Breast cancer treatments can take a heavy toll on lung and heart health and could shorten a woman's life, according to a new study.
Researchers found that breast cancer survivors, even those who had completed their cancer therapy years previously, were less fit than sedentary but healthy women of the same age. One third of breast cancer patients scored so low on a fitness test they might not be able to perform normal tasks, such as walking half a mile or up stairs, the researchers said.
But the study also showed that breast cancer patients who maintained high cardiopulmonary fitness survived 36 months on average, compared with 16 months for patients with low cardiopulmonary fitness.
“The beautiful thing about fitness is that we can improve it with exercise training,” said lead study author Lee Jones, an associate professor at Duke University.
The researchers found an association between cardiopulmonary function and breast cancer treatment, but the study could not suggest that one causes the other. More research is needed to understand the relationship between fitness and breast cancer patients' longevity, particularly because prolonged sitting may raise the risk of breast cancerin the first place, the researchers said.
Breast cancertreatment has improved in recent years, and deaths from the disease have dropped 2.2 percent per year since 1990, the researchers said. But treatment often results in weight gain and lack of energy, which compromises patients' fitness. And chemotherapy can harm the heart’s ability to pump efficiently, while also impairing the function of red blood cells.
The study involved 248 breast cancer patients. The researchers measured participants’ cardiopulmonary function on an exercise bike when they were at rest and when they were pushed to maximum exertion.
Participants were in varied stages of cancer treatment, with some having finished treatment years ago. Researchers compared the patients' fitness levels with those of women without breast cancer who exercised at varying amounts.
This findings suggest that fitness levels may not recover after breast cancer treatments, the researchers said.
The study was published today (May 23) in the Journal of Clinical Oncology.
Pass it on: Treatment for breast cancer may compromise heart and lung health, potentially leading to earlier death, which would make exercise an important part of recovery.