Nicotine dependence and smoking topography in tobacco-naïve users of disposable e-cigarettes: A prospective single-center, single-arm interventional study

INTRODUCTIONCurrently, e-cigarettes constitute a major product category that enjoys substantial popularity, particularly with adolescents.Literature, however, requires studies conducted with tobacco-naïve youth and hence this single-center, one-arm study, aimed at characterizing this population, their consumption patterns, and the addictive potential of e-cigarettes.METHODS Between December 2023 and August 2024, seventeen tobacco-naïve, regular e-cigarette users (>6 sessions/week) participated in this prospective single-arm interventional study at LMU University Hospital.Participants used a disposable e-cigarette ad libitum for 30 minutes during a 60 minute testing period.The results were compared with those from a previous adjacent study of occasional smokers using both a disposable e-cigarette and a combustible cigarette.We investigated nicotine dependence using two questionnaires: the Fagerström test for nicotine dependence (FTND) adapted for e-cigarettes and the Penn State Electronic Cigarette Dependence Index (PSECDI).Consumption behavior was characterized through puff topography using a smoking puff analyzer (SPA-M) and by repeated measurement of plasma nicotine concentrations. RESULTSThe mean FTND score was 3.29 (SD=2.47),corresponding to the questionnaire-defined category of moderate dependence (score 3-4).The mean PSECDI score was 7.71 (SD=3.96),corresponding to the questionnaire-defined category of low dependence (score 4-8).This suggests that regular e-cigarette use may lead to measurable nicotine dependence in a tobacco-naïve population.Ad libitum e-cigarette use was characterized by a larger time interval (seconds) between puffs (p=0.001;95% CI: 24.97-81.29)compared to disposable e-cigarette consumption within a 5-minute time period.Nevertheless, nicotine concentrations consistently increased until the 30 minutes mark, reaching a final mean of 16.74 ng/mL, which is comparable to tobacco cigarettes.CONCLUSIONS These results provide evidence that frequent e-cigarette use may induce nicotine dependence in previously tobacco-naïve individuals, highlighting the need for further characterization of this population and larger prospective studies to generate more robust evidence.