Abstract PD10-09: Impact of insurance and socioeconomic status on clinical outcomes in therapeutic clinical trials for breast cancer

Background: Studies have shown an association between insurance status, socioeconomic status (SES) and disparities in clinical outcomes among breast cancer patients. The objective of this study was to evaluate insurance status and SES with respect to protocol treatment completion and survival among participants in two large randomized adjuvant breast cancer clinical trials. Methods: The data sources for this study were the ECOG-ACRIN (EA) clinical trials E1199 and E5103. An Agency for Healthcare Research Quality (AHRQ) SES index was calculated using zip codes from the trial patients’ residence and were linked to county level data on occupation, income, poverty, wealth, education and crowding. Insurance status at randomization was categorized into private, government (Medicaid, Medicare, and other government insurance), and self-pay. Logistic regression models and Cox proportional hazard models were used to estimate odds ratios [OR] and hazard ratios [HR] for the association between insurance type (government relative to private and self-pay relative to private) with protocol treatment completion (yes vs. no) and with overall survival respectively. The estimates reported here were adjusted for SES, race, age, tumor size, nodal status, hormone receptor status, and primary surgery at randomization. Preliminary analyses of individual government insurance types with outcome showed no difference in results versus using one combined ‘government’ insurance type category. Results: The study sample included 4954 patients from E1199 and 4836 patients from E5103. The majority of patients in E1199 and E5103 had private insurance 83.8% (4154/4954) and 82% (3987/4836) respectively. The median(range) SES index was 53.8 (41.8-66.8) for E1199 and 54.1(44.5-66.1) for E5013. Patients with government type insurance were less likely to complete treatment per protocol (OR (.95CI): E1199 0.73 (0.57-0.94), E5103 0.76 (0.64-0.91)) and had increased association with death (HR (.95CI):E1199 1.44 (1.22-1.70), E5103 1.29 (1.06-1.58)) compared to those patients with private insurance. Conversely, there was no association in completing treatment per protocol (E1199 1.03(1.01-1.06), E5103 1.14 (0.67-1.95)) or survival (E1199 1.00 (0.98-1.01), E5013 1.17(0.63-2.20)) between those patients who self-paid for care relative to those who were privately insured. There was no association between SES index and completing treatment per protocol (E1199 1.03(1.01-1.06), E5103 1.01 (0.99-1.03)) or survival (E1199 1.00(0.98-1.01), E5103 0.98(0.96-1.00)). Conclusions: In these two clinical trials, patients with government type insurance appeared to face barriers in trial treatment completion and had a lower survival compared to their privately insured counterparts. Future studies are encouraged to focus on patient and institution related variables that might be contributing to these insurance-based disparities in outcomes. Citation Format: Samilia Obeng-Gyasi, Anne O9Neil, Fengmin Zhao, Sheetal M Kircher, Timsina R Lava, Lynne I Wagner, Kathy D Miller, Joseph A Sparano, George W Sledge, Ruth C Carlos. Impact of insurance and socioeconomic status on clinical outcomes in therapeutic clinical trials for breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD10-09.