Survival disparities in top five cancers in the United States: A population based study.

Abstract

e18545 Background: Health inequity is an important field in cancer research and it is vital to determine the underlying etiologies to eliminate health disparities. Health insurance differences in survival outcomes have been reported for patients residing in California and New Jersey. Likewise, we aim to explore the impact of variations in insurance status and demographic factors on survival outcomes in patients with the top five cancers in the United States using a nationwide cancer registry. Methods: Surveillance, Epidemiology, and End Results (SEER) 18 program was queried to identify patients with a primary diagnosis of lung, breast, colorectal, prostate cancer, and melanoma from 2007 to 2016. Patient characteristics included are age (≥20 years), sex, marital status, metropolitan or non- metropolitan residence, insurance status (private vs. Medicaid vs. uninsured), education level, stage at diagnosis, and survivals. Descriptive and survival analyses were performed using Pearson Chi-square, Kaplan-Meier and Cox regression tests. Results: A total of 935,916 patients were included, of which 344,022 (37%) had breast cancer, 209,762 (22%) prostate cancer, 151,553 (16%) colorectal cancer, 151,468 (16%) lung cancer, and 79,111 (8%) melanoma. Most patients were aged > 50 years (76%) and 55% were female. Privately insured accounted for 83% of all patients, 13% had Medicaid and 4% were uninsured. Male gender, married, patients with higher education level, residing in metropolitan areas were more likely to have private insurance (p < 0.001) compared to female gender (84.3% vs. 81.2%), unmarried (90.1% vs. 68.7%), subjects with very low to moderate education level (88.2% vs. 80.8%), and ones residing in non- metropolitan areas (83.4% vs. 76.3%). Patients with private insurance were more likely to be diagnosed at localized stage compared to Medicaid insured and uninsured (59.2% vs. 38.2% and 36.6%; p < 0.001). On bivariate and multivariate analyses across of all five cancers, age > 50 years (HR 2.0; p < 0.001), male gender (HR 1.3; p < 0.001), single (HR 1.3; p < 0.001), Medicaid insurance (HR 1.2; p < 0.001), and uninsured (HR 1.3; p < 0.001) were associated with worse overall survival than age < 50 years, female, unmarried, and privately insured. Conclusions: Along with noticeable survival disparities by insurance status in lung, breast, colorectal, prostate and melanoma, we noted that privately insured patients are more likely to be presented at an earlier stage compared to patients with Medicaid and uninsured. Additionally, elderly age, lower education level, unmarried and low socioeconomic status had a negative impact on survival. Multidisciplinary care team efforts are critical in mitigating these health disparities.