Tobacco-driven digestive disease burden: A China-US comparative analysis, 1990-2035.

INTRODUCTION: Smoking is a well-established risk factor for digestive diseases, yet direct comparisons of smoking-attributable digestive disease burden between nations with divergent tobacco control trajectories remain scarce. This study compared temporal trends, driving factors, and future projections of this burden in China and the United States from 1990 to 2023. METHODS: Using Global Burden of Disease 2023 data, we analyzed smoking-attributable digestive disease deaths and disability-adjusted life years. Joinpoint regression assessed temporal trends. Decomposition analysis partitioned burden changes into population growth, aging, and epidemiological components. Bayesian age-period-cohort models projected burden to 2035. RESULTS: From 1990 to 2023, age-standardized mortality rates for smoking-attributable digestive diseases declined by 77.2% in China (average annual percentage change, AAPC= -4.32; 95% CI: -4.42 - -4.21; p<0.001) and 58.0% in the United States (AAPC= -2.57; 95% CI: -2.66 - -2.48; p<0.001). Despite these rate reductions, absolute smoking-attributable deaths among those aged 90-94 years increased by 663.6% in China and 131.5% in the United States. Epidemiological change was the dominant driver of burden reduction, contributing 374.4% and 349.8% of the overall smoking-attributable death reduction in China and the United States, respectively, outweighing combined demographic pressures. Joinpoint analysis identified a transient increase in US smoking-attributable death rates during 2018-2021 (APC=2.51; p<0.05). Projections indicated continued declines in smoking-attributable rates through 2035. CONCLUSIONS: Despite substantial epidemiological improvements, population aging increasingly offsets rate declines, particularly among the oldest adults. Sustained, age-targeted tobacco control strategies are essential to address the evolving demographic burden.