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

[Intended and unintended effects of e-cigarettes in clinical studies: a plea for (more) transparency]

E-cigarettes are used in clinical trials to facilitate smoking cessation. Due to the health risks associated with the use of e-cigarettes, the results of clinical trials should be fully reported, including continued exclusive use and dual use of tobacco and e-cigarettes. Nicotine cessation outcomes should be reported as the primary endpoint as well as the analysis of tobacco cessation alone. As there is currently no robust evidence that reducing cigarette consumption provides substantial health benefits, cigarette consumption reduction should not be used as a health outcome in clinical trials. Continued nicotine dependence should be included as an "adverse event" in the reporting of trial results.

Associations between ENDS and cigarette use, and compromised immunity in US adults: Findings from the 2021-2022 NHIS

BACKGROUND

Tobacco use presents increased risks for individuals with weakened immune systems (WIS). We investigated the association between cigarette and electronic nicotine delivery systems (ENDS or e-cigarettes) use and WIS in US adults using data from the 2021-2022 National Health Interview Survey.

METHODS

Data from 57,133 adults were analyzed, focusing on WIS prevalence due to health conditions, prescriptions, or both. Cigarette and ENDS use were categorized as never, former, or current. Weighted multivariable regression models adjusted for demographics and other health conditions to assess associations between tobacco use and WIS.

RESULTS

Among US adults, 4.3% had prescription-related WIS, 4.6% had health condition-related WIS, and 7% had WIS due to either reason. Adjusted results from multivariable regression models indicated that adults with WIS due to health conditions were more likely to be current (AOR = 1.21, 95%CI: 1.05-1.40) and former (AOR = 1.25, 95%CI: 1.11-1.39) cigarette smokers compared to counterparts without WIS. Adults with WIS due to prescriptions were more likely to be former cigarette smokers (AOR = 1.19, 95%CI: 1.06-1.34). Those with WIS for any reason were more likely to be current (AOR = 1.19, 95%CI: 1.05-1.35) and former (AOR = 1.24, 95%CI: 1.13-1.36) cigarette smokers. Adults with WIS due to health conditions (AOR = 1.23, 95%CI: 1.06-1.41) or any reasons (AOR = 1.19, 95%CI:1.05-1.34) were more likely to be former ENDS users compared to those without WIS.

CONCLUSIONS

In this nationally representative study, we found a notable link between cigarette and ENDS use with WIS, particularly among those with health condition-related or prescription-related WIS, underscoring the importance of addressing tobacco use in this vulnerable population.

Altered insular functional activity among electronic cigarettes users with nicotine dependence

Electronic cigarettes (e-cigs) use, especially among youngsters, has been on the rise in recent years. However, little is known about the long-term effects of the use of e-cigs on brain functional activity. We acquired the resting-state functional magnetic resonance imaging (rs-fMRI) data from 93 e-cigs users with nicotine dependence and 103 health controls (HC). The local synchronization was analyzed via the regional homogeneity (ReHo) method at voxel-wise level. The functional connectivity (FC) between the nucleus accumbens (NAcc), the ventral tegmental area (VTA), and the insula was calculated at ROI-wise level. The support vector machining classification model based on rs-fMRI measures was used to identify e-cigs users from HC. Compared with HC, nicotine-dependent e-cigs users showed increased ReHo in the right rolandic operculum and the right insula (p < 0.05, FDR corrected). At the ROI-wise level, abnormal FCs between the NAcc, the VTA, and the insula were found in e-cigs users compared to HC (p < 0.05, FDR corrected). Correlation analysis found a significant negative correlation between ReHo in the left NAcc and duration of e-cigs use (r = -0.273, p = 0.008, FDR corrected). The following support vector machine model based on significant results of rs-fMRI successfully differentiates chronic e-cigs users from HC with an accuracy of 73.47%, an AUC of 0.781, a sensitivity of 67.74%, and a specificity of 78.64%. Dysregulated spontaneous activity and FC of addiction-related regions were found in e-cigs users with nicotine dependence, which provides crucial insights into the prevention of its initial use and intervention for quitting e-cigs.

Associations Between Noticing E-Cigarette Advertising Features and E-Cigarette Appeal and Switching Interest Among Young Adult Dual Users

BACKGROUND

E-cigarette advertising, which often includes various features, may prompt e-cigarette use and product switching. This study examined the associations between noticing e-cigarette ad features and perceived product appeal and interest in completely switching from cigarettes to advertised e-cigarettes among young adult dual users of both products.

