Abstract
BACKGROUND: Colorectal cancer (CRC) remains the second leading cause of cancer-related death in the USA. This study systematically assessed the spatiotemporal evolution of CRC mortality from 1999 to 2023 and explored sociodemographic and geographic disparities. METHODS: Death-certificate data for adults aged ≥ 25 years were extracted from the CDC WONDER database. CRC deaths were identified using ICD-10 codes C18-C20. Age-adjusted mortality rates (AAMR) were calculated with the 2000 US standard population. Stratified analyses were performed by age, sex, race/ethnicity, census region, state, and National Center for Health Statistics urban-rural classification. Joinpoint regression estimated annual percent change (APC) and average annual percent change (AAPC). RESULTS: AAMR rose annually by 0.45% in the 25-34-year group and 1.03% in the 35-44-year group but declined significantly among individuals ≥ 55 years (AAPC -1.43% to -3.20%). Adults ≥ 75 years accounted for more than half of CRC deaths. The South registered the highest AAMR (21.13 per 100,000), whereas the Northeast had the lowest (17.31 per 100,000). Non-Hispanic Black individuals experienced the highest AAMR (24.90 per 100,000). Nonmetropolitan counties showed higher AAMR (23.16 per 100,000) than metropolitan counties (18.69 per 100,000). CONCLUSION: Despite an overall decline in US CRC mortality, rising risk among young adults and pronounced disparities across regions, racial/ethnic groups, and urban-rural settings persist. Targeted screening and intervention strategies for younger populations, high-burden areas, and vulnerable groups are essential to accelerate equitable reductions in CRC mortality.