Disposable E-Cigarette Use and Subsequent Use Patterns in Adolescents and Young Adults.

BACKGROUND AND OBJECTIVES:Disposable electronic cigarettes (e-cigarettes) are widely used by adolescents and young adults (AYAs). Whether using disposable devices is associated with future e-cigarette use patterns is unknown but important for informing e-cigarette regulation. METHODS:Prospective longitudinal study combining data from adolescent (14-17 years) and young adult (21-24 years) cohorts from Southern California surveyed at baseline and approximately 8-month follow-up during 2021 to 2022. The analyses included AYAs who used e-cigarettes in the past 30 days at baseline and had exposure and outcome data (N = 403; adolescent n = 124, young adult n = 279). RESULTS:In the pooled sample of AYAs who used e-cigarettes at baseline (57.2% cis-gender female, 56.2% Hispanic), 278 (69.0%) reported past 30-day disposable e-cigarette use, and 125 (31.0%) used only nondisposable e-cigarettes. Baseline use of disposable (versus only nondisposable) devices was associated with higher odds of continued e-cigarette use (adjusted odds ratio = 1.92; 95% confidence interval = 1.09-3.42) and a greater number of times used e-cigarettes per day at follow-up (adjusted incidence rate ratio = 1.29; 95% confidence interval = 1.02-1.63). In supplemental analyses, disposable e-cigarette use was associated with greater odds of no changes (versus reductions) in e-cigarette use frequency and puffs per episode from baseline to follow-up but was not associated with increases in use frequency and intensity. No differences in e-cigarette use outcomes were found between those with poly-device (disposable and nondisposable) versus only disposable device use. CONCLUSIONS:Use of disposable e-cigarette devices among AYAs may be associated with higher risks for persistent e-cigarette use patterns, which should be considered in tobacco product regulation designed to protect AYAs.