Long-term risk of congestive heart failure in younger breast cancer survivors: A nationwide study by the SMARTSHIP group

Background: There is a controversy about late-onset congestive heart failure (CHF) among breast cancer survivors. This study investigated the incidence rate and risk factors of late-onset CHF more than 2 years after the breast cancer diagnosis. Methods: A nationwide, retrospective study was conducted with the National Health Information Database. With 1:3 age- and sex-matched noncancer controls, Cox proportional hazard regression models were used to analyze the incidence and risk factors of late CHF. The cumulative incidence rate of late CHF was evaluated with a Kaplan-Meier analysis and a log-rank test. Results: A total of 91,227 cases (286,480 person-years) and 273,681 controls (884,349 person-years) were evaluated between January 2007 and December 2013. The risks of late CHF were higher in cases than controls (hazard ratio [HR], 1.396; 95% confidence interval [CI], 1.268-1.538). Younger survivors (age ≤ 50 years) showed a higher risk of late CHF than their younger counterparts (HR, 2.903; 95% CI, 2.425-3.474). Although older age was a risk factor for late CHF, older survivors (age ≥ 66 years) showed no difference in the risk of late CHF in comparison with their counterparts (HR, 0.906; 95% CI, 0.757-1.084). Anthracyclines and taxanes were risk factors for late CHF, although trastuzumab, radiation, and endocrine therapy were not. Conclusions: Young breast cancer survivors have a greater risk of late CHF than the young population without cancer. More attention should be paid to young breast cancer survivors who receive taxane- or anthracycline-based regimens over the long term.