Women diagnosed with breast cancer may have a higher risk of a type of heart problem called atrial fibrillation, according to a retrospective Danish study.
The research was published online in the journal HeartRhythym on Jan. 28, 2019. Read the abstract of “Incidence of atrial fibrillation in conjunction with breast cancer.”
Atrial fibrillation, also called AFib, is a fluttering or irregular heartbeat. Atrial fibrillation can lead to blood clots, stroke, heart failure, and other heart diseases.
Along with surgery, treatments such as radiation, chemotherapy, targeted therapies, and hormonal therapy medicines make breast cancer treatable. Still, because the treatments have unavoidable effects on healthy cells as well as cancer cells, there are pros and cons associated with each treatment. One possible side effect is heart damage. Other research has shown that heart disease is the leading cause of death among women who have been diagnosed with early-stage breast cancer.
A retrospective study means the researchers analyzed information that was collected before the study was designed. Some doctors think that the results of retrospective studies aren’t as strong as those from studies that are designed first and then collect new information specifically for that study.
How the study was done and results
To do the study, the researchers used national health records in Denmark to identify 74,155 women who had been diagnosed with breast cancer between 1998 and 2015.
The researchers matched by age the 74,155 women who had been diagnosed with 222,465 women from the general population of Denmark who had not been diagnosed with breast cancer. They then analyzed and compared the rates of atrial fibrillation in the two groups.
Overall, women who had been diagnosed with breast cancer had a higher risk of atrial fibrillation compared to women who had not been diagnosed with breast cancer.
- Women who were younger than 60 years old were more than twice as likely than average to develop atrial fibrillation in the 6 months after being diagnosed with breast cancer. These women had an 80% higher risk of developing atrial fibrillation from 6 months to 3 years after being diagnosed with breast cancer.
- Women who were older than 60 had an average risk of atrial fibrillation in the 6 months after being diagnosed with breast cancer. These women had a 14% higher risk of developing atrial fibrillation from 6 months to 3 years after diagnosis.
“This study was the first to show that women with recent breast cancer had an increased risk of developing atrial fibrillation,” said lead investigator Maria D'Souza, M.D., of the Cardiology Department of the Herlev and Gentofte Hospital in Hellerup, Denmark. “Our findings should encourage doctors to focus on the risk of atrial fibrillation in patients with recent breast cancer in order to diagnose and treat as early as possible, and researchers to search for increased risk of atrial fibrillation looking at the cancer itself, treatment, genetic predisposition, and shared life style risk factors. Ultimately, earlier treatment may result in better stroke prevention.”
What this means for you
While the results of this study are troubling, it’s important to know the researchers didn’t account for women who may have had heart problems or other conditions that could affect heart function before they were diagnosed with breast cancer. The researchers also didn’t account for other risk factors that are linked to both breast cancer and heart disease, such as being overweight, smoking, and drinking alcohol.
It’s also important to know that doctors are very aware that certain breast cancer treatments, such as anthracycline chemotherapy medicines and the targeted therapy Herceptin (chemical name: trastuzumab), can cause heart problems. In many cases, doctors will recommend you have heart function testing before you start breast cancer treatment.
If you’ve been diagnosed with breast cancer and have a history of heart problems, it’s a good idea to talk to your doctor about your risk of treatment-related heart issues and how your heart function will be monitored during and after treatment.
If you’ve been diagnosed with breast cancer and don’t have a history of heart problems, but anthracycline chemotherapy and/or Herceptin will be part of your treatment plan, you also may want to ask your doctor about your risk of treatment-related heart issues and how your heart function will be monitored during and after treatment.
In either case, you also may want to ask if visiting a cardiologist before breast cancer treatment starts is a good idea for you. The cardiologist can evaluate your heart function and decide if you’re at high risk for developing heart disease or heart failure from breast cancer treatment.
Together, you can decide on the best treatment and monitoring plan for your unique situation.
Written by: Jamie DePolo, senior editor
Reviewed by: Brian Wojciechowski, M.D., medical adviser