Hormone Cancer Therapies Increase CV Risk: AHA Scientific Statement

A new American Heart Association scientific statement is highlighting the potential long-term cardiovascular effects of hormonal therapies used in patients with certain cancers.

“Hormone-dependent cancers such as breast and prostate cancer are the most common noncutaneous cancers in women and men both in the United States and worldwide,” the document points out, adding that as patients with these cancers “continue to live longer, CVD has emerged as a leading cause of mortality and morbidity among survivors.”

Unlike chemotherapy, which produces obvious side effects, treatments like aromatase inhibitors, selective estrogen-receptor modulators, and androgen deprivation therapy that target hormones can be easier for clinicians to overlook, lead author Tochi Okwuosa, DO (Rush University Medical Center, Chicago, IL), told TCTMD.

“We need to be aware that they increase cardiovascular risk,” she stressed. “Also, when patients have baseline cardiovascular risk factors like high blood pressure, high cholesterol, smoking history, and diabetes, they are at higher risk for having side effects as a result of these hormonal therapies. On the other hand, hormonal therapies increase the risk of these cardiovascular risk factors. And so, when you combine all of that, that increases downstream risk of cardiovascular disease in these patients.”

Okwuosa said the statement, published online today in Circulation: Genomic and Precision Medicine, is a “call to arms” for investigation in this field to further define how hormonal treatments, which are often prescribed for the rest of a patient’s life, are linked to cardiovascular health.

“We need specific randomized controlled trials comparing these hormonal therapies and their individual nuanced effects and also particularly studying cardiovascular outcomes [as well as] the effects of the duration,” she specified. “So, if you treated them with aromatase inhibitors for 5 years for breast cancer versus treated them for 10 years, does that make a difference in cardiovascular risk?”

The statement also stresses the need for future research looking into racial and ethnic disparities among cancer patients who have received hormonal therapy.

Okwuosa stressed one point of clarification. “We're definitely not saying ‘Don't place patients on hormonal therapy,’” she said. Rather, the goals are “just to be aware of the [increased risks] and to manage them accordingly.”

As for how to move forward in these patients, she advised in a press release that “for patients who have two or more cardiovascular risk factors, it is likely that referral to a cardiologist would be appropriate prior to beginning hormone treatment. For patients already receiving hormonal therapies, a discussion with the oncology team can help to determine if a cardiology referral is recommended.”

Also, the burgeoning field of cardio-oncology has been rising to meet these patients at the crossroads of two serious diseases, and specialists in this field should be consulted for optimal care on both fronts, the authors say.

“Patients with cancer who also have a history of or multiple risk factors for CVD may be referred to cardiology or cardio-oncology clinics in addition to following up with their oncologists for cancer care. Similarly, patients with preexisting insulin resistance or frank diabetes may benefit from care coordinated with an endocrinologist, in addition to ongoing cancer care,” they write, adding, “Most important, patient involvement and education at the outset of treatment will continue be a cornerstone of the care model. Multidisciplinary therapeutic alliances with patients help to maintain the behaviors necessary for comorbidity control and detection of evolving cardiovascular complications.”