A model-based comparison of life expectancy by smoking status
摘要
Tobacco smoking is associated with significantly increased risks of lung cancer, cardiovascular disease, COPD, and other serious illnesses. Globally, it causes more than 7 million deaths annually, about 75% of which occur in men. This study compared the life expectancy of smokers and non-smokers in India (2019) using life table analysis.
MethodsTwo modelling scenarios were considered: one assuming deaths are uniformly distributed across each age interval and another assuming an increasing (exponential) distribution of deaths within intervals. Smoking prevalence data came from the Global Adult Tobacco Survey (GATS-2), and mortality data from the Global Burden of Disease (GBD) study. Life expectancy was calculated from age 30 onward, and a sensitivity analysis was performed using GBD’s upper- and lower-bound mortality estimates.
ResultsSmokers had a shorter life expectancy than non-smokers, and this gap widened with age. On average, smokers lived about 2.7 years less than non-smokers for males and 4.2 years less for females. Using the higher mortality (upper-bound) scenario for smokers increased the gap to ~ 6.4 years (males) and ~ 8.8 years (females). Notably, the choice of death distribution model (uniform vs. increasing) had a negligible effect on the results.
ConclusionThe substantial life expectancy gap between smokers and non-smokers—especially under worst-case mortality scenarios—underscores the need to strengthen tobacco control and cessation initiatives in India.