Relative Risk of Cardiovascular Mortality in Breast Cancer Patients: A Population-Based Study

To investigate the risk of cardiovascular disease (CVD) mortality in breast cancer patients compared with the general female population. Data was retrieved from the Surveillance, Epidemiology, and End Results database. 924,439 female breast cancer patients who were at the age of follow-up 30 years and diagnosed during 1990-2016 as well as the aggregated general female population in the US were included. Using multivariable Poisson regression, we calculated incidence rate ratios (IRRs) of CVD mortality among female breast cancer patients compared with the female population. The risk of CVD mortality was mildly increased among breast cancer patients at the age of follow-up 30-64 years (IRR 1.06, 95% confidence interval [CI] 1.03-1.10) compared with the general population. This growth of risk reached its peak within the first month after diagnosis (IRR 3.33, 95% CI 2.84-3.91) and was mainly activated by diseases of the heart (IRR 1.11, 95% CI 1.07-1.15). The elevation was greatest in survivors at the age of follow up 30-34 years (IRR 3.50, 95% CI 1.75-7.01). Clinicians should provide risk mitigation strategies with early monitoring of CVD mortality for breast cancer survivors, especially those who were young or with aggressive tumor stage.