METHODS

We analyzed data from an online heatmap experiment among young adult dual users defined as established cigarette smokers who currently used e-cigarettes (ages 18-34 years; n = 1,821). Participants viewed 12 e-cigarette ads, clicked on ad features (e.g., fruit flavors, nicotine warnings, price promotions, smoker-targeted claims) that attracted their attention (defined as "noticing"), and answered questions about e-cigarette product appeal and interest in completely switching from cigarettes to the e-cigarettes shown. We examined within-person associations between noticing specific ad features and outcomes, controlling for demographic and tobacco use-related characteristics.

RESULTS

Noticing fruit flavors (AOR = 1.67 and 1.28) and fruit images (AOR = 1.53 and 1.21) was positively associated with having any e-cigarette product appeal and switching interest. Noticing price promotions (AOR = 1.23) was positively associated with product appeal. In contrast, noticing nicotine warnings (AOR = 0.74 and 0.86), smoker-targeted claims (AOR = 0.78 and 0.89), and tobacco flavors (AOR = 0.92 and 0.90) was negatively associated with product appeal and switching interest.

CONCLUSIONS

Noticing certain e-cigarette ad features (e.g., fruit flavors and nicotine warnings) may be associated with product appeal and/or switching interest among young adult dual users. More research is needed to assess the influence of e-cigarette ad features that promote product switching interests among cigarette smokers while discourage interests among tobacco-naïve individuals.

Perceptions of a reduced nicotine policy and predictors of policy support: A nationally representative U.S. survey

BACKGROUND

The U.S. Food and Drug Administration is considering a policy to reduce nicotine in cigarettes to non-addictive levels. Although current evidence supports the public-health benefits of a reduced-nicotine policy, almost half of people who smoke (∼ 40%) do not support the policy. This study estimates the factors most strongly associated with support or opposition toward the policy, including tobacco use status, perceived effects of a reduced nicotine policy, trust in the FDA, and psychological distress. The study aims to inform messaging campaigns and policy makers.

METHODS

Data were collected in 2021 with nationally representative samples of U.S. adults (n = 1763). After receiving information about the reduced nicotine policy, participants indicated their beliefs and support for or opposition to the policy, along with other individual difference characteristics. Univariate population parameters and multinomial logistic regression coefficients were estimated.

RESULTS

In adjusted models, people who formerly or never smoked were less likely to oppose the policy compared to those who currently smoke; people with higher psychological distress and those who believe the policy will promote switching to e-cigarettes were more likely to oppose the policy. In addition, people were more likely to support the policy if they believed it would make quitting easier or that the FDA is trustworthy.

CONCLUSIONS

Educational campaigns about reduced nicotine policy should expect higher impact by targeting prevalent perceptions and those more strongly associated with policy sentiment. In anticipation of the policy rollout, there may be a critical window to shape public opinion.

Prevalence of Cigarette Smoking, E-cigarette Use, and Dual Use Among Urban and Rural Women During the Peripartum Period, PRAMS 2015-2020

OBJECTIVES

Evidence has emerged on the health dangers of electronic cigarette (e-cigarette) use among pregnant women and neonates. We examined whether rural residence is a risk factor for smoking and e-cigarette use among women during the peripartum period in the United States.

METHODS

This study was based on pooled cross-sectional 2015-2020 data from the Pregnancy Risk Assessment Monitoring System. The outcome was exclusive smoking, exclusive e-cigarette use, and use of both products (ie, dual use) versus use of neither tobacco product by women with live infants aged 2 to 6 months. We examined rural-urban differences in outcome by using univariate and multivariable multinomial logistic regressions with post hoc contrasts and marginal analyses, adjusting for complex survey design and nonresponse.

RESULTS

During the peripartum period, 5.0% of women were smoking combustible cigarettes, 5.0% were using e-cigarettes, and 1.9% were using both tobacco products. The crude prevalence of e-cigarette use was 1.1 percentage point higher, and the adjusted prevalence was 0.8 percentage points lower for rural versus urban women (P < .001 for both). Among rural women, 6.7% (95% CI, 6.3%-7.1%) smoked combustible cigarettes exclusively and 2.6% (95% CI, 2.3%-2.8%) used both products, as compared with 4.5% (95% CI, 4.4%-4.8%) and 1.7% (95% CI, 1.6%-1.8%) of urban women, respectively, adjusting for sociodemographic and health-related characteristics.

CONCLUSIONS

Maternal sociodemographic and health-related characteristics differed by combustible smoking versus e-cigarette use during the peripartum period. The effect of residence on e-cigarette use was significantly confounded by sociodemographic and health-related characteristics, resulting in clinically comparable prevalence of e-cigarette use in rural and urban mothers with live infants aged 2 to 6 months.

