Correlates of using E-cigarettes with high nicotine concentrations among U.S. adults who exclusively vape E-cigarettes or dual use with cigarettes.

Background: Identifying the correlates of using e-cigarettes with high nicotine concentrations in exclusive and dual-using vapers can elucidate which subpopulations might be most impacted by e-cigarette regulatory activities related to nicotine concentration.

Methods: Data are drawn from Wave 5 (December 2018-November 2019) of the Population Assessment of Tobacco and Health (PATH) study. Self-reported nicotine concentration was grouped as high (5.0 %+), moderate (1.8-4.9 %), low (0.1-1.7 %), 0 %, and "I don't know." Multivariable logistic regressions estimated associations of sociodemographic factors, tobacco use status, and e-cigarette use patterns of high nicotine concentration vs. other nicotine levels, stratified by current exclusive e-cigarette use and dual use of e-cigarettes and cigarettes.

Results: In the study samples (exclusive e-cigarette use [n = 1,755], dual-use [n = 1,200]), higher proportions of exclusive e-cigarette users reported using high nicotine concentrations than dual users (18.3 % vs. 8.6 %). Among exclusive e-cigarette users, never vs. former smokers and daily (vs. someday) e-cigarette users were more likely to use high vs. low nicotine. In both exclusive and dual users, younger (vs. older) adults were more likely to report using high nicotine concentration e-cigarettes than most other nicotine levels. Current dual users who did vs. did not report using e-cigarettes to quit smoking had higher odds of using high vs. 0 % nicotine concentrations.

Conclusions: High-nicotine e-cigarette use might be elevated in subpopulations that face greater risks for vaping (e.g., never smokers, young adults) than groups who benefit from the potential harm reduction. Regulatory restrictions on high-nicotine products may selectively affect some subgroups adversely impacted by vaping.