An observational human laboratory assessment of nicotine delivery, vaping topography and subjective effects of usual brand electronic cigarette use among young adults.

aimsTo measure nicotine delivery, vaping topography and subjective effects of current generations of disposable, cartridge-based and other types of electronic cigarettes (e-cigarettes) among young adults. DESIGN, SETTING,

participantsObservational, human laboratory assessment of e-cigarette use in Columbus, Ohio, USA (July 2020 to June 2021). Participants (n = 96, 60.4% female, age mean = 21.7 [standard deviation = 1.7] years, 82.4% white race) were identified via their participation in a cohort study or other convenience sampling and were 18 to 25 years old, vaped ≥4 days/week for ≥4 weeks and used other tobacco products for ≤5 days of past 30 days. Participants completed a pre-vaping questionnaire, vaped their usual brand of e-cigarette ad libitum for 30 min and completed a post-vaping questionnaire. MEASUREMENTS: Outcome variables included pre- and post-vaping measures of plasma nicotine (t = 0 and t = 30, respectively) and craving and withdrawal symptoms, as well as vaping topography (e.g. flow rate and inter-puff interval), pre-vaping expectancies and post-vaping product appeal. Variables used to characterize the sample included demographics, e-cigarette and other tobacco use history, e-cigarette dependence and e-cigarette device characteristics (e.g. device type, flavor and nicotine form).

findingsParticipants reported moderate nicotine dependence on average via the E-Cigarette Dependence Scale (mean = 6.9 [standard deviation = 4.0]). Following 30 min of ad libitum vaping, participants achieved substantial plasma nicotine boost (mean = 18.8 [standard deviation = 14.5] ng/mL), corresponding with statistically significant decreases in withdrawal symptoms measured via the Minnesota Nicotine Withdrawal Scale (pre-vaping mean = 9.0 [standard deviation = 5.1], post-vaping mean = 4.3 [standard deviation = 3.9]; P-value <0.0001). Pre-vaping, participants reported moderate vaping expectancies (e.g. mean = 2.5 [standard deviation = 1.0] on a scale from 0 to 4 for smell and taste expectancies); post-vaping, participants reported high satisfaction (mean = 4.6 [standard deviation = 1.2] on a scale from 1 to 7) and moderate reward (mean = 2.9 [standard deviation = 1.2]) and respiratory sensations (mean = 3.7 [standard deviation = 1.6]). Nearly half of participants (47.9%) used disposable e-cigarettes, and most used a mint/menthol or fruit flavored (99.0%) and nicotine salt (98.9%) e-liquid.

conclusionsAmong young adults in the United States, the latest generations of e-cigarettes appear to deliver large quantities of nicotine (similar to cigarettes) and significantly relieve withdrawal symptoms, and they are appealing.