Association of census tract-level socioeconomic status with disparities in prostate cancer-specific survival.

BACKGROUND: Social determinants of prostate cancer survival and their relation to racial/ethnic disparities thereof are poorly understood. We analyzed whether census tract-level socioeconomic status (SES) at diagnosis is a prognostic factor in men with prostate cancer and helps explain racial/ethnic disparities in survival.
METHODS: We used a retrospective cohort of 833 African American and white, non-Hispanic men diagnosed with prostate cancer at four Chicago area medical centers between 1986 and 1990. Tract-level concentrated disadvantage (CD), a multidimensional area-based measure of SES, was calculated for each case, using the 1990 U.S. census data. Its association with prostate cancer-specific survival was measured by using Cox proportional hazard models adjusted for case and tumor characteristics, treatment, and health care system [private sector vs. Veterans Health Administration (VA)].
RESULTS: Tract-level CD associated with an increased risk of death from prostate cancer (highest vs. lowest quartile, HR = 2.37, P < 0.0001). However, the association was observed in the private sector and not in the VA (per 1 SD increase, HR = 1.33, P < 0.0001 and HR = 0.93, P = 0.46, respectively). The multivariate HR for African Americans before and after accounting for tract-level CD was 1.30 (P = 0.0036) and 0.96 (P = 0.82), respectively.
CONCLUSIONS: Census tract-level SES is a social determinant of prostate-specific mortality and helps account for racial/ethnic disparities in survival. An equal-access health care system may moderate this association. IMPACT: This study identifies a potential pathway for minimizing disparities in prostate cancer control. The findings need confirmation in a population-based study. ©2011 AACR