The Effect Of Exercise 24-hours Before Chemotherapy On Cardiac Function And Symptoms In Breast Cancer

Abstract

Rodent studies have demonstrated that a single submaximal exercise bout can attenuate markers of cardiac damage caused by adriamycin chemotherapy injection 24 hr later. However, it is unclear whether this finding extends to humans. PURPOSE: To determine the effects of exercise 24 hr prior to the first chemotherapy treatment on cardiac function in breast cancer patients (BCP). METHODS: Patients were randomized to either: 1) no vigorous exercise for 72 hr prior to first treatment (n = 8), or 2) no vigorous exercise for 48 hrs, then 30 min of vigorous exercise (70% age-predicted heart rate reserve) 24 hr prior to first treatment (n = 9). Chemotherapy treatment included 60 mg/m2 adriamycin and 600 mg/m2 cyclophosphamide. Two-dimensional echocardiography and blood pressure were assessed pre- and 24-48 hr post-treatment. Key cardiac measures included speckle tracking-derived global longitudinal strain (GLS) and standard volumetric measures (e.g., end-diastolic volume (EDV)). Rotterdam Symptom Checklists were administered prior to the first and second treatments. Standardized physical and psychological distress scores were tabulated. Analysis included mixed methods ANOVA with p≤0.05. RESULTS: There were no significant interactions or group differences for GLS, EDV, systolic blood pressure, or resting heart rate. There were significant (p≤0.05) main effects for time (pre vs. post treatment) for GLS (-19.3 ± 1.5 to -21.2 ± 1.8 %), systolic blood pressure (107 ± 14 to 102 ± 14 mmHg) and a trend for EDV (80 ± 13 to 88 ± 16 mL, p=0.06). There was no significant change in heart rate (70 ± 10 to 68 ± 11 bpm). Physical distress increased post-treatment (14 ± 8 to 26 ± 11, p<0.01), while there was a trend toward a decrease in psychological distress (26 ± 13 to 18 ± 17, p=0.07). CONCLUSIONS: Within this initial small sample of BCP, there does not seem to be an effect of aerobic exercise 24 hr prior to receipt of the first adriamyacin chemotherapy treatment on the cardiac function parameters or symptoms measured. The acute effect of chemotherapy is an increase in GLS; and the trend in EDV may be suggestive of an increase in blood volume, but this requires further investigation. Receipt of the first treatment significantly increases physical symptoms, but may decrease the psychological distress associated with anticipation of the first treatment.