Associations between e-cigarette policies and adolescent use and access to e-cigarettes.

Background: Tobacco control policies have been adapted to address rising levels of adolescent e-cigarette use. Despite new restrictions, adolescents are continuing to access e-cigarettes. Methods: We linked 2015-2019 Youth Risk Behavior Survey data on 503,154 14-18-year-olds from 40 states with state-level e-cigarette minimum legal sales age (MLSA) laws, taxes, and smoke-free legislation. Using two-way fixed effects probit regression models, we first examined the associations between these statewide e-cigarette policies and adolescent use and, second, with access to e-cigarettes. We subsequently tested interactions between age and each policy and present average marginal effects as percentage point (pp) changes. Results: While MLSA laws for e-cigarettes were associated with slight increases in e-cigarette use (2.72 pp; 1.29, 4.15), associations were no longer significant after at least 1-year post-implementation. MLSA laws were also associated with decreases in e-cigarette purchases in stores (-9.50 pp; -18.21, -0.79) and increases in acquiring them from someone else (13.26 pp; 4.10, 22.42), particularly among 18-year-olds. E-cigarette taxes were associated with decreases in use (-9.18 pp; -11.63, -6.73), but there were limited associations with e-cigarette access. While smoke-free legislation prohibiting e-cigarettes was associated with slight increases in use (1.87 pp; 0.23, 3.50), after at least 1-year post-implementation, they were associated with decreases in use. Smoke-free legislation was also associated with decreases in purchases in stores by 14-year-olds, but increases in online purchases by 18-year-olds. Conclusion: Understanding the immediate and longer-term consequences of e-cigarette policies is essential to influence adolescent e-cigarette use. Adolescents will continue acquiring e-cigarettes across varying sources if measures are not taken to address access alongside policies aimed at reducing use.