Insurance status and racial disparities in cancer-specific mortality in the United States: A population-based analysis

Background: Cancer-specific mortality (CSM) is known to be higher among blacks and lower among Hispanics compared with whites. Private insurance confers CSM benefit, but few studies have examined the relationship between insurance status and racial disparities. We sought to determine differences in CSM between races within insurance subgroups. Methods: A population-based cohort of 577,716 patients age 18 to 64 years diagnosed with one of the 10 solid malignancies causing the greatest mortality over 2007 to 2012 were obtained from Surveillance, Epidemiology, and End Results. A Cox proportional hazards model for CSM was constructed to adjust for known prognostic factors, and interaction analysis between race and insurance was performed to generate stratum-specific HRs. Results: Blacks had similar CSM to whites among the uninsured [HR = 1.01; 95% confidence interval (CI), 0.96-1.05], but higherCSMamong the Medicaid (HR=1.04; 95% CI, 0.01-1.07) and non-Medicaid (HR = 1.14; 95% CI, 1.12-1.16) strata. Hispanics had lower CSM compared with whites among uninsured (HR = 0.80; 95% CI, 0.76-0.85) and Medicaid (HR = 0.88; 95% CI, 0.85-0.91) patients, but there was no difference among non-Medicaid patients (HR = 0.99; 95% CI, 0.97-1.01). Asians had lower CSM compared with whites among all insurance types: uninsured (HR = 0.80; 95% CI, 0.76-0.85), Medicaid (HR = 0.81; 95% CI, 0.77-0.85), and non-Medicaid (HR = 0.85; 95% CI, 0.83-0.87). Conclusions: The disparity between blacks and whites was largest, and the advantage of Hispanic race was absent within the non-Medicaid subgroup. Impact: These findings suggest that whites derive greater benefit from private insurance than blacks and Hispanics. Further research is necessary to determine why this differential exists and how disparities can be improved.