Differential Cardiovascular Outcomes of Each Antihypertensive Drug Class in Patients With Hypertension and Breast Cancer Undergoing Doxorubicin-Containing Chemotherapy

PURPOSE: The preemptive use of renin-angiotensin system (RAS) inhibitors may reduce doxorubicin (DOX)-related cardiotoxicity. Using the national insurance claims data of Korea, this study compared cardiovascular (CV) outcomes following the use of four major antihypertensive drug classes in patients with hypertension and breast cancer who underwent DOX-containing chemotherapy. METHODS: A total of 4,722 patients with hypertension and breast cancer who underwent DOX-containing chemotherapy were included. The outcomes were compared between patients who used RAS inhibitors, calcium channel blockers (CCBs), beta-blockers (BBs), and thiazide and thiazide-like diuretics (TDs). The primary outcome was a composite of incident heart failure and serious ventricular arrhythmias, including ventricular tachycardia and fibrillation, ischemic heart disease, and stroke. RESULTS: In the propensity score-matched population, there were no significant differences in the primary outcome between RAS inhibitor and CCB users; however, patients with diabetes who used CCBs had a worse primary outcome than those who used RAS inhibitors (adjusted hazard ratio [aHR], 1.93; 95% confidence interval [CI], 1.06-3.51). BB and TD users had a worse primary outcome compared with RAS inhibitor (aHR, 1.88; 95% CI, 1.30-2.71 in BB users and aHR, 2.55; 95% CI, 1.37-4.75 in TD users) or CCB (aHR, 1.54; 95% CI, 1.09-2.16 in BB users and aHR, 2.08; 95% CI, 1.13-3.82 in TD users) users. CONCLUSION: RAS inhibitors are preferred for the treating hypertension and improving CV outcomes in patients with hypertension and breast cancer undergoing DOX-containing chemotherapy, particularly in patients with comorbid diabetes. However, CCBs are equivalent to RAS inhibitors and are more favorable than BBs and TDs in terms of improving CV outcomes.