The Cardiovascular Effects of Electronic Cigarettes

Electronic cigarettes alter cardiac rhythm and heart rate variability hyperacutely in mice

AIMS

There has been an unprecedented rise in electronic cigarette (EC) usage likely because of its perception of being safer than smoking. Recent studies show that EC exposures impact heart rate (HR) and heart rate variability (HRV), but how they are affected by the timing and frequency of exposures remain unclear. We examined the electrocardiographic (EKG) effects induced by brief EC exposures over time, their relation to EC aerosol particle and mass concentrations, and potential to promote prooxidative effects in the lungs.

METHODS & RESULTS

Six 10-week-old C57BL/6J mice, implanted with telemetry devices to monitor EKG activity continuously, were exposed once per week for three weeks to two EC exposures, each lasting 15-min followed by 45-min post-exposure periods. Filtered air (primary) and PBS aerosol (secondary) were used as controls. After combining weeks, EC aerosol induced bradycardia and increased time domain parameters during EC exposures with significant reductions in the post-exposure periods. Log-transformed frequency domain parameters were significantly elevated during and after exposures (p < 0.001). HRV changes occurred within minutes with similar trends observed in particle number and mass concentrations of EC aerosol. HR and HRV varied by week and parameter, with Week 2 and 3 effects overshadowing those in Week 1. ECs induced prooxidative effects in the lungs as evidenced by elevated potential for hydroxyl radical generation in bronchoalveolar lavage fluid of exposed mice (p = 0.003).

CONCLUSION

Short-term EC exposures altered murine HR and HRV within minutes during and after exposures, effects that were modulated by the timing and frequency of EC exposures.

Quitting intentions and behaviours among young Australian e-cigarette users

BACKGROUND AND AIMS

With the prevalence of e-cigarette use among Australian youth increasing significantly in recent years, greater attention is being paid to encouraging and supporting cessation. However, research to inform such efforts is lacking. The present study sought to (i) measure desire to quit e-cigarette use and actual quitting attempts among young Australians and (ii) explore correlates of quitting-related cognitions and behaviours.

DESIGN, SETTING AND PARTICIPANTS

This was a cross-sectional on-line survey conducted in Australia. The participants were 14-25-year-old e-cigarette users (n = 602; 53% women).

MEASUREMENTS

Desire to quit vaping and attempts to quit vaping were the primary dependent variables. The independent variables included several individual (e.g. harm perceptions, perceived appeal of vapes), social (descriptive norms) and environmental (e.g. ease of e-cigarette access) factors.

FINDINGS

A majority of respondents (61%) expressed a desire to quit vaping, and just over half (55%) had made a quit attempt. Finding vapes easy to access was associated with both a lack of desire [odds ratio (OR) = 0.71] and attempts to quit (OR = 0.77), while self-reported addiction to vaping (OR = 1.42 and OR = 3.11) and perceiving vaping to be associated with mental health risks (OR = 1.30 and OR = 1.40) were positively correlated with these variables. Perceiving that vaping is common among people of one's age (OR = 0.82) and finding vapes appealing (OR = 0.55) were associated with a lack of desire to quit, while perceiving vaping to have physical health risks was positively associated with quitting desire (OR = 1.58). School-based education on vaping was associated with reporting an attempt/s to quit (OR = 0.47).

CONCLUSIONS

This survey of young Australian e-cigarette users suggests a high level of desire to quit using e-cigarettes and attempts to quit. Increasing knowledge regarding the physical and mental health risks associated with e-cigarette use may assist with promoting quitting-related intentions. Changing social norms, reducing the accessibility of e-cigarettes and reducing the appeal of the products also constitute potential means of increasing the desire to quit.

Factors associated with susceptibility to e-cigarette use among Australian adolescents

BACKGROUND

Preventing uptake of e-cigarette use among adolescents is critical to minimizing vaping-related harms. To inform the development of effective prevention programs and policies, this study explored potential determinants of susceptibility to e-cigarette use among young Australians.

METHODS

A cross-sectional online survey was administered to 12- to 17-year-old Australians who had never smoked nor vaped (N = 973; 53 % women). The survey assessed susceptibility to e-cigarette use (curiosity about use, willingness to use, and intentions to use) and a comprehensive range of potential correlates that included individual, social, and environmental factors. Regression analyses were conducted to identify factors significantly correlated with each of the dependent variables.

RESULTS

Susceptibility to e-cigarette use was observed in 45 % of respondents. Individual factors associated with susceptibility included respondents' (i) overall opinion of e-cigarettes, (ii) attitudes toward e-cigarettes, (iii) affect regulation expectancies, and (iv) quitting perceptions. Significant social factors included both descriptive and injunctive norms, specifically: perceiving that use is ok for people of one's age, approval from important others to use, and having at least one family member or close friend who vapes.

