WASHINGTON — Regular exercise before breast cancer diagnosis was associated with reductions in CV risk among women treated for breast cancer, according to a new report presented at the American College of Cardiology Scientific Session.
“Next to a second or recurrent cancer, heart disease is the second leading killer in cancer patients and survivors, so anything we can do to prevent cancer survivors from developing heart disease is very important,” Tochi Okwuosa, DO, CVD specialist at Rush University Medical Center, Chicago, said in a press release. “We found that with exercise, even before one is diagnosed with cancer, you can lower the risk of [CV] problems that are caused by chemotherapy and radiation therapy.”
Researchers analyzed data from 4,015 patients diagnosed with non-metastatic breast cancer. Participants completed questionnaires on their exercise levels within the 5 years prior to cancer diagnosis.
Exercise levels were stratified by the number of metabolic equivalent task (MET) hours: low (< 2.5 MET hours per week; n = 994), intermediate (2.5 to 8.6 MET hours per week; n = 1,008), moderate (8.6 to 18 MET hours per week; n = 1,011) and high (> 18 MET hours per week; n = 1,002).
These levels were compared to the participants’ risk for a CV event after cancer treatment, which included MI, HF, coronary revascularization, angina, carotid artery disease, peripheral artery disease, stroke, transient ischemic attack and CV death.
At follow-up (median, 12.7 years), the risk for CV events (HR = 0.63; 95% CI, 0.43–0.88)
and death from CHD (HR = 0.41; 95% CI, 0.21–0.78) decreased in the group with high exercise compared with those with low exercise levels, according to Okwuosa and colleagues.
Compared with those with low physical activity, those with moderate exercise (HR = 0.86; 95% CI, 0.64-1.17) and intermediate exercise (HR = 0.8; 95% CI, 0.59-1.09) also had lower risk for CV events, the researchers found.
The risk for CHD death was 35% lower in those with intermediate exercise, 54% lower in those with moderate exercise and 59% lower in those with high levels of exercise compared with those with low levels of exercise, according to the researchers.
Compared with those with less than 9 MET hours per week (n = 2,039), those with greater than 9 MET hours per week (n = 1,976) had lower risk for CV death (HR = 0.56; 95% CI, 0.35–0.89) and a trend towards lower risk for CV events (HR = 0.84; 95% CI, 0.67–1.06).
“Exercise provides a level of conditioning within our bodies which, even when we’re under [CV] stress such as with cancer treatments at some later point, helps us tolerate that stress better.” Okwuosa said in the release. “Exercise performed throughout one’s life or even close to the time of cancer diagnosis seems to help the patients down the line with respect to the [CV] problems and side effects of the cancer therapy.”– by Darlene Dobkowski
Palomo A, et al. Abstract 1187-045. Presented at: American College of Cardiology Scientific Session; March 17-19, 2017; Washington, D.C.
Disclosure: Okwuosa reports no relevant financial disclosures.
Editor’s Note: This article was updated on March 21, 2017 to reflect changes in the data.