Breast Cancer Survivors At Increased Risk Of Heart Disease

Women receiving common treatments for breast cancer are at increased risk of several cardiovascular events, including stroke, heart attack and heart failure, according to a new study published in the Journal of Clinical Oncology.

9 of 10 women diagnosed with the disease now survive for at least 5 years after diagnosis, according to the American Cancer Society . But some of the therapies used to treat many patients are known to increase the risk of cardiovascular problems, although exactly why they do this and how is not currently well understood.

The new study looked at 13,624 women treated for invasive breast cancer at Kaiser Permanente in Northern California between 2005-2013. The women were compared to over 68,000 women without breast cancer, matching each study participant with breast cancer with 5 without of the same age and race/ethnicity. The study participants were followed for an average of 7 years post diagnosis, with the research finding that they were at much higher risk of cardiovascular events than the control participants without breast cancer.

“Cardiovascular disease, the leading cause of death among women in the U.S., is emerging as a major health concern of breast cancer survivors,” said Dr. Marilyn Kwan, a research scientist at the Kaiser Permanente Northern California Division of Research and senior author of the study. “This paper takes the additional step of reporting an association between treatments and the risk of cardiovascular disease itself,” Kwan added.

In particular, women who received two types of chemotherapy either alone, or in combination; anthracyclines and trastuzumab (also known as Herceptin) had the highest risk of cardiovascular complications. Those who received radiation therapy or another type of drug called aromatase inhibitor were also at increased risk compared to controls.

Cancer survivors are increasingly known to be at risk of other health problems, other than recurrence of their original cancer. Many of these come from the therapies used to treat their cancer and can include issues with the heart, lungs, hormones, neurological, fertility, pain and mental health. Despite this, survivorship care is not always accessible to many cancer survivors and when it is, comprehensive care and screening is not always provided.

“We hope to raise awareness that women who are breast cancer survivors must receive comprehensive, ongoing follow-up care and monitoring for cardiovascular risk,” said Heather Greenlee, N.D., Ph.D., M.P.H, a public health researcher at Fred Hutchinson Cancer Research Center in Seattle and lead author of the study. “Scientists and clinicians must prioritize research that will reduce this risk,” Greenlee added.