S958 Trends and Burden of Gastrointestinal Cancers Attributable to Smoking in the United States, 1990-2021: Insights From the GBD 2021 Comparative Risk Assessment Framework

Introduction: Tobacco use remains one of the most significant preventable causes of gastrointestinal (GI) cancers in the United States. Despite public health efforts to curb smoking, its long-term effects on cancer burden across digestive organs remain underexplored in comprehensive temporal frameworks. Methods: Utilizing the Global Burden of Disease Study 2021 comparative risk assessment framework, we quantified the burden of GI cancers attributable to smoking from 1990-2021 in the United States. Population-attributable fractions (PAFs) were estimated by comparing observed tobacco exposure distributions to theoretical minimum risk exposure levels. These PAFs were applied to total deaths, disability-adjusted life years (DALYs), and years lived with disability (YLDs) from GI cancers—including esophageal (EC), stomach (SC), colorectal (CRC), pancreatic (PC), and liver cancers (LC)—to estimate smoking-attributable fractions. Results: From 1990-2021 in the United States, smoking-attributable deaths due to LC rose from 774 (249-1,323) to 2,606 (807-4,612); PC from 5,096 (4,525-5,757) to 7,902 (6,668-9,411); and EC from 6,708 (5,350-7,955) to 9,973 (7,531-12,487). In contrast, deaths declined for CRC from 3,361 (2,084-4,705) to 3,115 (1,852-4,473), and SC from 2,974 (2,384-3,577) to 2,064 (1,597-2,577). Overall, DALYs due to smoking-related GI cancers increased from 460,872 (358,295-563,295) in 1990 to 591,286 (431,941-759,946) in 2021, reflecting a shift toward increased chronic disability among survivors. Age-wise, in 2021, smoking-attributable GI cancer deaths peaked in the 70- to 74-year age group, with DALYs highest in the 65- to 69-year group. CRC contributed the greatest share of YLDs, peaking in the 70- to 74-year age group. Gender-wise, men consistently exhibited higher Annual Percent Changes than women, with the steepest increases in LC (4.05% vs 3.83%), followed by PC (1.45% vs 1.39%) and EC (1.47% vs 0.43%), while CRC (-0.24% vs -0.25%) and SC (-1.28% vs -0.91%) showed declining trends. Conclusion: From 1990-2021, smoking-attributable GI cancer burden in the U.S. rose markedly—driven by increases in LC, PC, and EC deaths and DALYs—while CRC and SC declined; the burden was highest among older adults, more pronounced in men, and showed sharpest state-level rises in LC mortality. These trends underscore a growing chronic disability burden and the need for targeted, sex- and region-specific tobacco control efforts.