Comparison of e-cigarette use characteristics between exclusive e-cigarette users and dual e-cigarette and conventional cigarette users: an on-line survey in France.

Abstract

Completely substituting e-cigarettes (EC) for combustible tobacco cigarettes reduces exposure to toxicants and carcinogens. However, a large proportion of EC users (dual users) continue to smoke conventional cigarettes. This study aimed to compare estimated nicotine intake and e-cigarette use characteristics between exclusive EC users and dual users. Web-based anonymous cross-sectional survey. France. A total of 3189 adults, current users of electronic cigarettes (EC). Data collection between 4October 2014 and 11November 2014. Primary outcome: estimated nicotine intake per day (mg) from participants' reports. duration, frequency of EC use and nicotine content of e-liquids used/day. Dual use was defined as using at least one cigarette per day while also using EC. A total of 2836 respondents reported exclusive EC use and 353 reported being dual users. Backward stepwise logistic regression showed that dual users had higher estimated combined daily nicotine intake from e-liquids and cigarettes [estimate: 2.14, standard error (SE)=0.26, adjusted odds ratio (aOR)=8.48, 95% confidence interval (CI)=5.11-14.09, P<0.001], but lower daily nicotine intake from EC (estimate: -2.14, SE=0.26, aOR=0.12, CI=0.07-0.196, P<0.001) and reported fewer months of EC use (estimate: -0.31, SE=0.14, aOR=0.73, CI=0.56-0.95, P=0.022) compared with exclusive EC users. Dual e-cigarette users in France may have higher nicotine intake overall than exclusive e-cigarette users, but they may take in less nicotine from their e-cigarettes.