Projected Impact of Higher E-cigarette or Combustible Cigarette Taxes on Use of Both Products in the U.S.

Introduction: Higher taxes on e-cigarettes could reduce their use but might encourage combustible tobacco cigarette use. Simulation models enable evaluation of dynamic transitions between cigarette and e-cigarette use or nonuse and population-level projections in response to a policy change, such as higher taxes. Methods: The authors used a microsimulation model to project the relative impact of higher taxes on cigarettes, e-cigarettes, or both on the prevalence of cigarette and e-cigarette use among U.S. youth (aged 12-17 years), young adults (aged 18-24 years), and adults (aged ≥25 years). They used multi-state models to derive the probabilities of transition across states of current/former/never cigarette smoking and e-cigarette use from Waves 2-5 (2015-2019) of the Population Assessment of Tobacco and Health Study. These transition probabilities were applied to a simulated cohort in the Simulation of Tobacco and Nicotine Outcomes and Policy model, reflective of Wave 5 of the Population Assessment of Tobacco and Health Study, to project cigarette and e-cigarette use over 5 years in a Results: Compared with Status Quo, the relative changes among youth/young adults/adults in the prevalence of use at 5 years would be as follows: Cigarette Tax, -4%/-19%/-3% (cigarette use) and 0%/+3%/+3% (e-cigarette use); E-cig Tax, 0%/-10%/-2% (cigarette use) and -27%/-63%/-25% (e-cigarette use); and Combined Tax, -5%/-28%/-3% (cigarette use) and -27%/-62%/-25% (e-cigarette use). Model results were the most variable in young adults, reflecting greater uncertainty around tax effects in this population. The results of cigarette smoking and e-cigarette use prevalence, regardless of tax impact, were sensitive to the probabilities of initiation among youth and young adults and the probabilities of cessation among adults. Conclusions: A higher tax on e-cigarettes alone would likely reduce e-cigarette use prevalence at 5 years and might not increase cigarette smoking prevalence. A combined tax on both products would likely produce larger reductions in cigarette and e-cigarette use, maximizing public health benefits.