Tobacco Center Faculty Blog

The paper, “Potential deaths averted in USA by replacing cigarettes with e-cigarettes” by David  Levy et al. published in Tobacco Control on October 2, 2017, attracted a moderate amount of attention with its conclusion that “Compared with the Status Quo, replacement of cigarette by e-cigarette use over a 10-year period yields 6.6 million fewer premature deaths with 86.7 million fewer life years lost in the Optimistic Scenario. …  Our projections show that a strategy of replacing cigarette smoking with vaping would yield substantial life year gains, …” 
 
This is a pretty impressive result until you consider that the Optimistic Scenario is based on a series of assumptions that are of which are inconsistent with empirical evidence to date:
 

Andreas Lappas and colleagues just published “Short-term respiratory effects of e-cigarettes in healthy individuals and smokers with asthma,”  which shows that when smokers use an e-cigarette, it worsens lung function, with bigger effects in smokers who already have asthma.
 
This is an important finding because it indicates that dual use of cigarettes and e-cigarettes, by far the most common use pattern, is worse than smoking alone.
 
Here is the abstract:
 
Background and objective:  This study investigated the duration of immediate respiratory effects of e-cigarette smoking (ECS) and tested the hypothesis that ECS has more prominent effects in asthmatics compared with healthy smokers (HS).
Methods; Fifty-four smokers, 27 healthy (HS group) and 27 with intermittent asthma (mild asthma (MA) group) underwent a control session (no liquid, no resistor coil inside e-cigarette cartridge) and an experimental session of ECS using standardized puffing settings. Impulse oscillometry impedance (Z), resistance (R), reactance (X) and fractional exhaled nitric oxide (FeNO) were measured before and 0, 15 and 30 min after control and experimental sessions.