Preliminary results of an examination of electronic cigarette user puff topography: the effect of a mouthpiece-based topography measurement device on plasma nicotine and subjective effects

Abstract

Introduction: Electronic cigarettes (ECIGs) heat a nicotine-containing solution; the resulting aerosol is inhaled by the user. Nicotine delivery may be affected by users' puffing behavior (puff topography), and little is known about the puff topography of ECIG users. Puff topography can be measured using mouthpiece-based computerized systems. However, the extent to which a mouthpiece influences nicotine delivery and subjective effects in ECIG users is unknown.

Methods: Plasma nicotine concentration, heart rate, and subjective effects were measured in 13 experienced ECIG users who used their preferred ECIG and liquid (≥ 12 mg/ml nicotine) during 2 sessions (with or without a mouthpiece). In both sessions, participants completed an ECIG use session in which they were instructed to take 10 puffs with 30-second inter-puff intervals. Puff topography was recorded in the mouthpiece condition.

Results: Almost all measures of the effects of ECIG use were independent of topography measurement. Collapsed across session, mean plasma nicotine concentration increased by 16.8 ng/ml, and mean heart rate increased by 8.5 bpm (ps < .05). Withdrawal symptoms decreased significantly after ECIG use. Participants reported that the mouthpiece affected awareness and made ECIG use more difficult. Relative to previously reported data for tobacco cigarette smokers using similar topography measurement equipment, ECIG-using participants took larger and longer puffs with lower flow rates.

Conclusions: In experienced ECIG users, measuring ECIG topography did not influence ECIG-associated nicotine delivery or most measures of withdrawal suppression. Topography measurement systems will need to account for the low flow rates observed for ECIG users.

Figure 1.

Mean plasma nicotine concentrations (±SEM) for 13 participants who completed a 10-puff ECIG use bout (30 s interpuff interval) in two conditions: with no topography mouthpiece and with a topography mouthpiece. Filled symbols indicate a significant difference from before ECIG use (−30; the first value). All ps < .05; Tukey’s HSD.

Figure 2.

Mean ratings (±SEM) for four visual analog scale items from 13 experienced ECIG users using their preferred device and strength/flavor in two sessions that differed by whether a mouthpiece-based topography system was attached to the ECIG. “Urge to Use an e-cigarette” (top left) and “Anxious” (top right) were from the Hughes-Hatsukami withdrawal scale. “Light-headed” (bottom left) was from the Direct Effects of Nicotine scale and “Calm” (bottom right) was from the Direct Effects of ECIG Use scale. Filled symbols indicate a significant difference from before ECIG use (i.e., −30). All ps < .05; Tukey’s HSD.