Socioeconomic disparities in long-term heart failure risk of trastuzumab with or without anthracyclines in early-stage breast cancer: a SEER-Medicare database analysis

While it is well-established that cardiovascular disease and congestive heart failure (CHF) are increased among breast cancer survivors, little is known about how systemic therapy use, medical comorbidities, and socioeconomic factors interact to influence long-term cardiac outcomes. In this study, we performed an analysis of the SEER-Medicare database, including more than 200,000 patients with early-stage breast cancer. Using available zip code and census data, patient disease characteristics and cardiac outcomes were stratified by socioeconomic variables. Overall, patients of Black, Hispanic, and American Indian/Alaskan Native race/ethnicity had an increased incidence of large, high-grade tumors and nodal involvement as compared to White and Asian American/Pacific Islander (AAPI) patients. Lower per capita income (PCI), higher percentage of population living in poverty, lower level of education, and not speaking English at home were also associated with increased tumor size, grade, and nodal stage. Adjusting for cardiac covariates and cancer therapy type, a multivariate socioeconomic model revealed that Black patients had a higher risk of CHF and AAPI patients had a lower risk compared to White patients. Further adjusting for race/ethnicity, patients living in a zip code in the lowest quartile of PCI also had a higher risk of CHF compared to those in the highest quartile.