Are e-cigarette use and vaping associated with increased respiratory symptoms and poorer lung function in a population exposed to smoke from a coal mine fire?

E-cigarette use and respiratory symptoms in adults: A systematic review and meta-analysis

INTRODUCTION

Electronic cigarette (e-cigarette) use is gaining popularity among adults. Monitoring e-cigarette-induced respiratory symptoms is crucial for both clinical and regulatory purposes. We systematically reviewed the current literature to understand the prevalence of respiratory symptoms among exclusive e-cigarette users, dual users, and former smokers.

METHODS

Databases searched included PubMed, CINAHL, Cochrane Library, Embase, and Scopus. We included all English-language, empirical quantitative articles that explored the prevalence of e-cigarette-related respiratory symptoms. Random-effects models were utilized in conducting the meta-analyses. The quality of identified studies was evaluated using the NIH Study Quality Assessment Tools. This study is registered with PROSPERO(#CRD42020165973).

RESULTS

The literature search identified 1240 references. After removing duplicates and screening for eligibility, 168 studies were included in the final review. The majority of included studies reported a wide range of adverse respiratory symptoms. The respiratory symptoms were prevalent among the exclusive e-cigarette users, dual users, and those who switched from combustible cigarettes to e-cigarettes. Further, out of the RCT studies, 5 were rated as good quality, while 3 were rated as fair. Among the observational studies, 24 were rated as good quality, and 9 were rated as fair. The two experimental studies were both rated as fair quality.

CONCLUSIONS

Continued monitoring of respiratory symptoms among e-cigarette users is warranted. Due to the heterogeneity and inconsistencies among studies, which limit result interpretation and highlight the need for studies assessing causal inference, further research using robust study designs is essential. This will provide clinicians with comprehensive knowledge about the potential respiratory risks of e-cigarette use.

The relationship between chronic lung disease diagnosis and the susceptibility to e-cigarette use in adults: The mediation effects of psychosocial, cognitive influences, and the moderation effect of physiological factors

INTRODUCTION

There is a paucity of studies on e-cigarette use among adults with chronic lung disease. In the present study, we aimed to assess whether psychosocial or cognitive factors elucidate the relationship between chronic lung disease (CLD) and susceptibility to e-cigarette use and whether the relationship between CLD and e-cigarette use is conditional on the presence of respiratory symptoms.

METHODS

We recruited adults aged ≥18 years in Alabama with CLD from university medical clinics (n=140) and individuals without CLD (n=123 as a reference group). Information on sociodemographics, susceptibility to e-cigarette use, psychosocial factors, and cognitive factors were collected. Mediation analysis was used to assess whether the psychosocial factors or cognitive factors explained the association between CLD and susceptibility to using e-cigarettes, and moderation analysis was conducted to determine if respiratory factors would change the association between CLD and susceptibility to e-cigarette use.

RESULTS

Psychosocial factors (stress, depression, anxiety) and e-cigarette positive expectancy were notably high among individuals with CLD. Having CLD was associated with a lower likelihood of susceptibility to e-cigarette use. Higher levels of stress, being a smoker, boredom, taste/sensorimotor manipulation, and social facilitation were associated with higher odds of susceptibility to using e-cigarettes among individuals with CLD. Mediation analysis indicated a statistically significant indirect effect of CLD on the susceptibility to using e-cigarettes through stress and boredom reduction. We did not find a statistically significant interaction between CLD and respiratory symptoms affecting susceptibility to using e-cigarettes.

CONCLUSIONS

Individuals with CLD often exhibit stress, depression, and a positive view of e-cigarettes but are generally less inclined to use them. Stress, smoking habits, boredom, taste, and social influence can increase their susceptibility to e-cigarette use. Our findings call for further exploration to evaluate the temporal relationship between CLD status, psychosocial factors, cognitive factors, and susceptibility to using e-cigarettes.

TRIAL REGISTRATION

The study was registered on ClinicalTrials.gov, on 5 November 2019. Identifier: NCT04151784.

Electronic Cigarettes: A Pro-Con Review of the Current Literature

Electronic cigarettes (e-cigarettes, e-cigs, or electronic nicotine delivery systems) are battery-operated devices typically containing glycerol and/or propylene glycol-based solutions with varying nicotine content, known as e-liquids. Although e-cigarettes were originally developed as a potentially less harmful alternative to traditional combustible tobacco cigarette smokers, several factors have driven their popularity among smokers and nonsmokers alike, including their sleek product designs, innumerable appealing flavors, lack of combustible smoke and odor, and high potential nicotine concentrations. Furthermore, many advocates have promoted the idea that e-cigarettes are safe to use, or at least safer than conventional tobacco, despite limited longitudinal data to support these claims. Here, we examine what is known about the impacts of e-cigarette use on traditional cigarette smoking cessation, lung health, and youth and young adult tobacco product exposure. Upon review of the currently available literature, the negative effects of e-cigarette use seem to outweigh any potential benefit, because the available evidence does not confirm the use of e-cigarettes as an effective strategy for supporting traditional combustible tobacco cigarette smoking cessation, particularly given the emerging adverse effects on lung health and the potential future public health effects of e-cigarette adoption among a burgeoning new generation of tobacco product users.