Attributable burden of high BMI-related gastrointestinal tract cancers among middle-aged and elderly populations globally, 1990–2021 and projected to 2050: analysis of GBD 2021

Background: The global burden of gastrointestinal tract cancers (GICs)-specifically liver cancer (LC), colorectal cancer (CRC), gallbladder and biliary tract cancers (GBTCs), and pancreatic cancer (PC)-attributable to high body mass index (BMI) is of increasing concern, especially among middle-aged and elderly populations. Methods: Using data from the Global Burden of Disease (GBD) Study 1990-2021, we assessed deaths, disability-adjusted life years (DALYs), age-standardized mortality rates (ASMR), and estimated annual percentage changes (EAPC) for LC, GBTCs, CRC, and PC attributable to high BMI in middle-aged and elderly populations. We analyzed regional, national, and Socio-demographic Index (SDI)-stratified patterns and their association with SDI and Human Development Index (HDI). Forecasts to 2050 were based on historical trends in these age groups. Results: From 1990 to 2021, LC deaths increased by 363% to 40,958, with ASMR rising from 1.0 to 2.2 per 100,000 (EAPC: 2.4%). GBTC deaths rose by 109% to 19,035, but ASMR slightly declined from 1.1 to 1.0 (EAPC: -0.5%). CRC deaths increased by 140% to 92,013, with stable ASMR (4.9 to 5.0; EAPC: -0.1%). Pancreatic cancer mortality also increased globally (EAPC: 4.4%), with high-SDI regions bearing the highest burden and middle-SDI regions experiencing the fastest growth (EAPC: 18.1%). East Asia bore the highest burden for all cancers, while South Asia showed the fastest mortality increases (EAPC: 5.4% for LC, 2.9% for CRC). At the national level, China and India contributed the largest share of deaths, while Indonesia and Vietnam showed the fastest growth in mortality. High-SDI regions had the largest absolute burden, but middle-SDI regions exhibited the fastest growth. All cancers showed male predominance, peaking at ages 60-79 years (LC: 60-64; GBTCs: 65-69; CRC: 75-79). ASMR followed an inverted U-shaped curve with SDI and HDI, peaking at SDI 0.7-0.9. By 2050, CRC and LC are projected to see rising DALYs and Years Lived with Disability (YLDs) in middle-aged and elderly populations, while GBTCs remain stable, with declining Years of Life Lost (YLLs) rates across all cancers. Conclusion: The escalating burden of high BMI-related GICs-particularly LC, CRC, GBTCs, and PC-in aging populations, especially in developing regions, highlights the urgent need for targeted interventions in prevention, early detection, and survivorship care.