Older patients with breast cancer who exercised before diagnosis may be at a lower risk for cardiovascular disease compared to those who did not, according to a study in JACC: CardioOncology.
Researchers examined 4,015 patients with a confirmed diagnosis of primary breast cancer enrolled in the Women’s Health Initiative, which included postmenopausal women age 50-79. Women with cardiovascular disease, a history of any other malignancy prior to enrollment or a body mass index less than or equal to 18.5kg/m2 were excluded.
In the WHI, exercise history at baseline and follow-up were assessed with a questionnaire where patients reported the frequency, duration and intensity of leisure-time physical activity. Researchers examined exercise data that were collected at the visit closest to breast cancer diagnosis and that was between five years and one month prior to diagnosis.
Metabolic equivalent task values were assigned for levels of physical activity per week and exercise was categorized in quartiles: less than 2.5 MET-hours/week (994 patients); 2.50 to greater than 8.625 (1,008 patients); 8.625 to less than 18 (1,011 patients); and greater than or equal to 18 (1,002 patients).
During the study, 324 cardiovascular events occurred. Researchers found that exercising prior to a breast cancer diagnosis was associated with a 20-37% reduction in the risk of first cardiovascular events. The risk of heart attack and heart failure were not impacted, suggesting that exercise may be associated with a greater risk reduction in other cardiovascular events such as angina, coronary revascularization, peripheral artery disease or stroke. Individuals who met current physical activity recommendations (9 MET-hours/week), prior to diagnosis had a 46% lower risk of coronary heart disease death compared to those who exercised less than recommended.
“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,” lead author Tochi M. Okwuosa, director of the cardio-oncology program at Rush University Medical Center, said in a statement.