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 Status Quo scenario. For tax scenarios, the authors estimated the impact of a $1 increase in cigarette tax (Cigarette Tax), e-cigarette tax (E-cig Tax), or both (Combined Tax). They performed sensitivity analysis around transition parameters and tax effects to evaluate the influence of uncertainty in these estimates.

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.