Le Nguyen, Avanceña Anton L V, Liu Yan, Shen Chan, Park Chanhyun
Health Outcomes Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA.
Health Outcomes Division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA; Department of Internal Medicine, Dell Medical School, The University of Texas at Austin, Austin, TX, USA.
J Geriatr Oncol. 2025 Sep;16(7):102333. doi: 10.1016/j.jgo.2025.102333. Epub 2025 Aug 6.
Racial disparities in cardiovascular (CV) outcomes among breast cancer (BC) survivors are well-documented. However, whether such disparities persist following anthracycline therapy, a common cardiotoxic treatment, remains unclear. We aimed to quantify racial disparities in the incidence of major adverse cardiac events (MACE) and examine the role of the Social Vulnerability Index (SVI) in mediating these disparities.
We conducted a retrospective cohort study using the 2007-2019 SEER-Medicare database. We included females aged ≥66 years with a new primary diagnosis of BC who received anthracyclines within one year after diagnosis. The index date was the initiation date of anthracyclines. The study exposure was race (Black vs. White), a socially constructed variable reflecting structural and institutional racism and encompassing multiple levels of health determinants. The primary outcome was the 10-year incidence of MACE. Associations between race and MACE incidence were evaluated using weighted proportional hazards models. Adjusted risk differences (aRD) were calculated as the difference in predicted 10-year risk-free probabilities between groups, based on the final adjusted models from the index date. Mediation analysis determined the contributions of SVI (county-level and theme-specific variables), BC-related characteristics, and clinical factors.
Among 5571 patients (22,154 person-years) who initiated anthracycline therapy, 2128 MACE events occurred. Black patients had a higher hazard of MACE (adjusted HR 1.2; 95% CI: 1.02 to 1.33), with a 10-year aRD of 2.3% (95% CI: 0.6% to 9.7%) compared to White patients. After adjusting for right-censoring, aHR was 1.3 (95% CI: 1.1 to 1.4) with a corresponding aRD of 7.8% (95% CI: 2.9% to 12.6%). Mediation analysis showed that the total percentage of mediation was 60.7 % (95% CI: 41.3% to 94.9%), primarily driven by clinical factors, which mediated 39.6% (95% CI: 25.7% to 64.3%). Hypertension, diabetes, anemia, obesity, and calcium-channel blocker use contributed considerably to the mediation.
MACE incidence was significantly higher in older Black patients with BC after initiating anthracycline therapy compared with their White counterparts. Clinical factors considerably mediated this racial disparity. Early interventions, enhanced cardiac surveillance, and targeted prevention strategies may help reduce inequities in CV outcomes among older women with BC receiving anthracycline therapy.
乳腺癌（BC）幸存者中心血管（CV）结局的种族差异已有充分记录。然而，在使用蒽环类药物治疗（一种常见的心脏毒性治疗方法）后，这种差异是否仍然存在尚不清楚。我们旨在量化主要不良心脏事件（MACE）发生率的种族差异，并研究社会脆弱性指数（SVI）在介导这些差异中的作用。
我们使用2007 - 2019年的SEER - Medicare数据库进行了一项回顾性队列研究。我们纳入了年龄≥66岁、新诊断为原发性BC且在诊断后一年内接受蒽环类药物治疗的女性。索引日期为蒽环类药物的起始日期。研究暴露因素是种族（黑人与白人），这是一个反映结构性和制度性种族主义且涵盖多个健康决定因素层面的社会构建变量。主要结局是MACE的10年发生率。使用加权比例风险模型评估种族与MACE发生率之间的关联。根据索引日期的最终调整模型，计算调整后的风险差异（aRD），即两组之间预测的10年无风险概率的差异。中介分析确定了SVI（县级和特定主题变量）、BC相关特征和临床因素的贡献。
在开始蒽环类药物治疗的5571例患者（22,154人年）中，发生了2128例MACE事件。黑人患者发生MACE的风险更高（调整后HR 1.2；95%CI：1.02至1.33），与白人患者相比，10年aRD为2.3%（95%CI：0.6%至9.7%）。在调整右删失后，aHR为1.3（95%CI：1.1至1.4），相应的aRD为7.8%（95%CI：2.9%至12.6%）。中介分析表明，中介的总百分比为60.7%（95%CI：41.3%至94.9%），主要由临床因素驱动，临床因素介导了39.6%（95%CI：25.7%至64.3%）。高血压、糖尿病、贫血、肥胖和使用钙通道阻滞剂对中介作用有很大贡献。
与白人患者相比，老年黑人BC患者在开始蒽环类药物治疗后MACE发生率显著更高。临床因素在很大程度上介导了这种种族差异。早期干预、加强心脏监测和有针对性的预防策略可能有助于减少接受蒽环类药物治疗的老年BC女性在CV结局方面的不平等。
