Contribution of Smoking to Tuberculosis Incidence and Mortality in High Tuberculosis Burden Countries

Abstract

Globally, 10 million incident tuberculosis (TB) cases are reported annually; 95% of TB cases and 80% of tobacco users reside in low- and middle-income countries. Smoking approximately doubles the risk of TB disease and TB mortality. We estimated the proportion of annual incident TB cases and TB mortality attributable to tobacco smoking in 32 high TB burden countries. We obtained country-specific estimates of TB incidence, TB mortality, and smoking prevalence from the World Health Organization Global TB Report (2017), tobacco surveillance reports (2015), and the Tobacco Atlas. Risk ratios for the effect of smoking on TB incidence and TB mortality were obtained from published meta-analyses. An estimated 17.6% (95% confidence interval (CI): 8.4, 21.4) of TB cases and 15.2% (95% CI: 1.8, 31.9) of TB mortality were attributable to smoking. Among high TB burden countries, Russia had the highest proportion of smoking-attributable TB disease (31.6%, 95% CI: 15.9, 37.6) and deaths (28.1%, 95% CI: 3.8, 51.4). Men (30.3%, 95% CI: 14.7, 36.6) had a greater proportion of TB cases attributable to smoking than women (4.3, 95% CI: 1.7, 5.7). Our findings highlight the need for tobacco control in high TB burden countries to combat TB incidence and TB mortality.