Vaping high nicotine concentrations may lead to cigarette smoking in adolescents
In adolescents, the use of e-cigarettes with higher nicotine levels appears to lead to subsequent spikes in cigarette and e-cigarette smoking, a recent study has shown.
“Youths who vaped e-cigarettes with higher nicotine concentrations at baseline were more likely to progress to higher frequency and intensity levels of vaping and smoking at 6-month follow-up after adjusting for baseline e-cigarette and combustible cigarette use,” said the researchers.
The preliminary study included 181 10th graders (mean age 16.1±0.4 years; 47.0 percent female) who were followed for 6 months and surveyed for baseline and follow-up 30-day smoking and vaping habits. Main study outcomes were the frequency and intensity of combustible and e-cigarette smoking.
At baseline, 35.0 percent (n=63) reported smoking a cigarette and 59.7 percent (n=108) vaped a solution with nicotine within the past 30 days. Of those who used e-cigarettes, 28.7 percent (n=52) vaped low nicotine concentrations, 19.3 percent (n=35) vaped medium concentrations and 11.6 percent (n=21) vaped high nicotine concentrations. [JAMA Pediatr 2017;doi:10.1001/jamapediatrics.2017.3209]
Adjusted multinomial regression models showed that with every increase in nicotine consumption level at baseline (ie, none to low, low to medium, medium to high), the odds of reporting frequent smoking, compared with no smoking, within the last 30 days also increased (odds ratio [OR], 2.26; 95 percent CI, 1.28 to 3.98).
In contrast, high baseline nicotine consumption was not associated with increased risk of infrequent smoking within the last 30 days (OR, 1.01; 0.54 to 1.89).
Similarly, adjusted models showed an increase in vaping frequency associated with increasing baseline nicotine concentrations (OR, 1.65; 1.09 to 2.51). Adjustments were made for sex, baseline peer smoking and vaping and other demographic factors.
In terms of smoking intensity, those who vaped high nicotine concentrations at baseline smoked significantly more cigarettes per day during the 6-month follow-up (rate ratio [RR], 7.03; 6.11 to 7.95). In contrast, those who smoked low (RR, 1.65; 0.73 to 2.57) and medium (RR, 1.63; 0.77 to 2.49) baseline concentrations did not experience significantly elevated intensities at follow-up.
According to the researchers, early exposure to nicotine may result in dependence and high tolerance which, in turn, lead to higher consumption levels.
“Although biologically plausible, whether nicotine-induced tolerance, dependence, neural dysregulation, or other cognitive (eg, expectancies) and social (eg, peer affiliations) factors explain the observed associations warrants further investigation,” they said.
“[T]he results of this study provide preliminary evidence that regulatory policies addressing nicotine concentration levels in e-cigarette products used by adolescents may affect progression of combustible cigarette and e-cigarette use among youths,” they added.