As reported in The Lancet Oncology by Lund et al, a Danish prospective cohort study showed no increased risk of ischemic cardiotoxicity with use vs no use of aromatase inhibitor treatment in postmenopausal patients with early-stage breast cancer.
Study Details
The study included identification of postmenopausal patients of any age diagnosed with breast cancer from the nationwide Danish Breast Cancer Cooperative Group (DBCG) clinical database between January 2009 and December 2020, with linkage to other nationwide registries. The patient cohort was stratified according to a history or no history of selected cardiovascular disease (defined as ischemic heart disease, ischemic stroke, and heart failure). The primary outcome measure was two-point major adverse cardiovascular events (MACEs), consisting of acute myocardial infarction or ischemic stroke.
Key Findings
Among 43,440 postmenopausal patients identified with a diagnosis of breast cancer, 32,635 had follow-up and were included in the analysis.
Among 29,118 patients with no history of selected cardiovascular disease, 510 two-point MACEs were observed among 22,135 patients who received aromatase inhibitor treatment (incidence rate = 4.3/1,000 person-years of follow-up), and 170 two-point MACEs were observed among 6,983 patients who did not receive aromatase inhibitor treatment (incidence rate = 4.1/1,000 person-years). The adjusted hazard ratio (HR) for MACEs for the aromatase inhibitor treatment group vs the no aromatase inhibitor treatment group was 0.91 (95% confidence interval [CI] = 0.73–1.14).
Among 3,517 patients with a history of selected cardiovascular disease, 158 two-point MACEs were observed among 2,661 patients in the aromatase inhibitor treatment group (incidence rate = 12.4/1,000 person-years), and 50 two-point MACEs (incidence rate = 12.1/1,000 person-years) were observed among 856 patients in the no aromatase inhibitor treatment group (adjusted HR = 0.81, 95% CI = 0.58–1.15).
The investigators concluded: “Our findings do not support a clinically relevant ischaemic cardiotoxic potential of aromatase inhibitor treatment in patients with early breast cancer and do not support avoiding aromatase inhibitor treatment prescription in patients with early breast cancer.”
Marie Lund, PhD, of the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, is the corresponding author of The Lancet Oncology article.
Disclosure: The study was funded by Bispebjerg and Frederiksberg Hospital, Kræftens Bekæmpelse, Fonden til Lægevidenskabens Fremme, and others. For full disclosures of the study authors, visit thelancet.com.
