First versus second generation electronic cigarettes: predictors of choice and effects on urge to smoke and withdrawal symptoms

Aims: To 1) estimate predictors of first vs. second generation electronic cigarette (e-cigarette) choice; 2) determine whether a second generation device was i) superior for reducing urge to smoke and withdrawal symptoms (WS) and ii) associated with enhanced positive subjective effects. Design: Mixed effects experimental design. Phase 1: reason for e-cigarette choice was assessed via questionnaire. Phase 2: participants were randomly allocated to first or second generation e-cigarette condition. Urge to smoke and WS were measured before, and 10mins after, taking 10 e-cigarette puffs. Setting: University of East London, UK. Participants: 97 smokers (mean age 26; SD 8.7; 54% female) Measurements: Single item urge to smoke scale to assess craving; Mood and Physical Symptoms Scale (MPSS) to assess WS. Subjective effects included: satisfaction, hit, ‘felt like smoking’ and ‘would use to stop smoking’ (Yes vs. No response). Findings: Equal numbers chose each device but none of the predictor variables (gender, age, tobacco dependence, previous e-cigarette use) accounted for choice. Only baseline urge to smoke/WS predicted urge to smoke/WS 10 minutes after use (B=0.38; P<0.001 and B=0.53; P<0.001). E-cigarette device was not a significant predictor. Those using the second generation device were more likely to report satisfaction and use in a quit attempt (χ2=12.10, P=0.001 and χ2=5.53, P=0.02). Conclusions: First and second generation e-cigarettes appear to be similarly effective in reducing urge to smoke and WS during abstinence but second generation devices appear to be more satisfying to users.