Abstract A041: Assessing the impact of neighborhood structural racism on survival for African American men with prostate cancer; a population-based cancer registry study across eight US states

Abstract Background: African American (AA) men are more than twice as likely to die of prostate cancer (PC) compared to non-Hispanic White men in the US. Among AA men, we examined survival after PC diagnosis by neighborhood-level structural racism and whether its effects are mediated by neighborhood socioeconomic status (nSES). Methods: We pooled data for 133,241 AA men diagnosed with PC from 2000-2013 from ten population-based cancer registries across eight states (CA, Detroit, FL, GA, LA, NJ, NY, TX) of the RESPOND Study (Research on Prostate Cancer among African American Men). Residential addresses at PC diagnosis were geocoded and appended to census block-group measures of structural racism (contemporary redlining, racial/ethnic segregation typology, and racial bias in mortgage lending) and nSES, an index comprising measures of income, education, occupation, employment, and housing. We used Cox models and the %mediation SAS macro for causal mediation to assess overall and PC- specific survival according to structural racism and to quantify the extent to which survival differences were mediated by nSES. Models were adjusted for diagnosis year and age, state of residence, and marital status. Results: There were 46,830 deaths overall with 12,272 PC-specific deaths among the study population. Greater mortality risk was observed among AA men residing in neighborhoods in the highest compared to lowest quartile of redlining (total effect) for both overall survival (Hazards ratio [HR]=1.26; 95% CI=1.22, 1.31) and PC-specific survival (HR=1.30; 95% CI=1.21-1.39). Neighborhood SES mediated 59% and 47% of the effect of redlining, resulting in natural direct effects of HR=1.11 (95% CI=1.05, 1.17) and HR=1.16 (95% CI=1.04, 1.29) for overall and PC-specific survival, respectively. Compared to predominantly White neighborhoods, AA men residing in neighborhoods with all other racial/ethnic typologies had greater overall and PC-specific mortality risk, with largest risk for neighborhoods with predominantly AA or mixed with Hispanic and AA residents. Neighborhood SES completely mediated the effect of racial/ethnic typology on survival for all typologies except that of mixed Hispanic and Black residents (37% and 25% mediation by nSES for overall and PC-specific survival, respectively). There was no association between racial bias in mortgage lending and survival. Results from models additionally adjusted for prognosis (Prostate Cancer Cohort Consortium [PC3] classification of aggressive disease) and treatment (receipt of surgery, radiation, chemotherapy, or hormone therapy) were similar. Conclusions: Neighborhood SES explains substantial portions of the impact of redlining and racial/ethnic typology on overall and PC-specific survival among AA men across eight states in the US. Remaining survival differences for the most redlined neighborhoods and neighborhoods with a mix of Hispanic and Black residents independent of nSES suggest alternative pathways for the impact of neighborhood structural racism on mortality risk for AA men with PC. Citation Format: Mindy C. DeRouen, Meera Sangaramoorthy, Katherine Lin, Annie Vu, Dan Meltzer, Pushkar Inamdar, Yuhong Zhou, Kevin Ward, Xiao-Cheng Wu, Antoinette Stroup, Jennifer Beebe-Dimmer, Anshu Shrestha, Aaron P. Thrift, Margaret Gates-Kuliszewski, Peter Kanetsky, Tamara Lotan, Anthony Colombo, David Conti, Christopher Haiman, Ann Hamilton, Kirsten Beyer, Joseph Gibbons, Iona Cheng, Salma Shariff-Marco, Scarlett Gomez. Assessing the impact of neighborhood structural racism on survival for African American men with prostate cancer; a population-based cancer registry study across eight US states [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A041.