Related Experiment Video
Updated: Jul 1, 2025

Comparing the Effects of Electronic Cigarette Vapor and Cigarette Smoke in a Novel In Vivo Exposure System
Published on: May 24, 2017
Exhaled nitric oxide levels in COPD patients who use electronic cigarettes
Andrew Higham1, Augusta Beech2, Dave Singh2
1Division of Immunology, Immunity to Infection and Respiratory Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester and Manchester University NHS Foundation Trust, Manchester, UK.
Abstract:
Emerging data from clinical studies have shown pro-inflammatory effects associated with e-cigarette use. Fractional exhaled nitric oxide (FeNO) is a biomarker of pulmonary type 2 (T2) inflammation. The effect of chronic e-cigarette use on FeNO is unclear. The aim of this study was to compare FeNO levels in COPD ex-smokers who use e-cigarettes (COPDE + e-cig) to COPDE ex-smokers (COPDE) and COPD current smokers (COPDS). FeNO levels were significantly higher in COPDE + e-cig (median 16.2 ppb) and COPDE (median 18.0 ppb) compared to COPDS (median 7.6 ppb) (p = 0.0003 and p < 0.0001 respectively). There was no difference in FeNO levels between COPDE + e-cig compared to COPDE (p > 0.9). The importance of our results is that electronic cigarette use does not alter the interpretation of FeNO results, and so does not interfere with the use of FeNO as a practical biomarker of T2 inflammation, unlike current cigarette smoking in COPD. Whilst the effect of electronic cigarette use on FeNO levels is not the same as cigarette smoke, this cannot be taken as evidence that electronic cigarettes are harmless. These differential pulmonary effects can be attributed to differences in the chemical composition of the two products.
Related Concept Videos
Chronic Obstructive Pulmonary Disease-I: Introduction
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
COPD: Management Using Bronchodilators and Corticosteroids

