Adding Data From 2015 Strengthens the Association Between E-Cigarette Use and Myocardial Infarction

Electronic cigarettes and cardiovascular disease: epidemiological and biological links

Electronic cigarettes (e-cigarettes), as alternative nicotine delivery methods, has rapidly increased among youth and adults in recent years. However, cardiovascular safety is an important consideration regarding e-cigarettes usage. e-cigarette emissions, including nicotine, propylene glycol, flavorings, nitrosamine, and metals, might have adverse effects on cardiovascular health. A large body of epidemiological evidence has indicated that e-cigarettes are considered an independent risk factor for increased rates of cardiovascular disease occurrence and death. The incidence and mortality of various types of cardiovascular disease, such as cardiac arrhythmia, hypertension, acute coronary syndromes, and heart failure, have a modest growth in vapers (users of e-cigarettes). Although the underlying biological mechanisms have not been fully understood, studies have validated that oxidative stress, inflammation, endothelial dysfunction, atherosclerosis, hemodynamic effects, and platelet function play important roles in which e-cigarettes work in the human body. This minireview consolidates and discusses the epidemiological and biological links between e-cigarettes and various types of cardiovascular disease.

E-cigarette exposure augments murine abdominal aortic aneurysm development: role of Chil1

AIMS

Abdominal aortic aneurysm (AAA) is a common cardiovascular disease with a strong correlation to smoking, although underlying mechanisms have been minimally explored. Electronic cigarettes (e-cigs) have gained recent broad popularity and can deliver nicotine at comparable levels to tobacco cigarettes, but effects on AAA development are unknown.

METHODS AND RESULTS

We evaluated the impact of daily e-cig vaping with nicotine on AAA using two complementary murine models and found that exposure enhanced aneurysm development in both models and genders. E-cigs induced changes in key mediators of AAA development including cytokine chitinase-3-like protein 1 (CHI3L1/Chil1) and its targeting microRNA-24 (miR-24). We show that nicotine triggers inflammatory signalling and reactive oxygen species while modulating miR-24 and CHI3L1/Chil1 in vitro and that Chil1 is crucial to e-cig-augmented aneurysm formation using a knockout model.

CONCLUSIONS

In conclusion our work shows increased aneurysm formation along with augmented vascular inflammation in response to e-cig exposure with nicotine. Further, we identify Chil1 as a key mediator in this context. Our data raise concerns regarding the potentially harmful long-term effects of e-cig nicotine vaping.

Time-varying association between cigarette and ENDS use on incident hypertension among US adults: a prospective longitudinal study

OBJECTIVE

Electronic nicotine delivery systems (ENDS) products have emerged as the most popular alternative to combustible cigarettes. However, ENDS products contain potentially dangerous toxicants and chemical compounds, and little is known about their health effects. The aim of the present study was to examine the prospective association between cigarette and ENDS use on self-reported incident hypertension.

DESIGN

Longitudinal cohort study.

SETTING

Nationally representative sample of the civilian, non-institutionalised population in the USA.

PARTICIPANTS

17 539 adults aged 18 or older who participated at follow-up and had no self-reported heart condition or previous diagnosis of hypertension or high cholesterol at baseline.

MEASURES

We constructed a time-varying tobacco exposure, lagged by one wave, defined as no use, exclusive established use (every day or some days) of ENDS or cigarettes, and dual use. We controlled for demographics (age, sex, race/ethnicity and household income), clinical risk factors (family history of heart attack, obesity, diabetes and binge drinking) and smoking history (cigarette pack-years).

OUTCOMES

Self-reported incident hypertension diagnosis.

RESULTS

The self-reported incidence of hypertension was 3.7% between wave 2 and wave 5. At baseline, 18.0% (n=5570) of respondents exclusively smoked cigarettes; 1.1% (n=336) exclusively used ENDS; and 1.7% (n=570) were dual users. In adjusted models, exclusive cigarette use was associated with an increased risk of self-reported incident hypertension compared with non-use (adjusted HR (aHR) 1.21, 95% CI 1.06 to 1.38), while exclusive ENDS use (aHR 1.00, 95% CI 0.68 to 1.47) and dual use (aHR 1.15, 95% CI 0.87 to 1.52) were not.

CONCLUSIONS

We found that smoking increased the risk of self-reported hypertension, but ENDS use did not. These results highlight the importance of using prospective longitudinal data to examine the health effects of ENDS use.

