Racial Equity among African-American and Non-Hispanic White Men Diagnosed with Prostate Cancer in the Veterans Affairs Healthcare System

Abstract

African-American (AA) men in the general U.S. population are more than twice as likely to die from prostate cancer than Non-Hispanic White (NHW) men. Racial disparities decrease after the age of 65 when patients become eligible for equal-access Medicare insurance. We hypothesized that receipt of healthcare through the Veterans Affairs Health System, an equal-access medical system, would attenuate disparities between AA and NHW men of all ages. We identified patients diagnosed with prostate cancer between 2000-2015 using the Department of Veterans Affairs (VA) Informatics and Computing Infrastructure (VINCI). We used a combination of database/registry coded values and chart review to assemble tumor, treatment, comorbidity, and sociodemographic data and then ascertained date and cause of death using the Social Security death index. Prostate cancer-specific mortality (PCSM) was evaluated using Fine-Gray regression and cumulative incidence function plots. A mediation analysis was performed using sequential variable analysis. The cohort included 60,035 men (18,201 (30.3%) AA, 41,834 (69.7%) NHW) followed for a median of 5.9 years. AA men were more likely to be from regions with lower median income (AA 45,069 vs NHW 51,973, p<0.001) and lower high school graduation rates (AA 0.83% vs NHW 0.87%, p <0.001). They were also younger (AA mean age 63.6 vs NHW 67.2, p<0.001), and had higher median PSA at presentation (AA 6.7 vs NHW 6.2, p<0.001). However, AA men were equally or less likely to present with Gleason 8-10 disease (AA 18.8% vs NHW 19.7%, p<0.001), clinical T-stage 3 or higher (AA 2.2% vs NHW 2.9%, p<0.001), clinical node positive disease (AA 1.4% vs NHW 1.5%, p=0.33) or distant metastatic disease (AA 2.7 vs NHW 3.1, p = 0.01). The unadjusted 10-year incidence of PCSM for AA and NWH men was 4.4% versus 5.1%, respectively. On multivariable analysis, AA men had improved PCSM (subdistribution hazard ratio: 0.85; 95% confidence interval: 0.78-0.93; p < 0.001). Sequential variable analysis did not identify any variables mediating this effect. AA men demonstrated an improved 10-year overall survival (AA 18% vs NHW 23%), with adjusted hazard ratio of 0.84 (0.81-0.88; p<0.001). African-American men diagnosed with prostate cancer in the VA system do not present with more advanced disease or suffer from worse outcomes compared to NHW men despite generally residing in regions with lower socioeconomic status. These findings suggest that access to care is an important determinant of racial equity in prostate cancer diagnosis, receipt of appropriate care, and survival outcomes.