Partial nicotine reduction in e-cigarettes was found to significantly increase puffing time, duration, and inhalation volume, showing a compensatory behavior that may elevate short-term toxicant exposure, according to a recent study.
The randomized crossover clinical trial—results of which were published in JAMA Network Open—assessed the impact of partial nicotine reduction on puffing behaviors among 50 adult e-cigarette users aged 21 to 35 years who preferred high-nicotine (5% concentration) salt-based e-cigarettes.
Participants completed 2 sessions using the same e-cigarette products (JUUL or NJOY) with different nicotine concentrations (5% vs 3% or 2.4%) in random order, following 12 hours of nicotine abstinence.
Of the 735 individuals initially contacted, 675 were excluded, and 10 did not finish the second session, leaving 50 participants who completed both sessions. The 50 participants had an average age of 23 years with a standard deviation of 3 years. Males comprised 56% of the group, and 46% of participants were identified as having low nicotine dependence.
Researchers found that using e-cigarettes with lower nicotine concentrations (3% or 2.4%) led to significantly higher median puffing time (1.3 vs 1.2 minutes, P = 0.02), puff duration (2.6 vs 2.4 seconds, P = 0.02), and total inhaled volume (1,990 vs 1,490 mL, P = 0.05). Additionally, the median plasma nicotine boost was significantly higher in the 5% nicotine concentration condition (0.0060 vs 0.0043 mg/L, P = 0.001).
The median increase in plasma nicotine was higher in the 5% nicotine concentration condition (0.0060 mg/L; interquartile range [IQR] = 0.0001-0.0249 mg/L) compared to the 3% or 2.4% nicotine sessions (0.0043 mg/L; IQR = 0.0008-0.0225 mg/L; P = 0.001).
Male participants had an average puff volume that was 38% greater than that of female participants (1.38 mL; 95% CI, 1.09-1.75 mL, P = 0.04). Deeper puffing was more pronounced in users with higher nicotine dependence and male users.
Full disclosures can be found in the published study.