Global, regional, and national deaths, disability-adjusted life years, years lived with disability, and years of life lost for the global disease burden attributable to second-hand smoke, 1990-2019: A systematic analysis for the Global Burden of Disease Study

Background: Smoke-free policies have led to a decline in smoking prevalence. Nevertheless, as the global population grows, more non-smokers are exposed to second-hand smoke (SHS) hazards. Mitigating SHS hazards requires a systematic analysis of the global disease burden attributable to SHS. Methods: Data on SHSwas extracted from the Global Burden of Disease Study 2019. First, wemeasured the disease burden of SHS by the number of cases and age-standardized rates of deaths, disability-adjusted life years (DALYs), years livedwith disability (YLDs), and years of life lost (YLLs) from 1990 to 2019. Second, trends in the disease burden of SHS in different periods were estimated based on the annual percentage change (APC) by joinpoint regression analysis. Finally, using histogram plots, world maps, Pearson correlation analysis, and population attributable fraction (PAF), we conducted a stratified analysis of SHS exposure by sex, age, geographic location, sociodemographic index (SDI) level, and disease. Results: The number of deaths caused by SHS remained stable between 1990 and 2019, and the number of YLDs more than doubled in three decades. In contrast, the number of DALYs and YLLs caused by SHS decreased. The declining trend in deaths (APC=-1.42%[95% UI-1.79 %,-1.05 %]), DALYs (APC=-1.91%[95% UI-2.15 %,-1.67 %]), and YLLs (APC=-1.28 % [95 % UI-1.93 %,-0.64 %]) had slowed down in recent years, while SHS-related YLDs were still increasing (APC= 1.84%[95% UI 0.74%, 2.96%]). From 2010 to 2019, we found that SHS exposure increased the risk of tracheal, bronchus, and lung cancer (PAF increased by 11.75%), breast cancer (PAF increased by 5.36%), diabetes mellitus (PAF increased by 8.24%), and ischemic heart disease (PAF increased by 4.46%). In addition, the disease burden caused by SHS was highest in middle SDI and low-middle SDI countries. Conclusion: The global disease burden attributable to SHS is still severe, and policymakers need to implement more effective measures to reduce the harm of SHS.