CONCLUSION

Susceptibility to vaping was observed in a substantial proportion of adolescents who have never smoked. Shifting attitudes and social norms around e-cigarette use appears critical to reducing susceptibility. Recommended prevention efforts include the development of communications addressing misperceptions about the benefits of vaping on affect regulation and stricter regulations on e-cigarette advertising to reduce young Australians' exposure to claims that may result in favourable attitudes to e-cigarette use.

E-cigarettes and arrhythmogenesis: a comprehensive review of pre-clinical studies and their clinical implications

Electronic cigarette use has grown exponentially in recent years, and while their popularity has increased, the long-term effects on the heart are yet to be fully studied and understood. Originally designed as devices to assist with those trying to quit traditional combustible cigarette use, their popularity has attracted use by teens and adolescents who traditionally have not smoked combustible cigarettes. Acute effects on the heart have been shown to be similar to traditional combustible cigarettes, including increased heart rate and blood pressure. The main components of electronic cigarettes that contribute to these arrhythmic effects are found in the e-liquid that is aerosolized and inhaled, comprised of nicotine, flavourings, and a combination of vegetable glycerin (VG) and propylene glycol (PG). Nicotine can potentially induce both ventricular and atrial arrhythmogenesis, with both the atrial and ventricular effects resulting from the interactions of nicotine and the catecholamines they release via potassium channels. Atrial arrhythmogenesis, more specifically atrial fibrillation, can also occur due to structural alterations, which happens because of nicotine downregulating microRNAs 133 and 590, both post-transcriptional growth factor repressors. Liquid flavourings and the combination of PG and VG can possibly lead to arrhythmic events by exposing users to acrolein, an aldehyde that stimulates TRPA1 that in turn causes a change towards sympathetic activation and autonomic imbalance. The design of these electronic delivery devices is constantly changing; therefore, it has proven extremely difficult to study the long-term effects on the heart caused by electronic cigarettes but will be important to understand given their rising popularity. The arrhythmic effects of electronic cigarettes appear similar to traditional cigarettes as well; however, a comprehensive review has not been compiled and is the focus of this article.

Electronic Cigarette Harms: Aggregate Evidence Shows Damage to Biological Systems

Evidence of the harms of e-cigarettes has been unfolding slowly and has been documented in many reviews and reports worldwide. A narrative review of new evidence is presented since, as research has continued, newly aggregated evidence of the dangers of electronic cigarettes on the brain, heart, and lungs is vital to inform decisions on restricting the use of e-cigarettes. Several biomedical research databases were searched for electronic cigarette health effects, emphasizing reviews, systematic reviews, and meta-analyses. Over 50 review studies, primarily in 2022 and 2023, illustrate some of the latest information on e-cigarette harms. Results show studies of respiratory, neurological, and cardiovascular effects. Researchers call for expanding studies through new methods to elaborate on initial findings of multiple harms emerging in clinical investigations. Since the use of electronic cigarettes for adult cessation is not sanctioned in most countries, it is clear that health authorities see significant costs to the health of the general population if the promotion and use of electronic cigarettes occur worldwide. Regulatory action to control electronic cigarettes should consider the substantial evidence of electronic cigarette harm.

Examining Disparities in Current E-Cigarette Use among U.S. Adults before and after the WHO Declaration of the COVID-19 Pandemic in March 2020

This paper aims to estimate the prevalence of e-cigarette use before and after the COVID-19 pandemic declaration and to delineate disparities in use across subpopulations. Data were derived from the 2020 Health Information National Trends Survey (N = 3865) to conduct weighted multivariable logistic regression and marginal analyses. The overall prevalence of current e-cigarette use increased from 4.79% to 8.63% after the COVID-19 pandemic declaration. Furthermore, non-Hispanic Black people and Hispanic people had lower odds of current e-cigarette use than non-Hispanic White people, but no significant differences were observed between groups before the pandemic. Compared to heterosexual participants, sexual minority (SM) participants had higher odds of current e-cigarette use after the declaration, with insignificant differences before. People who had cardiovascular disease conditions, relative to those without, had higher odds of current e-cigarette use after the declaration, but no group differences were found before the declaration. The marginal analyses showed that before and after the pandemic declaration, SM individuals had a significantly higher probability of using e-cigarettes compared to heterosexual individuals. These findings suggest the importance of adopting a subpopulation approach to understand and develop initiatives to address substance use, such as e-cigarettes, during pandemics and other public health emergencies.

