Evidence for harm reduction in COPD smokers who switch to electronic cigarettes

Background: Electronic cigarettes (ECs) are battery-operated devices designed to vaporise nicotine, which may help smokers quitting or reducing their tobacco consumption. There is a lack of data on the health effects of EC use among smokers with COPD and whether regular use results in improvement in subjective and objective COPD outcomes. We investigated long-term changes in objective and subjective respiratory outcomes in smokers with a diagnosis of COPD who quit or reduced substantially their tobacco consumption by supplementing with or converting only to ECs use. Methods: We conducted a retrospective chart review of patients with COPD to identify those reporting regular daily use of ECs on at least two follow-up visits at 12-(F/up1) and 24-months (F/up2). Regularly smoking COPD patients were included as a reference group. Results: A marked reduction in cigarette consumption was observed in ECs users. A significant reduction in COPD exacerbations was reported in the COPD EC user group, their mean (+/- SD) decreasing from 2.3 (+/- 1) at baseline to 1.8 (+/- 1; p = 0.002) and 1.4 (+/- 0.9; p < 0.001) at F/up1 and F/up2 respectively. A significant reduction in COPD exacerbations was also observed in ECs users who also smoked conventional cigarettes (i. e. 'dual users'). COPD symptoms and ability to perform physical activities improved statistically in the EC group at both visits, with no change in the control group. Conclusions: These findings suggest that ECs use may aid smokers with COPD reduce their cigarette consumption or remain abstinent, which results in marked improvements in annual exacerbation rate as well as subjective and objective COPD outcomes.