current daily or weekly smokers and had visited an HP in the past year. Among those participants, further questions asked participants to report (1) whether NVPs were discussed, (2) who raised the topic, (3) advice received on use of NVPs and (4) advice received on quitting smoking.

FINDINGS

Among the 6615 smokers who visited an HP in the last year, 6.8% reported discussing NVPs with an HP and 2.1% of smokers were encouraged to use an NVP (36.1% of those who had a discussion). Compared with Australia (4.3%), discussing NVPs with an HP was more likely in the United States [8.8%, odds ratio (OR) = 2.15, 95% confidence interval (CI) = 1.41-3.29] and Canada (7.8%, OR = 1.87, 95% CI = 1.26-2.78). Smokers in Australia were less likely to discuss NVPs than smokers in England (6.2%), although this was not statistically significant (OR = 1.47, 95% CI = 0.98-2.20). Overall, the prevalence of HPs recommending NVPs was three times more likely in the United States than in Australia (OR = 3.07, 95% CI = 1.45-6.47), and twice as likely in Canada (OR = 2.28, 95% CI = 1.06-4.87) than in Australia. Australia and England did not differ (OR = 1.76, 95% CI = 0.83-3.74). Just over half (54%) of respondents brought up NVPs themselves; there were no significant differences among countries.

CONCLUSIONS

Discussions in Australia, Canada, England, and the United States between smokers and health professionals about nicotine vaping products appear to be infrequent, regardless of the regulatory environment. A low percentage of health professionals recommended vaping products. This was particularly evident in Australia, which has the most restrictive regulatory environment of the four countries studied.

E-cigarette nicotine dose and flavor: Relationship with appeal, choice, and tobacco use amongst veterans with comorbid psychiatric disorders

BACKGROUND

Electronic cigarettes (EC) may aid some smokers in reducing combustible tobacco use. Smokers with psychiatric co-morbidities tend to have higher nicotine dependence and worse outcomes, so may particularly benefit from alternative cessation aids. EC characteristics, like nicotine level and flavor, may influence EC's appeal to smokers. Nicotine level may impact EC's efficacy in reducing combustible cigarette use.

METHODS

Non-treatment-seeking cigarette smokers with medical/psychiatric co-morbidities rated 'liking' of ECs varying in nicotine level (12 mg, 24 mg) and flavor (menthol, 'slim'-tobacco, 'burley'-tobacco), during an open-label Choice Procedure. Smokers (N = 43) chose ECs for a 4-week take-home-trial, and used EC and/or combustible cigarettes as they wished. Analyses examined ratings and choice by nicotine level and flavor, and the relationship between consistent take-home choice of 12 mg versus 24 mg baseline demographic/smoking characteristics, and outcomes (cigarettes/day, nicotine intake, motivation to quit smoking) during take-home-trial and one-month follow-up.

RESULTS

Smokers who chose menthol-flavor, tobacco-flavor and/or 24 mg nicotine e-liquids for the first take-home week rated these conditions as more 'liked' than alternative options, at baseline. Groups who chose 12 mg versus 24 mg throughout the take-home trial did not significantly differ on baseline characteristics, or smoking-related outcomes within the take-home trial, however, motivation to quit smoking increased more from baseline to one-month follow-up in choosers of higher nicotine (24 mg) ECs.

CONCLUSIONS

Associations between subjective ratings and subsequent choice support feasibility of open-label choice-procedures in EC trials. Access to 12 mg or 24 mg nicotine ECs was associated with reduced smoking, and 24 mg ECs with increased motivation to quit smoking in smokers with medical/psychiatric co-morbidities.

The price of tobacco and its effects on smoking behaviors in Korea: The 2015 Korea Community Health Survey

This study investigated the effects of the price of tobacco on smoking behaviors in Korean adult smokers using a population-based survey. Current smokers or former smokers who quit smoking <1 year prior to the survey were selected from the data of 2015 Korea Community Health Survey (N = 45,686). The effects of the price of tobacco on smoking behaviors were measured. The major effects were defined as quitting, reducing smoking and using electronic cigarettes (e-cigarettes). Chi-square tests and multiple logistic regression analyses were performed. After tobacco prices increased, 3.8%, 22.8% and 5.4% of subjects quit, reduced smoking and switched to e-cigarettes. The adjusted odds ratio (aOR) for reducing smoking was significantly higher in subjects with a lower household income and lower education level than in those with a greater income and higher education level among current smokers. Subjects who started smoking at an older age, who smoked a smaller number of cigarettes smoked per day and who had been exposed to anti-smoking campaigns and anti-smoking information were more likely to reduce smoking after the price of tobacco increased. Younger subjects were less likely to reduce smoking, but they were more likely to use e-cigarettes after the price of tobacco increased. Low-income subjects were sensitive to increases in the price of tobacco. Additional strategies are required to change the smoking behaviors of heavy smokers. Future studies should investigate the long-term effects of increasing the price of tobacco, especially on younger adults, on smoking behaviors.

