Exercise can improve heart function in women with breast cancer

A recent study reported that exercise benefits women who are undergoing breast cancer treatment. The study was presented on December 7, 2018 at the San Antonio Breast Cancer Symposium, and it was the largest trial to date that measured cardiovascular function in patients before any breast cancer treatment.

According to C. Kent Osborne – co-director of the San Antonio Breast Cancer Symposium and director of Dan L. Duncan Comprehensive Cancer Center at Baylor College of Medicine in Houston – it is the first study to measure maximum oxygen uptake, which is the maximal rate at which oxygen can be used by the body during maximal work.

Maximum oxygen uptake is directly related to the maximal capacity of the heart to deliver blood to the muscles.

Other studies have also examined the benefits of exercise during treatment and confirmed that it is helpful.

Statistics for breast cancer in women in the U.S.

Breast cancer is the most commonly diagnosed cancer among American women. About one in eight women in the U.S. (about 12 percent) is estimated to develop invasive breast cancer over the course of her lifetime. Breast cancer death rates are also higher than rates for any other cancer, except lung cancer. (Related: Breast Cancer Linked to Obesity in Women of All Ages, Leptin Probable Culprit.)

However, being diagnosed with breast cancer isn’t the end of everything.

Today, women who are diagnosed with breast cancer have better outlooks than patients did several years ago. Breast cancer treatments have improved over the years, and survival rates are now higher than they were in the past decade.

According to the American Cancer Society, the five-year relative survival rate of women with breast cancer of all stages is about 90 percent – meaning that, on average, they are about 90 percent as likely to live for at least five years after their diagnosis as women who don’t have the disease.

How exercise improves heart function

Last year, researchers reported that women who participated in a supervised exercise program while undergoing breast cancer treatment had better cardiovascular fitness than women who did not.

The study was sponsored by Oslo University Hospital, St. Olavs Hospital, and The Research Council of Norway. It began in September of 2014 and was conducted by a team of Norwegian researchers.

Their findings are particularly important as breast cancer survivors experience a decrease in heart function after undergoing cancer treatments.

Cancer treatments like chemotherapy and radiation therapy can be harsh, and they can cause toxicity to the heart muscle. The lead author of the study, Inger Thune, also said that cardiovascular disease is a significant cause of death among breast cancer survivors.

The study involved 375 women who had undergone surgery for stage 1 or stage 2 breast cancer. About 57 percent had chemotherapy, while 78 percent had radiation therapy.

The researchers measured the patients’ heart function prior to surgery. Then, they divided the women into two groups: The control group, which did not participate in a supervised exercise program, and the intervention group, which received the benefit of having a trained instructor supervise their twice-weekly, 60-minute workouts.

Their exercise regimen consisted of aerobic exercise, stretching, and weight training. The participants also did additional physical activity on their own for 120 minutes each week.

The researchers reported that women in both the control and intervention groups experienced a decline in their maximum oxygen uptake six months after their surgeries. However, by the 12th month, the women who regularly exercised showed an improvement in their maximum oxygen uptake, while the women in the control group had worsened maximum oxygen uptake.

A full year after their surgeries, the researchers reported that the women in the intervention group had returned to their pre-surgery cardiovascular strength, suggesting that regular exercise strengthened their heart muscles and restored their hearts’ normal function.

“Breast cancer patients should be offered a tailored exercise program that’s based on their pre-surgery level of physical function,” suggested Thune. He also confirmed that the exercise regimen they used for the study was safe.

Sources include:

EverydayHealth.com

Support.Polar.com

BreastCancer.org

Cancer.org

ClinicalTrials.org