Changes in puffing behavior and lung functions among smokers who switched to electronic cigarettes for two weeks

Electronic cigarettes deliver nicotine without many dangerous combustion toxicants found in tobacco smoke. Recent Data shows that nicotine intake from e-cigarette increases with experience. This would suggest that smokers adapt and learn how to use e-cigarette over the time. Thus, it is important to understand how smokers change their puffing behavior after switching to e-cigarettes for development of strategies for smoking cessation.

The aim of the study was to assess the changes in puffing behavior and lung functions after switching to e-cigarette from conventional cigarette among regular smokers.

Twenty smokers naïve to e-cigarette participated in a study. They were asked to substitute tobacco cigarettes with first generation e-cigarettes for two weeks. Participants participated in three experimental sessions in a lab: at the first use of the product, and after 7 and 14 days. During each session we measured lung functions and puffing topography. Assessment of puffing topography included number of puffs, puff volume, intervals between puffs, and average puff flow rate. We also measured lung functions which included EVC, FEV1, FVC, and PEV. We tested changes in puffing topography and lung functions using repeated measures ANOVA.

We found that after 7 days of using e-cigarettes smokers significantly increased the puff duration on e-cigarettes from 2.3 to 3.3 sec (p<0.05). The puff flow rate decreased from 30.8 to 24.4ml/sec after 7 days of using e-cigarettes (p<0.05). We found no changes in numbers of puffs, puff volume, duration of puff intervals, and lung functions between baseline and follow-up sessions (p>0.05). 

Our data showed that smokers modify their puffing behavior after switching from tobacco to electronic cigarettes. Potential reason for changing puffing behavior is to compensate for poorer nicotine delivery from e-cigarettes. Such compensation mechanism may be driven by smokers’ desire to inhale similar doses of nicotine as they got from tobacco cigarette.