Nurses Should Explore the Value of Cardiac Monitoring Among Younger Breast Cancer Survivors

For the 10% of patients with breast cancer who are diagnosed before the age of 45, there’s good news and bad news.

The good news is that more advanced treatments have brought the 5-year survival rate to about 90%, with a likelihood of long-term survival.

The bad news is that those treatments increase the risk for heart problems to develop in the years ahead.

Oncology nurses know that anthracycline chemotherapies, the targeted drug Herceptin (trastuzumab), and radiation therapy — all used to treat breast cancer — can increase the risk of cardiovascular disease. In fact, survivors of breast cancer are 3 times more likely to develop heart problems than people who have never had cancer.

Yet, clinical practice guidelines do not recommend long-term heart screening or monitoring for survivors of breast cancer, according to the authors of a poster presented at the 43^rd Annual Oncology Nursing Society Congress, held May 17 to 20 in Washington, D.C.

Such screening is recommended for survivors of pediatric cancers, another group likely to live for many years and, during that time, potentially develop adverse effects. Yet, research in cardio-oncology focuses on older cancer survivors, rather than on the more than 350,000 who received their breast cancer diagnoses before age 45, said Jacqueline B. Vo, BSN, RN, and a PhD candidate in the School of Nursing at the University of Alabama at Birmingham.

That’s why research is needed to determine whether specialized cardiac screening should also be recommended for survivors of younger-adult breast cancer, Vo said.

She and her co-authors took a first step by determining which cardiac risk factors are present among younger adults with breast cancer that could be exacerbated by treatment. The researchers reviewed the electronic medical records of 152 women who were free of cardiovascular disease but diagnosed with various breast cancer subtypes between ages 30 and 44. The women had stages I to III cancer and were diagnosed between 2012 and 2015, according to the records provided by an academic medical center in Alabama.

In analyzing patient data, the team considered demographics, survivorship characteristics and cardiovascular disease risk variables, such as obesity, smoking and blood pressure status. This information was logged at diagnosis and again two years later.

Among participants, most of whom were Caucasian, the average age at breast cancer diagnosis was 39 years. Seventy-four percent were married and 72% employed. Eighty-three percent received treatments the researchers classified as chemotherapy (43% taking anthracyclines and 26% taking Herceptin). Sixty-five percent underwent radiation therapy and 99% had surgery.

Participants were overweight at baseline, and at follow-up, researchers found that they had experienced a statistically significant increase in body mass index (27.9 kg/m2 vs. 29 kg/m2). The investigators’ measurements did not reveal a significant increase in hypertension, but the number of women taking medicine for the condition had doubled by the two-year follow-up, Vo said.

Smoking among participants decreased from 18% to 13%, but that did not represent a statistically significant difference.

The biggest change was in the rate of menopause, which rose sharply, from 13.8% at baseline to 40.1% at follow-up. Likely, this was because some women were put into medically induced menopause as part of their treatment, Vo said. She called menopause “a huge risk factor for cardiovascular disease.”

“This study demonstrates that young breast cancer survivors may be at increased cardiovascular disease risk, with poor underlying … risk profiles combined with receiving cardiotoxic treatments,” the authors wrote in an abstract. “Additionally, the cardiovascular disease risk may increase over time.”

The researchers posited that special cardiac recommendations for this population of survivors may need to be added to existing guidelines. These could be helpful, the nurse scientists argued, since early identification of heart problems has been shown to improve their prognosis. However, without more research, there will not be enough data to support a recommendation for long-term heart screening in these survivors, the team stated in the poster.

“Current adult cancer clinical guidelines may not be applicable, as young breast cancer survivors may have similar cardiovascular late effects to pediatric cancer survivors, who also have long survivorship periods,” they wrote in the abstract. “There is a need to generate nursing research focused in cardiovascular disease risk in young breast cancer survivors to improve survivorship care.”

To best facilitate this study, the team suggested that “collaborations between oncology and cardiac nurses are important in both practice and research to establish a better understanding of cardiovascular risk profiles and identify impactful interventions geared toward young breast cancer survivors.”

A next study, they said, will look more closely at the cardiovascular risk associated with breast cancer treatments in this population of survivors. Vo hopes to follow patients for 10 or 15 years and track any cardiovascular incidents.

In the meantime, Vo recommended that survivors of younger-adult breast cancer learn and watch for the signs and symptoms of heart problems or failure, such as shortness of breath and fatigue, and always go to their follow-up appointments, where health care practitioners may keep tabs on their heart health.

Reference:

Vo JB, Dheeraj R, Landier W, et al. Examining the link between breast cancer and cardiovascular disease risk in young survivors. Presented at: 43^rd Annual Oncology Nursing Society Congress; May 17-20, 2018; Washington, D.C. Poster IS30. https://ons.confex.com/ons/2018/meetingapp.cgi/Paper/3752