Relationship between electronic cigarette use, dual smoking habits, and psychological distress among youth in Northern Thailand: A cross-sectional study

INTRODUCTION

Amidst the escalating trend of electronic cigarette (e-cigarette) use and dual smoking habits among youth, understanding their potential impact on psychological well-being is imperative. Limited research has explored this relationship, particularly among youth in settings where e-cigarettes are banned. This study investigates the relationship between current e-cigarette and traditional cigarette use patterns and the presence of depression and anxiety symptoms among youth in Thailand.

METHODS

Using a cross-sectional survey encompassing 3424 individuals aged 15-24 years in Northern Thailand from December 2021 to September 2022, we accessed cigarette and e-cigarette usage over the past 30 days alongside depression and anxiety symptoms over the past two weeks. Multivariable logistic regression was employed to analyze the association of these variables, adjusting for sociodemographic factors.

RESULTS

Among the surveyed youths, 10.8% reported cigarette use, 6.2% utilized e-cigarettes, and 3.3% were dual users within the past 30 days. Regarding mental health, 33.96% exhibited moderate-severe to severe depression, while 52.54% experienced anxiety at similar levels. After adjusting for covariates, both current e-cigarette users and dual users exhibited heightened depression symptoms (AOR=1.80; 95% CI: 1.30-2.51, and AOR=2.30; 95% CI: 1.49-3.55, respectively) and only e-cigarette use had increased odds of increased anxiety levels (AOR=1.70; 95% CI: 1.24-2.32) compared to non-users. Notably, current cigarette smokers demonstrated no association with depression but had decreased odds of higher levels of anxiety compared to non-users (AOR=0.73; 95% CI: 0.55-0.96).

CONCLUSIONS

A substantial number of Thai youths are using e-cigarettes and experiencing psychological distress. E-cigarette use is associated with heightened levels of depression and anxiety, whereas cigarette smoking is not associated with depression but is likely to be associated with an increased reporting of anxiety. These contradictory findings highlight the need for comprehensive investigations, especially when e-cigarettes are prohibited.

The potential impact of removing a ban on electronic nicotine delivery systems using the Mexico smoking and vaping model (SAVM)

Objective

To develop the Mexico Smoking and Vaping Model (Mexico SAVM) to estimate cigarette and electronic nicotine delivery systems (ENDS) prevalence and the public health impact of legalizing ENDS use.

Methods

SAVM, a cohort-based discrete-time simulation model, compares two scenarios. The ENDS-Restricted Scenario estimates smoking prevalence and associated mortality outcomes under the current policy of an ENDS ban, using Mexico-specific population projections, death rates, life expectancy, and smoking and e-cigarette prevalence. The ENDS-Unrestricted Scenario projects smoking and vaping prevalence under a hypothetical scenario where ENDS use is allowed. The impact of legalizing ENDS use is estimated as the difference in smoking- and vaping-attributable deaths (SVADs) and life-years lost (LYLs) between the ENDS-Restricted and Unrestricted scenarios.

Results

Compared to a national ENDS ban, The Mexico SAVM projects that legalizing ENDS use could decrease smoking prevalence by 40.1% in males and 30.9% in females by 2049 compared to continuing the national ENDS ban. This reduction in prevalence would save 2.9 (2.5 males and 0.4 females) million life-years and avert almost 106 (91.0 males and 15.5 females) thousand deaths between 2025 and 2049. Public health gains decline by 43% to 59,748 SVADs averted when the switching rate is reduced by half and by 24.3% (92,806 SVADs averted) with a 25% ENDS risk level from that of cigarettes but increased by 24.3% (121,375 SVADs averted) with the 5% ENDS risk.

Conclusions

Mexico SAVM suggests that greater access to ENDS and a more permissive ENDS regulation, simultaneous with strong cigarette policies, would reduce smoking prevalence and decrease smoking-related mortality. The unanticipated effects of an ENDS ban merit closer scrutiny, with further consideration of how specific ENDS restrictions may maximize public health benefits.

The prevalence and sociodemographic determinants of tobacco and nicotine use among students in healthcare disciplines in Saudi Arabian universities: a cross-sectional survey

Background

Tobacco smoking is one of the most significant health-related problems worldwide. However, the prevalence and sociodemographic determinants of tobacco and nicotine use among students on healthcare courses in Saudi Arabia are limited.

Methods

This cross-sectional study used a questionnaire that was distributed via SurveyMonkey between November 2022 and June 2023 to all student universities offering healthcare courses. Data are presented as frequency and percentages. The associated sociodemographic factors with current tobacco and nicotine use were subjected to logistic regression.