Perceptions of e-cigarettes among Australian adolescents, young adults, and adults

Increases in e-cigarette use are of concern to public health authorities given the harms associated with vaping. Understanding people's perceptions of the risks and benefits of e-cigarette use has the potential to assist with prevention efforts. However, research assessing the perceptions of Australian adolescents and any differences in perceptions between adolescents, young adults, and adults is limited. Additionally, research exploring perceptions of various types of e-cigarettes is lacking. To inform the development of prevention and intervention programs and policies, this study aimed to explore Australians' perceptions of the risks and benefits associated with e-cigarette use and whether perceptions differ by age and user status. A sample of 4,617 Australians aged 12 + years completed an online survey that assessed (i) smoking and e-cigarette user status, (ii) e-cigarette risk perceptions, (iii) beliefs about e-cigarettes as a smoking cessation tool, and (iv) positive e-cigarette outcome expectancies. Across all age groups, respondents perceived non-nicotine and flavoured e-cigarettes as less harmful than nicotine e-cigarettes. Significantly more adolescents and young adults than adults held positive outcome expectancies, and a substantial minority of non-users and never users in all age groups believed that using e-cigarettes confers social and mental health benefits. Given the potential benefits they perceived to be associated with e-cigarette use, a substantial proportion of adolescent and young adult never users may be vulnerable to initiation. These findings highlight the importance of (i) adequately communicating the risks associated with non-nicotine e-cigarette use and (ii) addressing misperceptions about use, especially among youth.

Cardiometabolic Care: Assessing Patients with Diabetes Mellitus with No Overt Cardiovascular Disease in the Light of Heart Failure Development Risk

The mechanisms leading to the development of heart failure (HF) in diabetes mellitus (DM) patients are multifactorial. Assessing the risk of HF development in patients with DM is valuable not only for the identification of a high-risk subgroup, but also equally important for defining low-risk subpopulations. Nowadays, DM and HF have been recognized as sharing similar metabolic pathways. Moreover, the clinical manifestation of HF can be independent of LVEF classification. Consequently, approaching HF should be through structural, hemodynamic and functional evaluation. Thus, both imaging parameters and biomarkers are important tools for the recognition of diabetic patients at risk of HF manifestation and HF phenotypes, and arrhythmogenic risk, and eventually for prognosis, aiming to improve patients' outcomes utilizing drugs and non-pharmaceutical cardioprotective tools such as diet modification.

The association between electronic cigarettes, sleep duration, and the adverse cardiovascular outcomes: Findings from behavioral risk factor surveillance system, 2020

The joint effect of electronic cigarette smoking and insufficient sleep duration on cardiovascular disease (CVD) was unclear. This cross-sectional study aimed to evaluate the association between electronic cigarettes, sleep duration, and risk of CVD among American adults. The participants who completed the survey from the behavioral risk factor surveillance system in 2020 were included in this study. The status of electronic cigarette smoking was divided into never, former, and current use. The duration of sleep was categorized into insufficient (<6 h), appropriate (6–9 h), and excessive (>9 h) groups. The CVD group was defined as a patient having any of the following conditions: heart attack, coronary heart disease, or stroke according to self-report. The multivariate logistic regression model was adopted to determine the association between electronic cigarettes, sleep duration, and the risk of CVD. Sensitivity analyses were performed to assess the joint effects on the risk of CVD subtypes, including heart attack, coronary heart disease, and strokes, respectively. Subgroup analyses were performed to estimate the joint effects within the stratum of the age group. The total number of participants included in the present study was 253,561. Of which, 22,908 patients had CVD. In total, 61,293 participants had previously or currently used electronic cigarettes and 37,429 participants had inappropriate sleep duration. Former electronic cigarette users had a 10.8% increased risk of having CVD (OR = 1.108, 95% CI: 1.001–1.227) compared to users who never had electronic cigarettes. Insufficient and excessive sleep durations are associated with increased risks of CVD (OR = 1.592, 95% CI: 1.460–1.735; OR = 1.523, 95% CI: 1.320–1.758). The participants with current vaping status and lack of sleep had a 159.6% increased risk of CVD (OR = 2.596, 95% CI: 1.810–3.723). Sensitivity analyses found similar joint effects of current vaping and insufficient sleep on the risk of heart attack, coronary heart attack, and stroke. The subgroup analyses across each age stratum found that the middle-aged group is most vulnerable to the joint effect of current vaping and insufficient sleep. This study found that both current vaping and inappropriate sleep duration were associated with CVD. Additionally, there was a significant joint effect of current vaping and insufficient sleep on the risk of CVD, especially for middle-aged participants.