A number of studies have shown that women treated for breast cancer have a higher risk of heart problems compared to women who haven’t been treated for breast cancer. Now, the most recent study finds that the risk of recurrent breast cancer and death due to breast cancer may increase in people who had a heart attack, stroke or heart failure after being treated for early-stage breast cancer.
There are many types of chemotherapy, but one very common and effective type is the anthracycline doxorubicin. But according to the Oregon Health and Science University’s Center for Women’s Health, part of how it works is by binding to cancer cells' DNA to stop them from replicating. This is great for treating breast cancer, but anthracyclines can cause irreversible damage to the heart.
So, let’s take a look at the study, what the researchers did, and what they found.
Researchers at the New York University School of Medicine studied 1,724. Within the group, 270 people had some type of heart problem in the years after being diagnosed with breast cancer. Researchers say they found that people who had a heart attack, stroke or heart failure were nearly 60% more likely to have a cancer recurrence compared to people who did not have heart problems after a breast cancer diagnosis.
The researchers also looked to see whether having heart problems affected a person’s risk of dying from breast cancer. Of the 1,544 people included in that analysis, 168 had some type of heart problem in the years after being diagnosed with breast cancer. Compared to people who did not have heart problems after a breast cancer diagnosis, people who had a heart attack, stroke or heart failure were 60% more likely to die from breast cancer.
The researchers also found that having a heart attack altered the expression of 235 genes in immune system cells. When a gene’s expression is changed, it changes the way the gene functions. In particular, genes involved in stopping the development of cancer cells were suppressed. Researchers think having a heart attack may reprogram the genes, but this was an animal study, and more research needs to be done.
One of the co-authors of the study says it’s very important for breast cancer survivors to understand that there is a link between breast cancer and heart disease. Breast cancer survivors are at increased risk for heart disease.
Another study found that besides cancer itself, heart disease was the most common cause of death among women who were diagnosed with breast cancer. Within 10 years of being diagnosed, the most common cause of death was heart disease, followed by cerebrovascular disease (such as a stroke or blood clot). After 10 years, the most common non-cancer cause of death was heart disease and Alzheimer’s disease. In fact, it’s important to remember that heart disease remains the No. 1 killer among men and women in the United States.
If you’re a breast cancer patient or are undergoing treatment for breast cancer, knowing that those treatments may increase your risk of cardiovascular disease is the first step to achieving better heart health.
Living a healthy lifestyle that includes regular blood pressure checks, a Mediterranean-style diet, and exercise can help soften the side effects of breast cancer treatment. But it’s only the beginning.
Researchers recommend that all breast cancer survivors talk to their doctor about closely monitoring for cardiovascular risk factors.
You can learn more about screenings like these in our guide: “Cardiology Tests That Are Helping Healthy Hearts Stay Healthy.” The guide includes information on one screening that can actually predict your risk for heart attack over the next decade.