S680 The Cost of Waiting: Rising Colorectal Cancer Mortality in Adults Under 50 Before Lowering of Screening Age

Introduction: Colorectal Cancer (CRC) has long been viewed as a disease of older adults. However, over the past 2 decades, a troubling shift has occurred. An increasing number of CRC-related deaths in adults under 50 has been emerging, many of whom fall outside the traditional screening age. Recent analysis from the Global Burden of Diseases shows faster mortality rises in younger vs older adults (APC: 1.6 vs 0.6). In the U.S., CRC screening age was only lowered from 50 to 45 in 2021, despite alarming data. Our study analyzes mortality data from 1999-2023 in adults aged under 55, indicating the potential cost of a delayed screening policy. Methods: We analyzed age-adjusted mortality rates (AAMR) of early-onset CR related (EO-CRC) deaths in adults ≤55 in the US using the CDC WONDER database. AAMR per 100,000 were extracted and stratified by sex and census region. Joinpoint regression analysis was used to calculate annual percent changes (APC) and identify significant inflection points in trends using the Monte Carlo Permutation test. The final model selection was based on statistical significance at P < 0.05. Results: A total of 166,359 deaths were observed among adults ≤55 between 1999 and 2023. Overall, AAMR rose from 3.76 in 1999 to 4.39 in 2023. Joinpoint analysis identified 4 inflection points: a significant increase between 2005-2008 (APC: 2.92), a minor dip, and then a renewed rise from 2019-2023 (APC: 1.93). Men had higher AAMRs than women (2023: 5.05 vs 3.7). Regionally, the South reported the highest number of deaths (69,675) with AAMR (2023: 4.86), followed by the Midwest (4.25), West (4.03) and Northeast (3.87). Northeast exhibited the steepest rise during 2005-2008 (APC: +4.0), highlighting regional disparities in EO-CRC mortality. Conclusion: This nationwide analysis revealed a clear inflection in EO-CRC mortality. A significant spike during 2005-2008 and again from 2019-2023 suggests missed prevention opportunities before the changes in guidelines. The regional and gender analysis shows disparities in early-onset outcomes. Supporting these trends, Abboud Y et al. [1] early detection of CRC in individuals under 50 significantly improves survival odds, emphasizing the importance of timely screening. As the burden of age-associated diseases begins to shift earlier in life, this study raises a broader question: Should we re-evaluate screening thresholds for other chronic conditions traditionally reserved for older populations? Reference Abboud Y, Shah A, Fraser M, et al. Rising Incidence and Mortality of Early-Onset Colorectal Cancer in Young Cohorts Associated with Delayed Diagnosis. Cancers (Basel). 2025;17(9):1500.