Investigating cardiovascular diseases related to endocrine therapy in hormone receptor-positive early breast cancer: insights from a nationwide real-world study.

Background: Breast cancer (BC) patients face abnormal lipid metabolism and increased cardiovascular disease (CVD) risk due to endocrine therapies (ETs). This study evaluates CVD incidence and lipid abnormalities in Chinese patients with early-stage hormone receptor-positive (HR+) BC to inform personalized treatments.

Methods: Data from female patients aged 18-80 years with stage I-III HR + BC registered in the National Cancer Center Oncology Information Database (NCCOID) (2013-2018) were analyzed. Outcomes included lipid profile changes, CVD incidence, and five-year survival rates.

Results: Among 11,537 patients, ETs significantly disrupted lipid metabolism, increasing abnormal total cholesterol, triglycerides, LDL-C, and HDL-C levels. Nonsteroidal aromatase inhibitors (NSAI) ± ovarian function suppression (OFS) led to the largest increase in abnormal total cholesterol (10.26 to 17.32%), while selective estrogen receptor modulators (SERM) ± OFS caused the greatest rises in triglycerides (16.07 to 25.86%), LDL-C (12.11 to 23.34%), and HDL-C (10.86 to 17.23%). Only 3.82% of patients received lipid-lowering therapy. ETs were associated with higher CVD incidence, including hypertension, myocardial infarction, and atrial fibrillation, but five-year survival rates did not differ significantly across ET regimens (P > 0.05).

Conclusion: ETs may be associated with alterations in lipid metabolism and a potential increase in CVD risk in early-stage HR + BC patients. These findings highlight the relevance of enhanced lipid monitoring and cardiovascular risk management to support optimized treatment outcomes in the Chinese population.