Fourth generation e-cigarette vaping induces transient lung inflammation and gas exchange disturbances: results from two randomized clinical trials

Abstract

When heated by an electronic cigarette, propylene glycol and glycerol produce a nicotine-carrying-aerosol. This hygroscopic/hyperosmolar aerosol can deposit deep within the lung. Whether these deposits trigger local inflammation and disturb pulmonary gas exchanges is not known. The aim of this study was to assess the acute effects of high-wattage electronic cigarette vaping with or without nicotine on lung inflammation biomarkers, transcutaneous gas tensions, and pulmonary function tests in young and healthy tobacco smokers. Acute effects of vaping without nicotine on arterial blood gas tensions were also assessed in heavy smokers suspected of coronary artery disease. Using a single-blind within-subjects study design, 25 young tobacco smokers underwent three experimental sessions in random order: sham-vaping and vaping with and without nicotine at 60 W. Twenty heavy smokers were also exposed to sham-vaping ( n = 10) or vaping without nicotine ( n = 10) in an open-label, randomized parallel study. In the young tobacco smokers, compared with sham-vaping: 1) serum club cell protein-16 increased after vaping without nicotine (mean ± SE, −0.5 ± 0.2 vs. +1.1 ± 0.3 µg/l, P = 0.013) and vaping with nicotine (+1.2 ± 0.3 µg/l, P = 0.009); 2) transcutaneous oxygen tension decreased for 60 min after vaping without nicotine (nadir, −0.3 ± 1 vs. −15.3 ± 2.3 mmHg, P < 0.001) and for 80-min after vaping with nicotine (nadir, −19.6 ± 2.8 mmHg, P < 0.001). Compared with sham vaping, vaping without nicotine decreased arterial oxygen tension for 5 min in heavy-smoking patients (+5.4 ± 3.3 vs. −5.4 ± 1.9 mmHg, P = 0.012). Acute vaping of propylene glycol/glycerol aerosol at high wattage with or without nicotine induces airway epithelial injury and sustained decrement in transcutaneous oxygen tension in young tobacco smokers. Intense vaping conditions also transiently impair arterial oxygen tension in heavy smokers.

Dysregulated repair and inflammatory responses by e‐cigarette‐derived inhaled nicotine and humectant propylene glycol in a sex‐dependent manner in mouse lung

“…Here, for the first time, we report that acute exposure to PG‐containing e‐cig aerosol alone can induce oxidative stress in the lung. Supporting this, vaping without nicotine has been previously shown to result in transient lung inflammation, and gas exchange and pulmonary function abnormalities . This work suggested that acute vaping of PG/VG aerosol at high wattage with or without nicotine can induce airway epithelial injury and sustained decrement in transcutaneous oxygen tension in young tobacco‐smokers.…”

“…Supporting this, vaping without nicotine has been previously shown to result in transient lung inflammation, and gas exchange and pulmonary function abnormalities. 31 This work suggested that acute vaping of PG/VG aerosol at high wattage with or without nicotine can induce airway epithelial injury and sustained decrement in transcutaneous oxygen tension in young tobacco-smokers. This highlights that some of the lung effects, which we have seen may be directly related to PG/VG aerosols without nicotine.…”

Application of a multi-layer systems toxicology framework for in vitro assessment of the biological effects of Classic Tobacco e-liquid and its corresponding aerosol using an e-cigarette device with MESH™ technology

“…Furthermore, to investigate whether the increased cytotoxicity was influenced by hyperosmolarity, which was reported previously for PG and G (Chaumont et al 2019;Gonzalez-Suarez et al 2017), we measured the osmolarity of the e-liquids. We found that the increased cytotoxicity associated with MESH Classic Tobacco and Base e-liquids was directly correlated with the osmolarity (Supplementary Fig.…”

Prevalence of Electronic Cigarette Use and Its Determinants among 13-to-15-Year-Old Students in Greece: Results from the 2013 Global Youth Tobacco Survey (GYTS)

“…Criticism of e-cigarettes also concentrates on the fact that they damage cells, they increase the risk of chronic diseases, they increase the risk of smoking and they generally contain harmful chemicals [23]. The studies on which such criticism relies often do not compare the harm of e-cigarettes to tobacco smoke [24] or, as has been mentioned previously, rely on cross-sectional analyses [25], which cannot support causal inferences. However, talking in general of "harm" and "risk" is not constructive.…”