Acute effects of short term use of e-cigarettes on airways physiology and respiratory symptoms in smokers with and without airways obstructive diseases and in healthy non smokers

摘要

Introduction: Although the use of e-cigarettes is increasing worldwide, their short and long-term effects remain undefined. We aimed to study the acute effect of short-term use of e-cigarettes containing nicotine on lung function and respiratory symptoms in smokers with airways obstructive disease (COPD, asthma), “healthy” smokers, and healthy never smokers. Methods: Respiratory symptoms, vital signs, exhaled NO, airways temperature, and airways resistance (Raw), specific airway conductance (sGaw) and single nitrogen breath test were assessed before and immediately after short term use of an e-cigarette containing 11 mg of nicotine in COPD, asthma, ‘’healthy” smokers, and never-smokers. The effect of nicotine-free e-cigarettes in healthy never smokers was also studied. Results: Acute cough was reported by the majority of participants. Short-term use of nicotine e-cigarettes was associated: a) with increased heart rate in all subjects except COPD, b) decreased oxygen saturation in “healthy” and COPD smokers, c) increased Raw in asthmatic, “healthy” smokers, and healthy never smokers, d) decreased sGaw in healthy subjects, and e) changed slope of phase III curve in asthmatic smokers. Short-term use of nicotine-free e-cigarette increased Raw, decreased sGaw and created a pleasant feeling. Conclusions: Short term use of e-cigarette has acute effects on airways physiology and respiratory symptoms in COPD smokers, asthmatic smokers, “healthy” smokers and healthy never smokers. E-cigarette use is associated with health effects in healthy never smokers irrespectively of nicotine concentration. More studies are needed to investigate both short and long term effects of e-cig.