Global, regional and national burden of colorectal cancer and its risk factors, 1990-2021: a systematic analysis for the GBD 2021

Importance: Colorectal cancer (CRC) represents a significant portion of the global cancer burden, underscoring the need for a detailed epidemiological assessment. This analysis is essential for informing targeted public health interventions and guiding strategic resource allocation. Objective The present study aims to conduct a comprehensive analysis of the global, regional, and national burden of CRC and its associated risk factors from 1990 to 2021, utilizing data from the Global Burden of Disease (GBD) 2021 study. Methods A comprehensive analysis was conducted to assess the distribution of CRC across 204 countries and territories, focusing on the burden in relation to age, gender, and geographic location. The study also evaluated the impact of key risk factors on disability-adjusted life years (DALYs) across 21 GBD regions. A Bayesian age-period-cohort (BAPC) model was employed to project the future trajectory of CRC over the next three decades. Findings: The 2021 global incidence of CRC is projected to be approximately 2,194,143 cases (95% uncertainty interval [UI], 2,001,272 to 2,359,390), with a prevalence of 11,679,120 (95% UI, 10,774,527 to 12,538,400) and 24,401,100 DALYs (95% UI, 22,689,369 to 26,161,518) worldwide. Significant regional variations in the burden of CRC were observed, with Central Europe experiencing the highest impact. The burden of CRC increases with age, peaking among the elderly population aged 84 to 94 years. From 1990 to 2021, the age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and age-standardized disability-adjusted life years rate (ASDR) for CRC showed an upward trend, with a more pronounced burden observed in males compared to females. Future projections suggest a potential decrease in burden of CRC, with a more substantial reduction expected among females. Conclusion The study reveals regional disparities in the burden of CRC, with Central Europe being the most significantly affected region. Dietary risk factors were identified as primary contributing factor. These findings enhance our understanding of the global distribution and variation in CRC prevalence, providing valuable insights for cancer control planning.