The Impact of Vaping on Primary Spontaneous Pneumothorax Outcomes

INTRODUCTION

Cigarette smoking is associated with primary spontaneous pneumothorax (PSP). Electronic cigarettes (E-cigarettes) are touted as a healthier alternative to cigarettes; however, the impact E-cigarette use has on PSP management is not known. The goal of this study was to determine if E-cigarette use is associated with inferior outcomes after PSP, compared to never smokers and cigarette smokers.

METHODS

We conducted a retrospective cohort study of patients in a large tertiary care hospital system in an urban area who presented with PSP from September 2015 through February 2019. Primary spontaneous pneumothorax patients were identified from the institutional Society of Thoracic Surgeon (STS) database. Patients with pneumothoraces from traumatic, iatrogenic, and secondary etiologies were excluded. Baseline clinical and demographic data and outcomes including intervention(s) required, length of stay, and recurrence were evaluated.

RESULTS

Identified were 71 patients with PSP. Seventeen (24%) had unverifiable smoking history. Of the remaining, 7 (13%) currently vaped, 27(50%) currently smoked cigarettes, and 20(37%) were never smokers. Mean age was 33 years; 80% male. All vapers required tube thoracostomy vs 74% of current smokers and 75% of never smokers. Vaping was associated with increased odds of recurrence compared to never smokers (OR 2.00, 95% CI 0.35,11.44). Vapers had the shortest median time to recurrence after initial hospitalization (10 d[4,18] v 20 d[5,13] cigarette smokers v 27 d[13 275] never smokers, P < .001).

CONCLUSION

Vaping may complicate PSP outcomes. As vaping use increases, especially among adolescents, it is imperative that the manner of tobacco use is documented and considered when caring for patients, especially those with pulmonary problems.

Re-examining the Association Between E-Cigarette Use and Myocardial Infarction: A Cautionary Tale

INTRODUCTION

Cross-sectional analyses have suggested that e-cigarette use, independent of combustible cigarette use, elevates the risk of myocardial infarction. Previous researchers confused their own models' assumptions that these risks were independent with the idea that their analyses validated the presence of independent risks. This study avoids this pitfall.

METHODS

Cross-sectional analyses of the 2014-2019 National Health Interview Surveys (N=175,546) were conducted in 2020.

RESULTS

Logistic regressions found that e-cigarette use was associated with having had a myocardial infarction, but this association significantly varied on the basis of one's smoking history. With a host of demographic and clinical variables controlled, e-cigarette use was associated with lifetime myocardial infarction occurrence only among current smokers. A counterfactual analysis first removed all (current or former) e-cigarette‒using respondents who had suffered a myocardial infarction without a history of smoking. The independent-effects model used in previous research misleadingly indicated that daily vaping increases never smokers' odds of having had a myocardial infarction by 1.55 (95% CI=1.11, 2.15), even though no such myocardial infarction sufferers remained in the analyzed data. The association between myocardial infarction and vaping daily has shown a significant annual decline (AOR=0.81, 95% CI=0.67, 0.98).

CONCLUSIONS

There is no reliable evidence that e-cigarette use is associated with ever having had a myocardial infarction among never smokers. Contrary to concerns that the harms associated with e-cigarettes are only now emerging after more years of possible product use, the only evidence of time-dependent variation in the association between e-cigarette use and myocardial infarction ran counter to this possibility. The scientific community must insist that researchers engage in accurate public communication of peer-reviewed findings.

E-Cigarette Use and Adult Cigarette Smoking Cessation: A Meta-Analysis

Objectives. To determine the association between e-cigarette use and smoking cessation.Methods. We searched PubMed, Web of Science Core Collection, and EMBASE and computed the association of e-cigarette use with quitting cigarettes using random effects meta-analyses.Results. We identified 64 papers (55 observational studies and 9 randomized clinical trials [RCTs]). In observational studies of all adult smokers (odds ratio [OR] = 0.947; 95% confidence interval [CI] = 0.772, 1.160) and smokers motivated to quit smoking (OR = 0.851; 95% CI = 0.684, 1.057), e-cigarette consumer product use was not associated with quitting. Daily e-cigarette use was associated with more quitting (OR = 1.529; 95% CI = 1.158, 2.019) and less-than-daily use was associated with less quitting (OR = 0.514; 95% CI = 0.402, 0.665). The RCTs that compared quitting among smokers who were provided e-cigarettes to smokers with conventional therapy found e-cigarette use was associated with more quitting (relative risk = 1.555; 95% CI = 1.173, 2.061).Conclusions. As consumer products, in observational studies, e-cigarettes were not associated with increased smoking cessation in the adult population. In RCTs, provision of free e-cigarettes as a therapeutic intervention was associated with increased smoking cessation.Public Health Implications. E-cigarettes should not be approved as consumer products but may warrant consideration as a prescription therapy.