Cardio-oncology disparities in breast cancer: mapping the social gradient of dual disease burden.

Breast cancer and cardiovascular disease (CVD) increasingly coexist as a major source of morbidity and mortality among survivors. As cancer survival improves, cardiovascular complications have emerged as a leading determinant of long-term outcomes, often exceeding cancer-related mortality. This dual disease burden is unevenly distributed, with marked disparities across race and ethnicity, socioeconomic status, geographic location, comorbid risk burden, and representation in clinical trials. Evidence demonstrates that historically marginalized populations experience higher cardiovascular mortality, greater treatment-related cardiotoxicity, and reduced access to preventive and specialty care. This review synthesizes current literature on cardio-oncology disparities and applies established frameworks-including intersectionality, structural racism, and syndemic theory-to explain how social and structural factors translate into adverse clinical outcomes. We highlight emerging clinical, community-based, and policy-level strategies aimed at promoting equitable cardiovascular survivorship for breast cancer patients.