A predictive model that replaces cigarette smoking with vaping projects nearly 21 million fewer life-years lost.
A large-scale push to replace cigarette smoking with vaping could be life saving for millions of Americans, says a study authored by a multidisciplinary, multicenter team of investigators affiliated with Georgetown University, Roswell Park Cancer Institute, University of Michigan, Yale, and a number of other organizations dedicated to public health and cancer research.
At least 1.6 million premature deaths could be averted and 20.8 million fewer life-years lost, according to the predictive models used by the group.
Although the prevalence of tobacco use in the United States has significantly decreased over the past 5 decades, 2 out of 3 long-term smokers will suffer premature death associated with the habit. Tobacco control experts and health policy lawmakers continue to brainstorm what more can be done to further reduce tobacco use and the harms it causes.
Nicotine delivery via electronic (e) cigarettes, so-called vaping, is being seen by some public health experts as a means to this end while others fear that it may compound the problem. Authors of the current study, however, are of the opinion that vaping is safer than cigarette smoking and that encouraging the former as replacement for the latter may be a step toward the ultimate public health goal: elimination of all tobacco consumption.
Status quo vs e-cig substitution
The researchers compared a Status Quo Scenario of cigarette smoking rates and health outcomes with E-cigarette Substitution models. The Status Quo Scenario, based on past cigarette smoking uptake and cessation rates through the year 2021, focused on health and mortality outcomes in the general population among never, current, and former cigarette smokers. Retrospective and prospective data were calculated. Two prospective E-cigarette Substitution models that provide a best case scenario (Optimistic Scenario) and worst case scenario (Pessimistic Scenario) were developed, with the former assuming a 5% residual prevalence of cigarette use and the latter a 10% residual use by 2026. Variables factored into the analysis included age, sex, prospective smoking/vaping cessation, and other risk-assessment factors.
According to the Status Quo Scenario, current smoking prevalence in the United States is 19% among men and 14% among women age ≥15 years, translating to a prospective 26.1 million premature deaths and 248.6 million life-years lost.
Compare this with the Optimistic and Pessimistic E-Cigarette Substitution Scenarios. Under the Optimistic Scenario, 19.5 million premature deaths and 161.9 million life-years lost are projected, amounting to 25% fewer premature deaths and 35% fewer life-years lost. Under the Pessimistic Scenario, 24.4 million premature deaths and 227.8 million life-years lost are projected, representing 6% fewer premature deaths and 8% fewer life-years lost compared with the Status Quo Scenario. Results are summarized in the Table.
When the researchers examined results in relation to younger (age 15 years in 2016) and older (age 35 in 2016) population groups, they found that younger persons can expect to have a survival advantage by replacing cigarette smoking with vaping-a 0.5 year gain in life expectancy. The study authors also pointed out that the number of premature deaths and life-years lost in all scenarios were found to be primarily due to the impact of smoking among persons who were age 35 years and older in 2016. The study findings suggest that, even under a worst case scenario regarding future trends in tobacco use, substantial public health gains could be achieved by encouraging cigarette smokers to switch to vaping.
Source: Levy DT, Borland R, Lindblom EN, et al. Potential deaths averted in USA by replacing cigarettes with e-cigarettes. Tob Control. 2017 Oct 2. [Epub ahead of print]