Cardiovascular Disease as a Leading Cause of Death in Breast Cancer Survivors
While breast cancer remains the most common cause of death overall in women with breast cancer (approximately 50% of deaths), cardiovascular disease is a significant competing cause, particularly in older women and long-term survivors 1.
Key Evidence-Based Facts
The data shows important nuances based on age and time since diagnosis:
In women diagnosed at age ≥66 years: Breast cancer causes 11.9% of deaths at 10 years, while cardiovascular disease causes 7.6% 1. However, for those who survive 5+ years after diagnosis, cardiovascular disease exceeds breast cancer as the leading cause of death 1.
Among women with pre-existing cardiovascular disease: Death rates from breast cancer and cardiovascular disease are equivalent for the first 5 years, after which cardiovascular deaths become more frequent (16.9% vs 14.6% at 10 years) 1.
Overall mortality breakdown: In a large population study, cardiovascular disease was the primary cause of death in 15.9% of breast cancer patients, followed closely by breast cancer itself at 15.1% 2.
Age matters significantly: Among women diagnosed at age <50, breast cancer accounts for 89% of deaths, but this drops to only 48% in women diagnosed at age ≥70 3.
The statement that "most" women with breast cancer die from heart disease is inaccurate—breast cancer remains the leading cause of death overall 1, 3. However, cardiovascular disease is indeed a critical competing risk that becomes the predominant cause of death in specific subgroups: older women, long-term survivors, and those with pre-existing cardiovascular conditions 4, 1.