Commercially available since 2007, e-cigarettes are a popular electronic delivery device of ever-growing complexity. Given their increasing use by ex-smokers, smokers and never-smokers, it is important to evaluate evidence of their potential pulmonary effects and predict effects of long-term use, since there has been insufficient time to study a chronic user cohort. It is crucial to evaluate indicators of harm seen in cigarette use, and those potentially unique to e-cigarette exposure. Evaluation must also account for the vast variation in e-cigarette devices (now including at least five generations of devices) and exposure methods used in vivo and in vitro. Thus far, short-term use cohort studies, combined with in vivo and in vitro models, have been used to probe for the effects of e-cigarette exposure. The effects and mechanisms identified, including dysregulated inflammation and decreased pathogen resistance, show concerning overlaps with the established effects of cigarette smoke exposure. Additionally, research has identified a signature of dysregulated lipid processing, which is unique to e-cigarette exposure. This review will evaluate the evidence of pulmonary effects of, and driving mechanisms behind, e-cigarette exposure, which have been highlighted in emerging literature, and highlight the gaps in current knowledge. Such a summary allows understanding of the ongoing debate into e-cigarette regulation, as well as prediction and potential mitigation of future problems surrounding e-cigarette use.
|Number of pages||16|
|Journal||European Respiratory Review|
|Early online date||12 Jan 2022|
|Publication status||Published - 31 Mar 2022|
Bibliographical noteFunding Information:
Support statement: supported by the Medical Research Council (grant: MR/L002736/1) and the Wellcome Trust (grant: 2Z0108/Z/30/Z). Funding information for this article has been deposited with the Crossref Funder Registry.
© The authors 2022.