Assessment of the cardiorespiratory fitness and the quality of life of patients with breast cancer undergoing chemotherapy: a prospective study.

Background: Diminished cardiorespiratory fitness is a well-known side effect of chemotherapy as well as a risk factor for potential cardiovascular diseases among cancer patients. This study aimed to assess the potential effects of systemic adjuvant (ACT) or neoadjuvant (NACT) chemotherapy on cardiorespiratory fitness and quality of life (QoL) among breast cancer (BC) patients.

Methods: Demographic data, cardiorespiratory fitness, health-related QoL domains were assessed with simple data form, six-minute walk test (6MWT), European Organization for Research and Treatment of Cancer quality of life module (EORTC-C30), and Functional Assessment of Cancer Therapy (FACT-B+), respectively. Time1 (T1, prior to chemotherapy), Time2 (T2; interim assessment), and Time3 (T3, final assessment) were set as assessment points.

Results: A total of 42 patients (32 ACT vs 10 ACT) completed all assessments. There were no significant differences of main effect of time and time*group interaction on total walked distance (TWD) after controlling for age and BMI (F(2,28) = 1.309, p = 0.286; F(2,28) = 1.444, p = 0.253). EORTC symptoms subscale was found to be correlated with EORTC and FACT-B+ physical function (PF) subscales (r = - 861, p < 0.001; r = - 0.877, p < 0.001) in T3. The EORTC PF subscale was found to be correlated with the TWD in the baseline (r = 0.411, p = 0.024).

Conclusions: This study showed that the effect of chemotherapy on diminished PF and remarkably increased symptom burden among BC patients. Yet, the type of chemotherapy had no effect on TWD regarding cardiorespiratory fitness. Monitoring potential functional decline regarding cardiorespiratory fitness can be performed via simple field tests such as 6MWT.