How do we determine the impact of e-cigarettes on cigarette smoking cessation or reduction? Review and recommendations for answering the research question with scientific rigor

AIMS

To propose a hierarchy of methodological criteria to consider when determining whether a study provides sufficient information to answer the question of whether e-cigarettes can facilitate cigarette smoking cessation or reduction.

DESIGN

A PubMed search to 1 February 2017 was conducted of all studies related to e-cigarettes and smoking cessation or reduction.

SETTINGS

Australia, Europe, Iran, Korea, New Zealand and the United States.

PARTICIPANTS AND STUDIES

91 articles.

MEASUREMENTS

Coders organized studies according to six proposed methodological criteria: (1) examines outcome of interest (cigarette abstinence or reduction), (2) assesses e-cigarette use for cessation as exposure of interest, (3) employs appropriate control/comparison groups, (4) ensures that measurement of exposure precedes the outcome, (5) evaluates dose and duration of the exposure and (6) evaluates the type and quality of the e-cigarette used.

FINDINGS

Twenty-four papers did not examine the outcomes of interest. Forty did not assess the specific reason for e-cigarette use as an exposure of interest. Twenty papers did not employ prospective study designs with appropriate comparison groups. The few observational studies meeting some of the criteria (duration, type, use for cessation) triangulated with findings from three randomized trials to suggest that e-cigarettes can help adult smokers quit or reduce cigarette smoking.

CONCLUSIONS

Only a small proportion of studies seeking to address the effect of e-cigarettes on smoking cessation or reduction meet a set of proposed quality standards. Those that do are consistent with randomized controlled trial evidence in suggesting that e-cigarettes can help with smoking cessation or reduction.

ARDS following oesophagectomy: a comparison of two trials

Introduction

The Beta Agonist Lung Injury Trial-Prevention (BALTI-P) translational substudy and Vitamin D to Prevent Acute Lung Injury Following Oesophagectomy (VINDALOO) trials recruited patients undergoing oesophagectomy, 4 years apart. The acute respiratory distress syndrome (ARDS) rates were lower in the VINDALOO trial. We sought to identify changes between these two trials and identify risk factors for ARDS in oesophagectomy.

Methods

There were data available from 61 patients in the BALTI-P substudy and 68 from VINDALOO. Databases were available for both trials; additional data were collected. Multivariate logistic regression was used to analyse risk factors for ARDS and postoperative complications in the cohorts combined.

Results

Logistic regression analysis showed active smoking was associated with an increase in ARDS (OR 3.91; 95% CI 1.33 to 11.5) and dihydropyridine use (OR 5.34;95% CI 1.56 to 18.3). Hospital length of stay was longer for those who took dihydropyridines (median 29 days (IQR 17–42) vs 13 days (IQR 10–18), P=0.0007) or were diabetic (median 25 days (IQR 14–39) vs 13 (IQR 10–19), P=0.023) but not for current smokers (median in never/ex-smokers 13 (IQR 10–23) vs current smokers 15 (IQR 11–20), P=0.73).

Conclusions

Smoking cessation trials should be promoted. Dihydropyridine effects perioperatively require further clinical and mechanistic evaluation. Patients undergoing oesophagectomy are a useful model for studying perioperative ARDS.

Global approaches to regulating electronic cigarettes

Objectives

Classify and describe the policy approaches used by countries to regulate e-cigarettes.

Methods

National policies regulating e-cigarettes were identified by (1) conducting web searches on Ministry of Health websites, and (2) broad web searches. The mechanisms used to regulate e-cigarettes were classified as new/amended laws, or existing laws. The policy domains identified include restrictions or prohibitions on product: sale, manufacturing, importation, distribution, use, product design including e-liquid ingredients, advertising/promotion/sponsorship, trademarks, and regulation requiring: taxation, health warning labels and child-safety standards. The classification of the policy was reviewed by a country expert.

Results

The search identified 68 countries that regulate e-cigarettes: 22 countries regulate e-cigarettes using existing regulations; 25 countries enacted new policies to regulate e-cigarettes; 7 countries made amendments to existing legislation; 14 countries use a combination of new/amended and existing regulation. Common policies include a minimum-age-of-purchase, indoor-use (vape-free public places) bans and marketing restrictions. Few countries are applying a tax to e-cigarettes.

Conclusions

A range of regulatory approaches are being applied to e-cigarettes globally; many countries regulate e-cigarettes using legislation not written for e-cigarettes.