Passive exposure to e-cigarette vaping linked to acute health effects in COPD
In patients with chronic obstructive pulmonary disease (COPD), passive exposure to vape from e-cigarettes has been shown to be potentially harmful by exerting acute small inflammatory responses in the lungs and blood, as well as irritation of the throat. The results of the analysis have been published in the European Clinical Respiratory Journal.
Researchers sought to explore the local and systemic effects of short-term passive exposure to vaping in people with mild to moderate COPD. A randomized, controlled, double-blind, crossover study on the subject was conducted in Denmark. All participants were subjected to 2 exposure sessions. Each of the sessions lasted 4 hours, containing either air mixed with aerosol from e-cigarette users or clean, filtered air, and took place 2 weeks apart. , in order to eliminate any residual effect. Aside from the air quality, the clean filtered air and e-cigarette vape sessions were identical. Exposure sessions took place in an exposure chamber, while exposure generation occurred in an adjacent chamber. All particles were measured using an ultrafine particle counter and a scanning mobility particle sizer.
All participants recruited were non-smokers with mild or moderate COPD. Their diagnosis of COPD was established by symptoms and spirometry (using forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] below the lower limit of normal, Medical Research Council [MRC] score ≥ 2 and COPD assessment test score ≥ 10). All patients who were taking long-acting bronchodilators and inhaled corticosteroids were switched to short-acting bronchodilators 1 week prior to study entry. All participants had to be free of any signs of infection or respiratory tract symptoms for ≥ 1 week and had not taken any medication for ≥ 48 hours.
Primary outcomes of interest included surfactant protein A (SP-A) and expired air albumin. Secondary study outcomes included spirometry, fractionated exhaled nitric oxide, plasma protein, and self-reported symptoms. A total of 16 people (6 women and 10 men) participated in the study. The average age of the participants was 67.6 years.
Peak particle counts on days of vaping exposure ranged from approximately 30-40 nm. Although minor, another spike was seen for larger particles (i.e. 200-500nm), which coincided with vapers’ reports of coil overheating. Thus, these particles could come from combustion. When the particle size was about 300-500 nm, the particle mass peaked.
Study results showed that exhaled SP-A was negatively affected by vaping exposure, with levels of several plasma proteins increasing significantly. Throat irritation was greater during passive vape exposure, while FEV11 and FVC values decreased, but not significantly.
Limitations of the study included low power due to few participants, and additionally, not all participants were able to pass all health examinations, resulting in missing data.
The investigators concluded that further studies of exposure to passive vaping in susceptible subgroups of patients are warranted, as well as future studies of people chronically exposed to passive vaping, as such studies are currently almost non-existent.
Rosenkilde Laursen K, Bønløkke JH, et al. An RCT of acute health effects in patients with COPD after passive exposure to vaping from e-cigarettes. Eur Clin Respir J. 2020;8(1):1861580. doi:10.1080/20018525.2020.1861580