Abstract
BACKGROUND: Using Global Burden of Disease (GBD) 2021 data, we quantified the global, regional, and national burdens and trends of lower respiratory infections (LRIs) attributable to smoking and secondhand smoke exposure from 1990 to 2021. Our findings aim to inform evidence-based strategies for more effective prevention and control. METHODS: Based on the GBD 2021, we analyzed age-standardized mortality rates (ASMRs) and age-standardized disability-adjusted life year rates (ASDRs) across the 204 countries and territories. We then evaluated trends using estimated annual percentage changes (EAPCs). The temporal evolution of the disease burden, its relationship with the sociodemographic index (SDI), and the independent effects of population growth, ageing, and epidemiological changes were examined. Additionally, cross-national inequality analyses and projections of the disease burden through 2050 were conducted. RESULTS: In 2021, the global ASMR for LRIs attributable to smoking was 2.32 per 100,000 people, with an ASDR of 52.04 per 100,000 person-years. For secondhand smoke, the ASMR was 2.01 per 100,000 people, with an ASDR of 88.26 per 100,000 person-years. In the 5 SDI regions, the burden of LRIs attributable to smoking was most severe in the low-middle SDI, whereas the burden attributable to secondhand smoke was most significant in the low SDI. Furthermore, the burden of LRIs attributable to both smoking and secondhand smoke was especially pronounced in countries such as Lesotho and the Solomon Islands. The smoking-attributable LRIs burden increased with age, whereas the burden of secondhand smoke exposure was notably high in children under 5 years of age. Forecast analyses predict a significant decrease in the ASMR and ASDR for LRIs attributable to smoking and secondhand smoke exposure from 2022 to 2050. CONCLUSION: Despite a global decline in the burden of LRIs attributable to smoking and secondhand smoke, significant inequalities persist. Future tobacco control must be targeted to high-risk regions and populations, particularly children under 5 years old exposed to secondhand smoke and older adults affected by both smoking and secondhand smoke, in order to further reduce the burden of LRIs.