Trends and cross-country inequality in the incidence of gastrointestinal cancers among the working-age population from 1990-2021: a global burden of disease 2021 analysis

Background: Gastrointestinal (GI) cancers pose an increasing global health burden, with their impact on the working-age population (WAP) aged 15-64 years remaining largely unexplored despite the crucial role of this group in societal and economic well-being. To assess trends and cross-country inequality in the global burden of six gastrointestinal cancers from 1990-2021 among individuals in the WAP. Methods: The 2021 Global Burden of Disease (GBD) study dataset was used to obtain estimates of gastrointestinal cancer incidence and 95% uncertainty intervals, including the number of cases, crude incidence rate, and age-standardized incidence rate (ASIR). WAP gastrointestinal cancer epidemiology was assessed at the national, regional, and global levels, evaluating trends from 1990-2021 from overall, local, and sociodemographic index (SDI) perspectives and utilizing standard health equity methods to quantify cross-country inequality. Findings: Colorectal cancer exhibited the greatest burden of gastrointestinal cancer among the WAP in 2021. From 1990-2021, the number of gastrointestinal cancer cases rose by 51.9%, although the ASIR declined by 23.4%. These rates exhibit geographic variation, with the most cases and the highest ASIR in China and Mongolia, respectively. Incidence was disproportionately concentrated in higher SDI countries, and worsening inequality was evident over time. Interpretation: While the ASIR of gastrointestinal cancer is trending downwards among the WAP, high incidence rates, regional variability, and an unequal burden of disease emphasize the need for flexible, targeted medical interventions to support policymaking and medical resource allocation.