The Heart of the Matter: Unraveling the Link Between CVD and Breast Cancer for American Heart Month

Recent research and additional needed studies further exploring the connections between breast cancer and cardiovascular disease (CVD) are critical as more than 120 million people are living with a cardiovascular condition in America and heart disease is the leading cause of death worldwide, according to Amy M. Ahnert, MD.1,2

More links between the 2 diseases are being uncovered with a recent study showing there were statistically significantly increased odds that patients with locally advanced or metastatic breast cancer at diagnosis had prevalent CVD (OR, 1.10; 95% CI, 1.03-1.17; P = .007).3 The odds were also directionally consistent when separately examining patients with locally advanced (OR, 1.09; 95% CI, 1.02-1.17; P = .02) and metastatic (OR, 1.20; 95% CI, 0.94-1.54; P = .15) disease.

“Heart disease is the number one cause of death in women, and we have an obligation to speak to our patients and to focus on prevention whether we have a patient that’s in front of us with a breast cancer diagnosis, CVD diagnosis, or both,” said Ahnert, director of the Women’s Heart Program at Morristown Medical Center and a cardiologist at Atlantic Health System in New Jersey. “We have to spend the time and the effort to help them to make sure that they’re living their healthiest life because diet, exercise, not smoking, and maintaining a healthy weight are going to be important in terms of lifelong prevention of both cancer and heart disease.”

This February for American Heart Month, Ahnert sat down with OncLive® and highlighted newer shared risk factors to be aware of between CVD and breast cancer, as well as questions regarding personalized screening for the diseases.

OncLive: What is most important for doctors to know regarding newly investigated shared risk factors between CVD and cancer?

Ahnert: As a cardiologist, no matter what audience I’m speaking to, I always remind them that heart disease is the number one killer of women. It is important for oncologists to know that there is a lot of progress in the cardiovascular space and more attention [to] and better understanding [of] unique cardiovascular risk factors for women.

Many know what the standard “traditional” risk factors are for CVD [including] smoking, obesity, diabetes, high blood pressure, and family history, but there’s a whole new realm of nontraditional cardiovascular risk factors that are unique to women. Some of these are pregnancy-related conditions [such as] high blood pressure in pregnancy, preeclampsia, and gestational diabetes. Over the past 10 to 15 years there have been studies showing that women who’ve experienced these pregnancy outcomes have a 2-to-3-fold increased risk of developing CVD. There are many cardiologists, I would say, who aren’t aware of this. It is important to have oncologists be aware of these risk factors, including autoimmune diseases and rheumatologic conditions [such as] lupus and rheumatoid arthritis as well.

[Regarding] next steps and future prospective trials, I would love to see them be more comprehensive looking at all those unique risk factors in women because maybe there’s another connection. [With] some of these risk factors and pregnancy-related outcomes that increase the risk of CVD, maybe there’s something there that’s ultimately going to [help us] better understand the connection between CVD and breast cancer. [Ongoing research such as one study from JAMA Network Open is] exciting to me because we’re broadening the scope; we’re looking at women and looking in a more comprehensive way and trying to get a better understanding of relationships between diseases that are unique to women.

In your practice as a cardiologist, how often do you see links between CVD/heart health and cancer?

We see it if we ask. We can’t be blind. My approach when I’m taking care of women is that I make sure I’m taking a very expansive and thorough history. I need to know if they’ve had cancer history, breast cancer history, and potential treatments that would be toxic for future development of CVD. I also need to understand their pregnancy history.

The other [area] where I see links is that I have a lot of patients who come to see me for consultation regarding safety of hormone replacement therapy. I have patients who are having menopausal symptoms and want to start hormone replacement therapy. They ask, ‘Can I be on it, is it safe?’ I work with them to devise whether it’s safe for them, not only for future cardiovascular risk, but for breast cancer risk. I see this in my practice, but it’s because I make it a priority and an effort to make sure that I’m looking at the whole patient. In the end, we have to [lose] our blinders and look at patients with a broader lens.

Should personalized screening approaches be advised for patients with CVD?

We don’t know yet, and that’s a big question. Do we need to now say ‘If you have CVD, we need to start screening earlier or utilize different types of screening for breast cancer and more advanced types of breast cancer?’ We can’t make that leap yet, but it is so imperative as health care practitioners that we remember screening and prevention for CVD and breast cancer. I spend a large part of my day-to-day talking to women about prevention. CVD is [largely] preventable—I’m not saying all breast cancer is preventable—but screening, early detection, preventive [measures], [and] good, healthy living is [beneficial] for prevention of both CVD and breast cancer.

Once we get further studies, we’ll have a better idea of the interplay. There may be a 2-way street [that may indicate] that women with breast cancer need to have earlier screening and detection for CVD and vice versa. We already are there in some respect because we do know women who’ve had breast cancer treatments [including] radiation, cardiotoxic chemotherapy, or chemotherapy that affects the heart, are [at increased risk]; we are or should be screening and treating them more aggressively for the potential of CVD. The next generation of studies will help us to know whether we’re ready to make that next step in terms of changing screening recommendations. I don’t believe we’re there yet.

References

1. American Heart Month: February 2024. United States Census Bureau. February 2024. Accessed February 11, 2025. https://www.census.gov/newsroom/stories/american-heart-month.html
2. The top 10 causes of death. World Health Organization. August 7, 2024. Accessed February 11, 2025. https://www.who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death
3. Angelov I, Haas AM, Brock E, et al. Cardiovascular disease and breast cancer stage at diagnosis. JAMA Netw Open. 2025;8(1):e2452890. doi:10.1001/jamanetworkopen.2024.52890