A history of regular exercise may provide older breast cancer survivors with greatly needed cardiovascular protection, according to new research.

Breast cancer patients are living longer thanks to advances in care. But these older survivors are at increased risk for age-related disease. In fact, cardiovascular disease is the leading cause of death in individuals with primary breast cancer past age 65. 

But women who exercise prior to their diagnosis may better withstand the damaging effects of cancer treatment, said Tochi Okwuosa, D.O., director of cardio-oncology at Rush University Medical Center, Chicago.

Okwuosa and colleagues examined over 4,000 patients with a diagnosis of primary breast cancer aged 50 to 79 years. Study subjects had no history of cardiovascular disease or prior cancer diagnoses.

The researchers found that people who exercised prior to their breast cancer diagnosis were up to 37% less likely to have a first cardiovascular event. The risk of heart attack and heart failure were not impacted however, suggesting that exercise had an effect on other cardiovascular conditions such as angina, coronary revascularization, peripheral artery disease or stroke.

In addition, individuals who met current physical activity recommendations (9 metabolic equivalent task-hours per week) were 46% less likely to die from coronary heart disease, Okwuosa and colleagues reported. 

The researchers theorized that people who exercise have a higher capacity to tolerate the cardiovascular toxic effects that are sometimes experienced as a side effect of cancer treatment. These patients are also more likely to be more active during cancer treatment, and this behavior is linked to a lower risk of cardiovascular events, Okwuosa said.

“This study is the first to show the exposure to exercise prior to a cancer diagnosis may potentially protect against or mitigate the established adverse cardiovascular consequences observed in breast cancer patients, adding to the growing evidence base supporting the importance of exercise to prevent cardiovascular events in high-risk populations,” Okwuosa concluded.

The results were published in the inaugural issue of JACC: CardioOncology