Cardiovascular risk after breast cancer chemotherapy in a hospital-based real-word study from Northwest China

Background Cardiotoxicity is a common adverse effect of chemotherapy in breast cancer, yet real-world evidence, particularly from Asian populations remains limited. Methods Using inpatient and outpatient hospital records from a major tertiary hospital centre in Xi’an, Northwest China, we tested three commonly prescribed chemotherapy regimens: Anthracyclines plus Cyclophosphamide (A+C; reference), Docetaxel plus Cyclophosphamide (D+C), and Docetaxel plus Carboplatin (D+Cb). Their associations with cardiovascular outcomes, including cardiovascular disease (CVD) accumulation measured by the number of distinct cardiovascular diagnoses, and incident CVD risk were evaluated. Models were adjusted for patient characteristics, targeted and endocrine treatments, and baseline CVD risk factors. Results We identified 8672 breast cancer patients with at least one medication record. After a median follow-up of 3.2 years, 14% (n=1194) of patients developed at least one CVD event. Compared with A+C, neither D+C nor D+Cb was associated with incident CVD or specific cardiovascular outcomes. Within the first-year follow-up, patients receiving D+C showed a lower CVD accumulation (Beta=-0.34, p=0.041), and reduced risks of incident CVD (HR = 0.70, p=0.034) and cerebrovascular diseases (HR = 0.20, p=0.037) at nominal significance but did not survive after multiple testing correction. Additional adjustment for clinical stage and radiotherapy yielded no associations between chemotherapies and cardiovascular outcomes. Conclusions Compared with A+C, D+C or D+Cb were not associated with cardiovascular outcomes. Patients treated with D+C potentially showed reduced risk of overall cardiovascular disease and cerebrovascular disease incidence within one year, with more evidence needed.