Abstract 3610: Healthcare segregation experienced by colorectal cancer patients residing in high-poverty areas and its impact on health outcomes

Background: Existing evidence indicates that colorectal cancer (CRC) patients from high-poverty areas (HPA), defined as areas with 20% or more residents living below federal poverty level, are more likely to receive surgery at low-volume, non-accredited hospitals than those from low-poverty areas (LPA). The systematic difference in surgical care location between patients from HPAs and LPAs, healthcare segregation, could represent a structural equity through which disparities in health outcomes arise. We sought to determine the existence of healthcare segregation and assess its impact on patient health outcomes. Methods: We identified patients undergoing surgery for non-metastatic CRC diagnosed in 2009-2019 from SEER-Medicare. Patients living in a county which had been an HPA for at least 30 years were classified as living in a persistent-poverty area (PPA). Patients living in a county which was an HPA during the year of cancer diagnosis but not a PPA were classified as living in a current-poverty area (CPA). Otherwise, they were classified as living in an LPA. Experiencing healthcare segregation was defined as being treated at a poverty-area-serving (PAS) hospital where ≥50% of the patients were from HPAs. We examined the association between area-level poverty, treatment at PAS hospitals, and health outcomes (postoperative adverse events, 30-day readmission, long-term all-cause mortality (ACM), and cancer-specific mortality (CSM)) using logistic and Cox regression. We performed a subgroup analysis for metropolitan, urban, and rural areas. Results: We included 81,767 patients (7.5% from PPAs, 8.4% from CPAs) with a median age of 78 (IQR: 73-84) years. 53.9% of patients were females, 14% were non-White, and 1.5% lived in rural areas. 81% of the hospitals (180/991) were PAS hospitals, which treated 64% of patients from PPAs and CPAs vs. 3% from LPAs. Compared with patients from LPAs treated at non-PAS hospitals, those treated at PAS hospitals who were from PPAs (ACM HR=1.17(1.08-1.26), CSM HR=1.23(1.11-1.37)) and CPAs (ACM HR=1.15(1.08-1.22), CSM HR=1.23(1.13-1.35)) had worse short and long-term outcomes. Patients from CPAs treated at non-PAS hospitals also had worse outcomes, to a lesser degree (ACM HR=1.12(1.05-1.19), CSM HR=1.16(1.06-1.28)). Among rural residents, being treated at PAS-serving hospitals but not area-level poverty was independently associated with worse outcomes. Conclusions: Patients living in HPAs experience healthcare segregation in CRC treatment, contributing to their worse health outcomes. Healthcare segregation reflects systemic inequities and structural barriers limiting access to resources that patients from HPAs may deploy to mitigate consequences of cancer. Understanding healthcare segregation and factors shaping it can help identify areas for intervention to reduce associated health disparities. Citation Format: Xinyan Zheng, Laura C. Pinheiro, Parisa Tehranifar, Erica Phillips, Rulla M. Tamimi, Steven Y. Chao, Maria Pisu, Chuxuan Gao, Andrew G. Rundle, Jialin Mao. Healthcare segregation experienced by colorectal cancer patients residing in high-poverty areas and its impact on health outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3610.