Initial e-cigarette flavoring and nicotine exposure and e-cigarette uptake among adolescents.

Abstract

E-cigarettes are the most prevalent tobacco product used by adolescents. We sought to determine whether the presence of flavoring and/or the presence of nicotine at the first e-cigarette exposure predicted progression to current e-cigarette use (use in past 30 days) as well as escalation in use (number of days in the past 30 days) among adolescents. Adolescents from public high schools outside of Philadelphia, PA completed in-classroom surveys at baseline (9^th grade) and at 6-month intervals for the following 18 months (fall 2018, beginning of 11^th grade). Adolescents who reported ever having used e-cigarettes at baseline (N = 354) comprised the analytical sample. We employed a two-part Latent Growth Curve Model including flavor, nicotine, and other covariates. Initial use of a flavored (vs unflavored) e-cigarette was associated with progression to current e-cigarette use (β = 0.54, z = 2.09, p = 0.04) and escalation in the number of days of e-cigarette use (β = 0.35, z = 2.58, p = 0.01) across the following 18 months. Initial use of an e-cigarette with nicotine (vs without nicotine) was associated with a greater number of days of e-cigarette use at baseline (β = 0.49, z = 2.16, p = 0.03). The findings underscore the risk that flavoring and nicotine pose for progression beyond initial e-cigarette use. Regulations addressing flavoring and nicotine in e-cigarettes have the potential to reduce the number of adolescents who become current as well as frequent e-cigarette users.