Smoking prevalence and attributable disease burden in 195 countries and territories, 1990–2015: a systematic analysis from the Global Burden of Disease Study 2015

Background The scale-up of tobacco control, especially after the adoption of the Framework Convention for TobaccoControl, is a major public health success story. Nonetheless, smoking remains a leading risk for early death anddisability worldwide, and therefore continues to require sustained political commitment. The Global Burden ofDiseases, Injuries, and Risk Factors Study (GBD) offers a robust platform through which global, regional, andnational progress toward achieving smoking-related targets can be assessed.Methods We synthesised 2818 data sources with spatiotemporal Gaussian process regression and produced estimatesof daily smoking prevalence by sex, age group, and year for 195 countries and territories from 1990 to 2015. We analysed38 risk-outcome pairs to generate estimates of smoking-attributable mortality and disease burden, as measured bydisability-adjusted life-years (DALYs). We then performed a cohort analysis of smoking prevalence by birth-year cohortto better understand temporal age patterns in smoking. We also did a decomposition analysis, in which we parsed outchanges in all-cause smoking-attributable DALYs due to changes in population growth, population ageing, smokingprevalence, and risk-deleted DALY rates. Finally, we explored results by level of development using theSocio-demographic Index (SDI).Findings Worldwide, the age-standardised prevalence of daily smoking was 25·0% (95% uncertainty interval [UI]24·2–25·7) for men and 5·4% (5·1–5·7) for women, representing 28·4% (25·8–31·1) and 34·4% (29·4–38·6)reductions, respectively, since 1990. A greater percentage of countries and territories achieved significant annualisedrates of decline in smoking prevalence from 1990 to 2005 than in between 2005 and 2015; however, only four countrieshad significant annualised increases in smoking prevalence between 2005 and 2015 (Congo [Brazzaville] andAzerbaijan for men and Kuwait and Timor-Leste for women). In 2015, 11·5% of global deaths (6·4 million [95% UI5·7–7·0 million]) were attributable to smoking worldwide, of which 52·2% took place in four countries (China, India,the USA, and Russia). Smoking was ranked among the five leading risk factors by DALYs in 109 countries andterritories in 2015, rising from 88 geographies in 1990. In terms of birth cohorts, male smoking prevalence followedsimilar age patterns across levels of SDI, whereas much more heterogeneity was found in age patterns for femalesmokers by level of development. While smoking prevalence and risk-deleted DALY rates mostly decreased by sex andSDI quintile, population growth, population ageing, or a combination of both, drove rises in overall smokingattributableDALYs in low-SDI to middle-SDI geographies between 2005 and 2015.Interpretation The pace of progress in reducing smoking prevalence has been heterogeneous across geographies,development status, and sex, and as highlighted by more recent trends, maintaining past rates of decline should notbe taken for granted, especially in women and in low-SDI to middle-SDI countries. Beyond the effect of the tobaccoindustry and societal mores, a crucial challenge facing tobacco control initiatives is that demographic forces arepoised to heighten smoking’s global toll, unless progress in preventing initiation and promoting cessation can besubstantially accelerated. Greater success in tobacco control is possible but requires effective, comprehensive, andadequately implemented and enforced policies, which might in turn require global and national levels of politicalcommitment beyond what has been achieved during the past 25 years.