Treatment at Academic Centers Decreases Insurance-Based Survival Disparities in Colon Cancer

Abstract

Background: Although insurance and race-based survival disparities in colon cancer are well studied, little is known regarding how these survival disparities are impacted by type of treating facility.

Materials and methods: This is a retrospective cohort study of 433,997 patients diagnosed with colon adenocarcinoma using the National Cancer Database (NCDB). Using Cox proportional hazard analyses, we assessed overall survival (OS) as a function of race, insurance status, and treating facility, after adjusting for demographic and clinical factors. We also assessed differences in OS according to race and insurance status stratified by treating facility type.

Results: OS was significantly diminished for blacks (hazard ratio [HR], 1.09; 95% confidence interval [CI], 1.07-1.10; P < 0.001) and increased for patients of other race (primarily Asians; HR, 0.76; 95% CI, 0.74-0.78) compared with whites. Patients with private insurance had improved OS compared with uninsured (HR, 1.28; 95% CI, 1.25-1.31; P < 0.001), Medicaid (HR, 1.35; 95% CI, 1.33-1.38; P < 0.001) and Medicare (HR, 1.13, 95% CI, 1.12-1.15; P < 0.001) patients. Compared with patients treated at comprehensive community programs, patients treated at academic centers (ACs) had improved OS (HR, 0.86; 95% CI, 0.85-0.88; P < 0.001). When stratified by type of treating facility, racial disparities were not mitigated for patients treated at ACs compared with other facilities (P = 0.266 for interaction). At ACs, patients with Medicaid had persistent OS disparities compared with patients with private insurance (HR, 1.12; 95% CI, 1.09-1.15; P < 0.001), although these disparities were significantly diminished compared with patients treated at other facilities (HR, 1.41; 95% CI, 1.38-1.45; P < 0.001).

Conclusions: Other race, private insurance, and treatment at AC were independently associated with improved OS in patients with colon cancer. Medicaid-based, but not race-based, survival disparities are reduced at ACs compared with other facilities.

Keywords: Colon cancer; Health care disparities; Health care facilities; Insurance status; Race.