Breast cancer therapy and age difference in cardiovascular disease risks: A population-based cohort study in Taiwan.

OBJECTIVE

Cardiovascular events induced in breast cancer patients receiving radiotherapy (RT), chemotherapy (CT), or a combination of both (CRT) can increase the risk of death. This nationwide population-based study aims to estimate the risk of cardiovascular complications with a follow-up period of 5 years.

MATERIALS AND METHODS

The study cohorts consisted of all patients hospitalized with a principal diagnosis of breast cancer who underwent treatment in 2002. The Cox proportional hazard model and Kaplan-Meier plot were analyzed to compare the cardiovascular event-free survival rate among breast cancer patients treated with different modalities.

RESULTS

Of the 5514 breast cancer patients identified, 289 patients had cardiovascular disease (CVD): 110 (5.7%) from the surgery-alone group, 24 (4.1%) from the RT group, 79 (4.6) from the CT group, and 76 (5.8%) from the CRT group. Breast cancer patients who undergo CT and CRT at an age less than 55 years had a higher risk of CVD when compared with the surgery-alone group (for both groups, p < 0.001). By contrast, breast cancer patients aged over 55 years had no increased risk of CVD among the different treatment modalities.

CONCLUSION

Breast cancer patients receiving CT and/or CRT have a higher risk of CVD, especially younger patients (aged < 55 years). Therefore, regular examinations of cardiac functions and electrocardiogram should be considered in cases of young breast cancer patients who are receiving CT and/or CRT.