Short‐term respiratory effects of e‐cigarettes in healthy individuals and smokers with asthma

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. Results Control session revealed no significant changes. In the experimental session, immediately post‐ECS, both groups exhibited a significant increase in respiratory system total impedance at 5 Hz (Z5) (P