S941 Burden Beyond Borders: A Global Benchmarking Analysis of High BMI-Attributable Gallbladder Cancer Mortality and Disability in 204 Countries and Territories (1990-2021)

Introduction: Obesity, driven by sedentary lifestyles and dietary shifts, is a growing global concern and a key contributor to chronic diseases, including gastrointestinal cancers. Among them, gallbladder and biliary tract cancer (GBBTC) exhibits a strong link to high body mass index (BMI), yet its burden remains poorly characterized. Methods: The burden of GBBTC attributable to high BMI was estimated using the Global Burden of Disease 2021 comparative risk assessment framework, which quantifies exposure-related outcomes through population attributable fractions (PAFs). PAFs were calculated based on BMI exposure distributions, established relative risks, and a theoretical minimum risk exposure level. Age-standardized mortality, years lived with disability (YLDs), and disability-adjusted life years (DALYs) were assessed across 204 countries and territories from 1990 to 2021. Trends over time were measured using annual percent change (APC). Results: From 1990 to 2021, the APC in the total number of deaths due to GBBTC attributable to high BMI increased by 1.08% (95% uncertainty interval [UI] 0.87%-1.25%), while DALYs rose by 0.98% (95% UI 0.76%-1.17%) and YLDs by 1.56% (95% UI 1.31%-1.78%). Stratified by socio-demographic index (SDI), the greatest increase in APC for deaths was observed in low-middle SDI countries (3.08%), followed by low SDI (2.66%), middle SDI (2.33%), high-middle SDI (0.84%), and high SDI regions (0.47%). Age-wise analysis revealed that individuals aged 55 years and older experienced the highest APC in deaths (1.10%) and YLDs (1.60%), compared to those aged 20-54 years (0.88% for deaths and 1.38% for YLDs). Years of life lost (YLLs) followed a similar pattern, with APCs of 1.01% for the 55+ year age group and 0.87% for the 20-54 year age group. By gender, men exhibited a consistently higher burden than women, with APCs for deaths at 1.61% vs 0.83%, YLDs at 2.31% vs 1.18%, and YLLs at 1.40% vs 0.76%, respectively. Conclusion: GBBTC linked to high BMI has increased significantly since 1990, especially in low and middle SDI regions, older adults, and men. This trend reflects a shifting global epidemiology where obesity is no longer confined to affluent societies but is rapidly amplifying cancer risk in vulnerable populations. The rising burden across both fatal and non-fatal outcomes highlights an urgent need for targeted obesity prevention, early detection, and resource-tailored cancer control strategies.