A randomised, crossover study on an electronic vapour product, a nicotine inhalator and a conventional cigarette. Part B: Safety and subjective effects

Abstract

An Electronic Vapour Product (EVP) has been evaluated for short-term safety parameters and subjective effects in a 2-part study, in smokers. Part 1 compared the EVP with unflavoured (UF) and flavoured (FL) e-liquid at 2.0% nicotine to a conventional cigarette (CC; JPS Silver King Size, 0.6 mg) and a licensed nicotine inhalator (Nicorette(®), 15 mg). Part 2 assessed the effect of increasing concentrations of nicotine in the e-liquid used with the EVP (0%, 0.4%, 0.9%, 2.0%). The study was designed as a randomised, controlled, crossover trial. Outcomes included adverse events (AEs), vital signs, exhaled carbon monoxide (CO), clinical laboratory parameters, smoking urges and withdrawal symptoms. In both study parts, only mild non-serious AEs were reported. No major differences were observed in AEs between the EVPs and Nicorette(®). Exhaled CO levels only increased for CC. All products appeared to decrease smoking urges and nicotine withdrawal symptom scores to a similar extent. The EVP had a similar short-term safety profile to Nicorette(®) and relieved smoking urges and nicotine withdrawal symptoms to a similar extent as Nicorette(®) and CC. Unlike nicotine replacement therapies, the EVP may offer an alternative for those finding it difficult to quit the behavioural and sensorial aspects of smoking.

Overview of Electronic Nicotine Delivery Systems: A Systematic Review

“…Laboratory studies find modest increases in nicotine biomarkers after vaping. 169,195,197,203,206,209–211,215,222,223,232,233,239,246,248,264,271,284,300 Vaping has no or minimal impact on other physiologic measures (i.e., exhaled carbon monoxide, complete blood count, body weight), 142,202,203,230,237,239,242,257,265,272,274,276,282,285,292,303 with improvements in outcomes seen for smokers switching to ENDS, such as reduced blood pressure, improved lung function, and improved disease symptoms (i.e., asthma and chronic obstructive pulmonary disease). 214,230,273,287 Some studies have examined cardiovascular measures associated with vaping, 195,197,209,222,223,226,232,246,248,257,273,300,301 with the majority finding an increase in heart rate, 195,223,232,246,248,300 but three finding no change after use.…”

“…258 Other studies report the most common adverse events associated with vaping as mouth and throat irritation, nausea, headache, and dry cough. 193,199,202,203,214,217,232,240,249,264,265,288,303,304,320 From 2012 to 2015, there were 92 reported overheating/fire/explosion events in the U.S., and about half resulted in injuries (i.e., thermal burns, lacerations, or smoke inhalation). 291 …”

Electronic cigarettes—A review of the physiological health effects

“…The most common acute adverse effects due to EC use were irritation of the respiratory tract (including the mouth and throat), dry throat, cough, and cough reflex suppression (Nides et al 2014;D'Ruiz et al 2015;Salturk et al 2015;Dicpinigaitis et al 2016a;Walele et al 2016). These effects are probably due to the propylene glycol discussed earlier, which is a component of the EC liquid and is a known respiratory irritant.…”

“…Szołtysek-Bołdys et al (2014) found that the acute use of ECs did not have an effect on arterial stiffness, but the acute use of CCs did. Similarly, Walele et al (2016) found that there was no change in cardiac function, including heart rate and blood pressure, after smokers took 10 puffs from nicotine and nicotine-free ECs four times per day for 4 d. Finally, Farsalinos et al (2016a) found a beneficial effect on systolic blood pressure of switching to ECs from CCs after following 145 participants for a year. Results from these above studies should be interpreted with caution.…”

“…Among the smokers, there was also a decreased peak (highest) expiratory flow (PEF value) when air was being expelled from the lungs (Ferrari et al 2015). Walele et al (2016) found no change in pulmonary function (including in values such as the FEV1) for flavoured or unflavoured liquid or varying nicotine concentrations when 24 smokers took 10 puffs from the EC device four times per day for 4 d. Again, these different results may be due to different puffing regimes or the use of different liquids or devices that may affect lung function differently. One clinical study of 18 smoking asthmatics showed an improvement in their symptoms when they switched from CCs to ECs for a year, including a decrease in their airway hyperresponsiveness and an increase in their lung capacity (Polosa et al 2014(Polosa et al , 2016.…”