Nicotine Intake, Dependence, and Characteristics of Electronic Cigarette and Dual Users

Objectives: We examined nicotine exposure, level of dependence, reasons for vaping, use patterns, and device characteristics to increase understanding of electronic cigarette and dual tobacco cigarette (TC) users and to help inform potential health benefits and risks. Methods: We had 68 exclusive electronic cigarette (EEC) and 100 dual users (DU) complete questionnaires and provide saliva for cotinine measurement. Results: The mean age of participants was 34 years and 65% were male. Among DUs, 31 were light DUs (<= 5 cigarettes per day (CPD)) and 69 were heavy DUs (>5 CPD). Cotinine levels were not significantly different for EEC users and DUs, although heavy DUs had significantly lower cotinine than light DUs. EEC users had a shorter time to first vape than DUs. Compared to DUs, EEC users were more likely to vape daily, to vape to reduce health risk from tobacco cigarettes (amongst other reasons), to use a second- or third-generation device and to use lower nicotine concentration e-liquids. Conclusions: Dual and EEC users had similar daily nicotine intake, and DUs' time to first cigarette was similar with EEC users' time to first vape, suggesting a similar degree of dependence.