Results

Overall, 5,012, of whom 3,872 (77.25%) were males, responded to the online survey. The prevalence of current tobacco and nicotine use was 3,553 (71%). The majority of users used electronic nicotine delivery systems (1,622: 32.36%). The current use of cigarettes (AOR: 1.75 (1.42 to 2.15)), e-cigarettes (AOR: 1.17 (1.01 to 1.37)), and smokeless tobacco substances (AOR: 1.35 (1.02 to 1.90)) were more pronounced among males compared to female students. However, the current use of a hookah was less among males (AOR: 0.74 (95% CI: 61 to 0.91)). Smoking cigarettes was practiced less among students living in other regions compared to the Central Region. However, smokeless tobacco substances seem to be more prevalent in the Western, Southern, and Northern Regions, (AOR: 1.57 (95% CI: 1.09 to 2.26)), (AOR: 1.43 (95% CI: 1.04 to 1.95)), and (AOR: 1.57 (95% CI: 1.09 to 2.26)), respectively.

Conclusion

Smoking is prevalent among students in the healthcare disciplines, with electronic nicotine delivery systems being the most used product. Several sociodemographic factors were associated with higher tobacco or nicotine use.

Population-Based Disease Odds for E-Cigarettes and Dual Use versus Cigarettes

BACKGROUND: E-cigarettes are promoted as less harmful than cigarettes. There has not been a direct comparison of health effects of e-cigarettes or dual use (concurrently using e-cigarettes and cigarettes) with those of cigarettes in the general population. METHODS: Studies in PubMed, EMBASE, Web of Science, and PsychINFO published through October 1, 2023, were pooled in a random-effects meta-analysis if five or more studies were identified with a disease outcome. We assessed risk of bias with Risk Of Bias In Non-randomized Studies of Exposure and certainty with Grading of Recommendations, Assessment, Development, and Evaluations. Outcomes with fewer studies were summarized but not pooled. RESULTS: We identified 124 odds ratios (94 cross-sectional and 30 longitudinal) from 107 studies. Pooled odds ratios for current e-cigarette versus cigarette use were not different for cardiovascular disease (odds ratio, 0.81; 95% confidence interval, 0.58 to 1.14), stroke (0.73; 0.47 to 1.13), or metabolic dysfunction (0.99; 0.91 to 1.09) but were lower for asthma (0.84; 0.74 to 0.95), chronic obstructive pulmonary disease (0.53; 0.38 to 0.74), and oral disease (0.87; 0.76 to 1.00). Pooled odds ratios for dual use versus cigarettes were increased for all outcomes (range, 1.20 to 1.41). Pooled odds ratios for e-cigarettes and dual use compared with nonuse of either product were increased (e-cigarette range, 1.24 to 1.47; dual use, 1.49 to 3.29). All included studies were assessed as having a low risk of bias. Results were generally not sensitive to study characteristics. Limited studies of other outcomes suggest that e-cigarette use is associated with additional diseases. CONCLUSIONS: There is a need to reassess the assumption that e-cigarette use provides substantial harm reduction across all cigarette-caused diseases, particularly accounting for dual use.

[Electronic cigarettes: harm reduction or harm prolongation?]

This paper deals with the question of whether electronic cigarettes (e-cigarettes) can minimize the proven harm of smoking tobacco or may lead to a long-term harm. While the British Royal College of Physicians recommends smokers to use e-cigarettes as a substitute for tobacco products, the German Society for Pneumology and Respiratory Medicine advises smokers against using e-cigarettes. The harm reduction strategy is based on three hypotheses. Hypothesis 1: It is assumed that e-cigarettes cause less damage to health than tobacco cigarettes. Hypothesis 2: It is postulated that smokers are motivated to switch from conventional cigarettes to e-cigarettes. Hypothesis 3: It is assumed that e-cigarettes are an effective means for quitting smoking with few side effects. Although the long-term health consequences of e-cigarette use remain unknown, there is increasing evidence that e-cigarettes are toxic, harmful to cardiovascular system, respiratory health and potentially carcinogenic. Population-representative epidemiological surveys have shown that three-quarters of all current e-cigarette users in Germany smoke tobacco at the same time. In a few randomized clinical trials, e-cigarettes showed higher success rates compared to nicotine replacement products. As over-the-counter consumer products, a large number of studies have found no advantage for e-cigarettes under real conditions. In addition, e-cigarettes prolong nicotine dependence compared to nicotine replacement products. According to the current state of knowledge, the hypotheses behind the harm minimization strategy using e-cigarettes must be regarded as refuted. It therefore appears ethically problematic when doctors recommend e-cigarettes to their patients as a substitute for smoking.