(dailyRx News) Nobody walks away from breast cancer scot-free. The best of treatments leave the ladies of breast cancer changed, sometimes for years. Research confirms that fitness levels matter. A lot.
Women whose bodies have been touched by and treated for breast cancer commonly have weaker hearts and lungs (cardiopulmonary function).
And in a vicious cascade, these cardiopulmonary weaknesses can lead to a woman's overall physical weakness, weight gain and other health issues that together can shorten her life.
Researchers at Duke University and elsewhere also learned that poor cardiopulmonary function (fitness level really) is a very accurate predictor of how long a woman with advanced cancer will live.
Here's what happens. Certain chemotherapy weakens the heart's ability to pump oxygen-rich blood cells throughout the body. Muscle cells also stop cooperating.
Patients may also have other effects of therapy, becoming less active and gaining weight, which can also impair cardiopulmonary function.
"We know that exercise tolerance tests, which measure cardiopulmonary function, are among some of the most important indicators of health and longevity in people who do not have cancer; however, relatively little research has been done assessing the clinical importance of these tests in patients with cancer," said Lee Jones, PhD, associate professor at Duke and lead author of the study.
Using stationary bikes as a means of measuring exertion capability, researchers tested 268 women in various stages of breast cancer treatment.
Marked impairment of cardiopulmonary function was recorded, even among women who were years out of treatment.
For women with advanced breast cancer, the fitter they were, the longer they lived - about three years vs. 16 months for women who were not so fit.
Jones said, "Fitness level may be an important biomarker of survival among cancer patients."
He added,"But the beautiful thing about fitness is that we can improve it with exercise training,"
Jones, who has several exercise studies currently under way, believes exercise would be "a good intervention" for people living with cancer at all levels - before and after therapy.
This research was published in reported online in the Journal of Clinical Oncology.