Disparities in cigarette smoking and the health of marginalized populations in the U.S.: a simulation analysis

People with low socioeconomic status (SES) or serious psychological distress (SPD) in the U.S. face ongoing and future disparities in tobacco smoking. We sought to estimate how smoking disparities contribute to disparities in life expectancy and aggregate life-years in these marginalized subpopulations.

We used the Simulation of Tobacco and Nicotine Outcomes and Policy (STOP) microsimulation model to project life expectancy as a function of subpopulation (low SES, higher SES, SPD, or non-SPD) and cigarette smoking status. Low SES was defined as having at least one of the following: income below poverty, less than high school education, or Medicaid insurance. Higher SES individuals belonged to none of these categories. SPD was defined as Kessler-6 score ≥ 13; non-SPD was a Kessler-6 score < 13. To project individual life expectancy losses from smoking, we simulated 40-year-olds stratified by gender, subpopulation (by SES or by SPD, with no change), and smoking status (current/never, with no change). To project time to reach 5% cigarette smoking prevalence (U.S.) - reflecting one tobacco "endgame" threshold - in each subpopulation, we simulated the entire subpopulations of people with low SES, higher SES, SPD, and non-SPD, incorporating corresponding distributions of gender, age, and smoking status and accounting for changes in smoking behaviors and secular smoking trends. We then estimated total life-years accumulated under status quo and alternate scenarios in which smoking dynamics in the marginalized subpopulations matched those of their less marginalized counterparts.

The model showed that, for individuals with low SES or SPD, smoking is associated with substantial loss of life expectancy (9.8-11.5y). Marginalized subpopulations would reach 5% smoking prevalence 20y (low SES) and 17y (SPD) sooner if smoking trends mirrored their less marginalized counterparts; these differences result in 5.3 million (low SES) and 966,000 (SPD) excess life-years lost over 40y.

Differences in cigarette smoking portend substantial ongoing and future disparities in life expectancy and time to reach 5% smoking prevalence. Reducing tobacco-related disparities in the U.S. will require an explicitly equity-focused vision, and the tobacco endgame will only be truly achieved when it includes all groups.