Defining Racial Disparities Across the Prostate Cancer Disease Continuum in an Equal Access-to-Care Setting Within the Nation's Largest Healthcare Network

Abstract

Purpose/Objective(s)Prostate cancer (PCa) is a complex disease, with risk factors and outcomes influenced by a combination of socioeconomic and biological factors. African American men (AAM) in the U.S. have higher incidence and mortality rates of PCa than European American men (EAM). Nonetheless, emerging studies have shown comparable outcomes across racial groups when treated in equal access settings. The Veterans Affairs (VA) healthcare system provides a unique environment to thoroughly investigate PCa disparities between AAM and EAM across the disease continuum, within relatively equal access-to-care settings.Materials/MethodsThis retrospective analysis consists of 7.8 million veterans undergoing routine care within VA hospitals nation-wide from 2005 to 2019. We compared PCa incidence, clinical presentation, treatment, and PCa specific outcomes among AAM and EAM veterans. Methods of categorical analysis were used to investigate the differences between race groups. We then assessed the likelihood of adverse clinical characteristics by race using logistic regression. In survival analysis, time-to-metastasis was used as a primary end point. Finally, we estimated the risk of distant metastasis in conjunction with treatment and baseline clinical characteristics using a multivariable cox proportional hazard model.ResultsConsistent with population-level data, AAM had an almost 2-fold greater risk of developing PCa than EAM within the relatively equal access-to-care VA network, with age-adjusted incidence rates of 96.7 and 40.1 per 100,000, respectively. Despite similar screening patterns, AAM also had a higher age-adjusted rate of metastasis at diagnosis compared with EAM - 5.66 and 2.37 per 100,000, respectively. AAM were more likely to have higher baseline PSA (aOR = 1.86, 95% CI, 1.77-1.95, P < 0.0001) and had higher Gleason score (aOR = 1.13, 95% CI, 1.09-1.16, P < 0.0001). Additionally, AAM also experienced slightly longer delay in receiving their primary treatment (124 vs 109 days, P < 0.0001). Among patients who had no record of definitive treatment, AAM had increased risk of distant metastasis (aHR = 1.26, 95% CI, 1.15–1.39, P = 0.002). However, AAM who received definitive treatment, particularly radiotherapy, showed overall improvement in distant metastasis compared to EAM (aHR = 0.86, 95% CI, 0.81–0.93, P < 0.0001).ConclusionThis comprehensive analysis reveals a national-level PCa incidence disparity in a relatively equal access-to-care network. AAM display a higher burden of both localized and metastatic PCa, placing them at a higher risk of adverse outcomes across the PCa continuum. Consequently, timely diagnosis and equitable treatment delivery are likely critical factors for reducing disparities in disease outcomes. Prostate cancer (PCa) is a complex disease, with risk factors and outcomes influenced by a combination of socioeconomic and biological factors. African American men (AAM) in the U.S. have higher incidence and mortality rates of PCa than European American men (EAM). Nonetheless, emerging studies have shown comparable outcomes across racial groups when treated in equal access settings. The Veterans Affairs (VA) healthcare system provides a unique environment to thoroughly investigate PCa disparities between AAM and EAM across the disease continuum, within relatively equal access-to-care settings. This retrospective analysis consists of 7.8 million veterans undergoing routine care within VA hospitals nation-wide from 2005 to 2019. We compared PCa incidence, clinical presentation, treatment, and PCa specific outcomes among AAM and EAM veterans. Methods of categorical analysis were used to investigate the differences between race groups. We then assessed the likelihood of adverse clinical characteristics by race using logistic regression. In survival analysis, time-to-metastasis was used as a primary end point. Finally, we estimated the risk of distant metastasis in conjunction with treatment and baseline clinical characteristics using a multivariable cox proportional hazard model. Consistent with population-level data, AAM had an almost 2-fold greater risk of developing PCa than EAM within the relatively equal access-to-care VA network, with age-adjusted incidence rates of 96.7 and 40.1 per 100,000, respectively. Despite similar screening patterns, AAM also had a higher age-adjusted rate of metastasis at diagnosis compared with EAM - 5.66 and 2.37 per 100,000, respectively. AAM were more likely to have higher baseline PSA (aOR = 1.86, 95% CI, 1.77-1.95, P < 0.0001) and had higher Gleason score (aOR = 1.13, 95% CI, 1.09-1.16, P < 0.0001). Additionally, AAM also experienced slightly longer delay in receiving their primary treatment (124 vs 109 days, P < 0.0001). Among patients who had no record of definitive treatment, AAM had increased risk of distant metastasis (aHR = 1.26, 95% CI, 1.15–1.39, P = 0.002). However, AAM who received definitive treatment, particularly radiotherapy, showed overall improvement in distant metastasis compared to EAM (aHR = 0.86, 95% CI, 0.81–0.93, P < 0.0001). This comprehensive analysis reveals a national-level PCa incidence disparity in a relatively equal access-to-care network. AAM display a higher burden of both localized and metastatic PCa, placing them at a higher risk of adverse outcomes across the PCa continuum. Consequently, timely diagnosis and equitable treatment delivery are likely critical factors for reducing disparities in disease outcomes.