Socioeconomic status, race, and long-term outcomes after radical prostatectomy in an equal access health system: Results from the SEARCH database

IntroductionWe previously found racial differences in biochemical recurrence (BCR) after radical prostatectomy (RP) persisted after adjusting for socioeconomic status (SES) while SES did not predict BCR. The impact on long-term prostate cancer (PC) outcomes is unclear. We hypothesized higher SES would associate with better long-term outcomes regardless of race.MethodsAmong 4,787 black and white men undergoing RP from 1988 to 2015 in the SEARCH Database, poverty (primary SES measure) was estimated by linking home ZIP-code to census data. Cox models were used to test the association between SES adjusting for demographic, clinicopathological features, and race with BCR, castration-resistant PC (CRPC), metastases, PC-specific mortality (PCSM), and all-cause mortality. Interactions between race and SES were tested.ResultsMedian follow-up was 98 months (Interquartile range: 54-150 months). There were no interactions between race and SES for BCR. Black men had 10%- to 11% increased BCR risk (P < 0.06) while SES was unrelated to BCR. There were interactions between SES and race for CRPC (P = 0.002), metastasis (P = 0.014), and PCSM (P = 0.004). Lower SES was associated with decreased CRPC (P = 0.012), metastases (P = 0.004), and PCSM (P = 0.049) in black, but not white men (all P ≥ 0.22). Higher SES was associated with decreased all-cause mortality in both races.ConclusionsIn an equal-access setting, lower SES associated with decreased CRPC, metastases, and PCSM in black but not white men. If confirmed, these findings suggest a complex relationship between race, SES, and PC with further research needed to understand why low SES in black men decreased the risk for poor PC outcomes after RP.