Global burden, trends, and risk factors of early-onset and late-onset colorectal cancer from 1990 to 2021, with projections to 2040: a population-based study

Early-onset colorectal cancer (EOCRC) and late-onset colorectal cancer (LOCRC) are significant public health concerns. There has been limited research comparing EOCRC and LOCRC, particularly regarding their global burden. This study used data from the Global Burden of Disease (GBD) 2021 study, covering 204 countries and territories from 1990 to 2021. We analyzed incidence, prevalence, mortality, and disability-adjusted life years (DALY) for EOCRC and LOCRC. Age-standardized rates per 100,000 population were calculated, and trends were assessed using Joinpoint regression analysis. Decomposition analysis identified factors influencing DALY changes, with future burden projections through 2040. From 1990 to 2021, EOCRC cases nearly doubled, rising from 107,309 to 211,890, with the age-standardized incidence rate increasing from 4.58 to 5.15 per 100,000. LOCRC cases more than doubled, from 809,273 to 1,982,252, with the incidence rate rising from 79.67 to 84.38 per 100,000. Despite rising incidence, both EOCRC and LOCRC saw declines in mortality and DALY rates, reflecting improved treatment outcomes. In 2021, East Asia bore the highest burden of both EOCRC and LOCRC. The leading risk factors for both EOCRC and LOCRC were low intake of whole grains, low milk intake, and high red meat intake. Projections suggest incidence and prevalence of both cancers will continue rising through 2040, while mortality and DALY rates will decline, with LOCRC remaining predominant. EOCRC incidence is rising rapidly, but LOCRC still accounts for the majority of cases globally. Targeted prevention, better screening, and efficient resource allocation are crucial to addressing this public health challenge.