Are Electronic Nicotine Delivery Systems Helping Cigarette Smokers Quit? Evidence from a Prospective Cohort Study of US Adult Smokers, 2015–2016.

At baseline, 27.1% (n = 248) of smokers who completed the follow-up survey reported using ENDS. 90% of dual users were still smoking after 12-months of follow-up. 53.5% remained dual users at follow-up, and 37.4% were still smoking but had discontinued ENDS. Overall, 9.2% of the baseline ENDS users reported that they quit smoking at follow-up. No significant differences were detected at follow-up for number of cigarettes smoked per day (CPD) between ENDS users and non-users. Odds of making a subsequent smoking quit attempt over the next 12 months did not statistically significantly differ between baseline ENDS users and non-users (53.7% vs. 48.6%; aOR = 0.99; 95% CI: 0.56-1.77). Smokers who reported any ENDS use during the study period had 1.92 times higher odds of making a quit attempt compared to those who never reported ENDS use (58.5% vs. 44.4%; aOR = 1.92; 95% CI: 1.15-3.19). However, attempts to quit did not correlate with higher likelihood of cessation success: baseline ENDS users had 70% lower odds of cessation than baseline non-users (aOR = 0.30; 95% CI: 0.13-0.72). A similar trend was seen for smokers who reported any ENDS use during the study, who had 75% lower odds of quitting smoking than non ENDS-users (aOR = 0.25; 95% CI: 0.11-0.57). ENDS users who reported use at baseline and follow-up had the lowest adjusted odds of quitting compared to nonusers (aOR = 0.05; 95% CI: 0.01-0.18). When analyzing ENDS use frequency groups separately, non-daily ENDS users had 2.14 higher adjusted odds of making a quit attempt than non-users (59.7% vs. 44.2%; aOR = 2.14; 95% CI: 1.24-3.69). However, daily and non-daily ENDS users had significantly lower odds of quitting smoking (aOR = 0.27; 95% CI: 0.11-0.64; aOR = 0.17; 95% CI: 0.04-0.82). Flavorings and Quit Attempts/Cessation Compared to those using tobacco/unflavored e-liquid, odds of cessation were 3.4 times higher for menthol/wintergreen/mint users and 2.0 times higher for other flavor users; however, these odds were not statistically significant (95% CIs: 0.48-24.1 and 0.38-10.2, respectively). Among baseline daily smokers, both menthol/wintergreen/mint users and other flavor users were significantly more likely to report a quit attempt (aOR = 6.02; 95% CI: 2.28-15.91; aOR = 2.36; 95% CI: 1.13-4.96) than nonusers of ENDS, and menthol/wintergreen/mint users were more likely to report a quit attempt than tobacco/unflavored users (p < 0.05). However, those using tobacco-flavored/unflavored and other flavors (e.g. fruit, dessert, spice) had statistically significantly lower odds of quitting than non-users (aOR = 0.11; 95% CI: 0.02-0.50; aOR = 0.22; 95% CI: 0.08-0.59).

Weaver, S. R., Huang, J., Pechacek, T. F., Heath, J. W., Ashley, D. L., & Eriksen, M. P. (2018). Are Electronic Nicotine Delivery Systems Helping Cigarette Smokers Quit? Evidence from a Prospective Cohort Study of US Adult Smokers, 2015–2016. PLoS One, 13(7), e0198047.