Abstract Historical redlining was a racially motivated federal policy that began in the 1930s, during which lending entities refused to provide government-issued loans to Black, immigrant, Jewish, and other “undesirable populations." Subsequently, the Home Owners Loan Corporation created color-coded maps that graded neighborhoods from low to high risk, limiting affordable loans to White neighborhoods. A more contemporary approach to measuring social disadvantage is the Social Vulnerability Index (SVI). Previous research has indicated negative health outcomes linked to redlining; however, little investigation has focused on this connection within Kentucky communities in relation to cancer outcomes. This study examines the impact of redlining on breast cancer outcomes, including late-stage breast cancer diagnoses and mortality rates. Data for breast cancer patients were obtained from the Kentucky Cancer Registry and matched with geocodes for historical redlining and SVI data. The final sample included 1,556 cases in Jefferson and Fayette County, Kentucky. Results indicated individuals living in historically high-redlined areas reported a 1.85 higher odds of late-stage cancer diagnosis and 1.89 higher odds of cancer related mortality. SVI was found to be a non-significant mediator between historical redlining and late-stage breast cancer diagnosis (percent mediated=-48.60, p=0.191) and breast cancer mortality (percent mediated=37.95, p=0.183). This result suggests historical redlining accounts for breast cancer outcomes more than contemporary measures of social determinants of health. Citation Format: Maxwell Groznik, Sydney P. Howard, Na’Tasha Evans, Breyanna Walker, Samantha Jones, Lovoria Williams, Brittany Rice, Shavonnie Carthens, Brandi White, Regina Lewis, Ariel Arthur, Justin X. Moore. Mediating effects of Social Vulnerability Index on historical redlining and breast cancer outcomes abstract. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr B165.
Groznik et al. (Thu,) studied this question.