Department of Research & Evaluation News

Researchers have developed a new risk calculation model to help predict the risks of heart problems for breast cancer survivors. Their research was published in JAMA Oncology in October 2025.

“There is limited information about how breast cancer treatments can affect the development of cardiovascular disease,” said study co-senior author Reina Haque, PhD, MPH, a cancer epidemiologist with the Kaiser Permanente Southern California Department of Research & Evaluation. “With this new model, we hope to identify breast cancer survivors who are most likely to develop heart failure in the years after treatment.”

Their research showed that older age and traditional cardiovascular risk factors are the strongest predictors for heart failure among early-stage breast cancer survivors, even after considering breast cancer treatments.

Breast cancer survivors face heart failure risks

While people who survive early-stage breast cancer have an over 90% 5-year survival, they still face risks of treatment-related heart failure and cardiomyopathy. There had previously been no standard way to identify those who could benefit most from cardiac prevention or monitoring.

To develop the risk prediction model, researchers from the Kaiser Permanente Southern California Department of Research & Evaluation, Georgetown University and others analyzed the health records of nearly 26,000 female members of Kaiser Permanente Southern California.

The women were aged 18 to 79 years and newly diagnosed with invasive local or regional breast cancer between 2008 and 2020. The participants had a median follow-up time period of more than 5 years, with a maximum of 14 years. Researchers categorized the women into low, moderate, and high-risk groups based on the risk score.

Researchers created the model by combining data from comprehensive electronic health records that contained established cardiovascular risk factors, as well as breast cancer-specific details, including tumor stage, chemotherapy type, HER2-targeted therapies, endocrine treatment, and radiation therapy.

They found the risk prediction model was able to prospectively identify those at an elevated risk of developing heart failure and cardiomyopathy over 10 years.

Among the individual factors that the researchers identified as causing the most risk were:

• Age. Women aged 65 to 74 had 3.5 times the risk of developing heart failure or cardiomyopathy versus women younger than 40.
• The risk also was higher among patients with hypertension, a history of stroke or heart attacks, as well as those being treated with anthracyclines, or HER2-targeted therapy without anthracycline chemotherapy.
• Cardiovascular risk factors, including diabetes, smoking, and obesity also contributed significantly to the risk of developing heart failure or cardiomyopathy.

Risk-scoring model can be used by clinicians

“This study provided important insights about the risk for heart failure and cardiomyopathy after treatments for breast cancer,” Dr. Haque said. “Prior studies were very limited and did not include women from diverse backgrounds of all ages.”

She added that “this risk scoring model will be simpler to interpret by clinicians working with breast cancer patients and survivors.”

Researchers aim to share this model with other health care organizations, believing it will help improve outcomes for women who have survived cancer.

Dr. Haque noted that, “For example, if the model shows that patients are at high risk of heart failure or cardiomyopathy, then physicians may consider more frequent cardiac assessments than those breast cancer survivors who are at lower risk.”

Other authors on the study include Michael R. Irwin, MD, and Richard Olmstead, PhD, of University of California, Los Angeles; and Lie Hong Chen, MA, of the Department of Research & Evaluation.