Cardio Performance Levels May Affect Breast Cancer Survival

After completing treatment, women with breast cancer have considerably impaired cardiopulmonary function that can endure for years, according to a study led by scientists at Duke University Medical Center. Study findings also provide initial indication that poor cardiopulmonary function may be a viable predictor of survival among women with advanced breast cancer. The results were reported online in the Journal of Clinical Oncology.

Lee Jones, PhD, associate professor at Duke and lead author of the study says, “Our work provides initial insights into the effects a cancer diagnosis and subsequent therapy may have on how the heart, lungs and rest of the body work together during exercise.”

To begin understanding the direct and indirect effects of therapy on breast cancer patients, Jones and colleagues examined cardiopulmonary function in 248 women at various stages of treatment for breast cancer. All patients completed a cardiopulmonary exercise test on a stationary bike. During the test, a VO2-peak measurement was obtained.

When compared with healthy women of the same age who were sedentary, researchers found that women with breast cancer, regardless of treatment status, had significantly worse cardiopulmonary function. Those patients who had completed cancer therapy years previously still presented with markedly impaired cardiopulmonary function levels. This suggests that fitness levels may not recover even after therapy. More remarkable was the finding that approximately one-third of women in the study had a cardiopulmonary function score below the threshold that suggests people can function independently.

Furthermore, among the patients with advanced breast cancer, median survival was 36 months in high-fitness patients compared to 16 months in the low-fitness patients.

According to Jones, the findings of this study suggest that exercise may be a healthy intervention for cancer patients both during and after therapy. “Fitness level may be an important biomarker of survival among cancer patients,” he said. “Although we currently do not know if improving fitness in cancer patients is associated with longer survival, our data provide initial evidence to pursue this question.”

Source: Duke University Medical Center.