A recent study published in npj Primary Care Respiratory Medicine indicated that although vaping increases airway resistance, it doesn’t impact lung function.

Study: A scientific review of the results of e-cigarette use on lung function. Image Credit: LezinAV/Shutterstock

Background

In recent times, electronic cigarette use (or vaping)––which was thought to be a safer alternative to traditional cigarettes––has had a huge effect on the tobacco industry. Nevertheless, evidence depicts the harmful effects of vaping on the respiratory system.

In e-cigarettes, nicotine combustion is replaced by the electronic heating of a liquid. Some manufacturers claim that e-cigarettes have fewer opposed effects on the respiratory system than smoking tobacco. 

E-cigarettes have been tried as an alternative choice to smoking tobacco for addiction treatment – as an aid to quitting tobacco smoking. Previously believed to be less hazardous to health than traditional cigarettes, the negative impact of vaping on the lungs is now common knowledge. 

The emergence of E-Cigarette and Vaping-Associated Lung Illness (EVALI) has raised concerns concerning the short-term respiratory effects of vaping, particularly when cannabis or tetrahydrocannabinol (THC)-containing products are utilized in e-cigarettes. Considering this evidence, the security of e-cigarette use and its efficacy remain disputed. Due to this fact, an intensive study was undertaken to analyze the results of vaping on lung function. 

The study

This systematic review entailed a comprehensive evaluation of how vaping affects pulmonary function. The goal of this review was to acquire information regarding the short-term effects of vaping and Vaping-Associated Lung Illness (EVALI) – to find out the security of vaping on short- and long-term use.

A study protocol was prepared and recorded within the PROSPERO database of systematic reviews. The systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations.

Using Ovid, Cochrane, Web of Science Core, and the CENTRAL database, the researchers searched EMBASE, PsycINFO, and MEDLINE from 2004-2021 – to discover 8,856 potentially relevant studies. 

Overall, 273 participants were included within the eight chosen studies. Seven studies examined the immediate effects of vaping, while just one examined the long-term impact.

The findings

In keeping with the literature review, only eight small-scale studies addressed this topic; amongst these, one study examined the long-span outcomes (3.5 years). These studies revealed that vaping was not related to any acute health-related changes. 

However, two studies disclosed that e-cigarettes might accentuate airway resistance and conductance across diverse demographic subgroups. Resulting from the limited variety of studies available on this topic and since most concentrate on the acute effects of vaping, these findings are suggestive but not conclusive, and further research is crucial. 

There have been a couple of other limitations to the interpretability of the outcomes – three of the included studies had an unknown risk of bias, 4 had a moderate risk of bias, and one had a high bias risk.

Moreover, resulting from the information heterogeneity, this review didn’t undertake subgroup analyses or a meta-analysis. This search incorporated only a small variety of studies owing to the differences amongst study designs, definitions of e-cigarettes, and the participants’ smoking status. 

In keeping with some studies, the term “non-vapers” includes each traditional smokers and non-smokers – this led to inconsistent data and non-differentiation of the participants based on their conventional smoking status. 

The outcomes depicted no effect of vaping on the forced expiratory volume in a single second (FEV1), forced vital capability (FVC), and the FEV1/FVC ratio.

Some studies also employed a mock vaping session wherein either an e-cigarette without e-liquid or second-hand smoke was used. Of note, a lot of the studies were conducted on smokers alone, with out a comparison group of nonsmokers. 

It could be helpful to conduct future research on subgroups based on the extent of smoking or vaping to enable a more accurate quantitative evaluation.