Effects of an 18-Week Integrated Yoga Program on Cardiac Autonomic Function in Breast Cancer Patients Undergoing Adjuvant Chemotherapy: A Randomized Controlled Trial.

BACKGROUND: Cardiotoxicity is a commonly observed adverse effect seen in breast cancer (BC) patients undergoing chemotherapy with attributes toward cardiac autonomic dysfunction (CAD). Yoga, a mind-body system of medicine that has been shown to improve cardiac autonomic nervous system (ANS) activity in various health conditions, could be an effective adjuvant approach in addressing CAD. OBJECTIVE: This study aims to investigate the protective effects of Integrated Yoga Therapy (IYT) on ANS functioning, assessed using Heart rate variability (HRV) in breast cancer patients undergoing chemotherapy. METHODS: A total of 68 (stage I-III) BC patients were randomly assigned into 2 groups: Treatment as Usual group (TAU) and TAU with Yoga Therapy group (TAUYT). All patients underwent anthracycline-based adjuvant chemotherapy for a total of 6 cycles with 21 days/cycle. During chemotherapy, the TAUYT group received IYT 5 days a week for 18 weeks, compared with usual care alone in the TAU group. Resting heart rate (RHR) and HRV, measured in both the time and frequency domains, were used to assess the cardiac ANS function of each patient before and after 6 cycles of chemotherapy. RESULTS: A total of 30 subjects in the TAU group and 29 subjects in the TAUYT group were included in the analysis. At baseline (before chemotherapy), there were no significant differences between the TAU and TAUYT groups in terms of RHR and HRV indices. However, after chemotherapy, patients in the TAU group had a significantly higher average RHR (P < .02) and lower HRV indices with reduced parasympathetic indices: RMSSD (P < .01), pNN50% (P < .04), high-frequency power (P < .001) and increased sympathetic indices: low-frequency power (P < .001) with sympathovagal imbalance: LF/HF (P < .001) compared with patients in the TAUYT group. CONCLUSION: The study showed the protective effects of yoga therapy on CAD in patients receiving anthracycline-based chemotherapy for BC, proposing yoga as a potential adjuvant intervention in improving cardiac health and preventing cardiovascular-related morbidities. TRIAL REGISTRATION: This trial is registered with the Clinical Trials Registry-India (CTRI) database (CTRI/2020/10/028446; October 16, 2020).

Impact of integrated yoga therapy on cognitive impairment and cardiac dysfunction in relation to quality of life in breast cancer patients undergoing chemotherapy: Study protocol for a two-arm randomized controlled trial.

Background: Chemotherapy-related cognitive impairment (CRCI) and cardiac dysfunction (CRCD) are common adverse effects seen in breast cancer patients undergoing chemotherapy. Even though these effects significantly influence daily functioning and overall quality of life, effective strategies to avoid and/or mitigate these adverse effects remain elusive. Yoga as a Mind-body intervention has been used increasingly by cancer patients and has undergone empirical investigations as a potential intervention for patients with cancer. Furthermore, yoga is associated with improved cognition and cardiac functioning in healthy older adults and subjects with cognitive and cardiac impairments. Accordingly, in the current study, yoga holds promise as an intervention to prevent/manage CRCI and CRCD with improved overall QOL in women receiving chemotherapy for breast cancer. Methods: The study is a two-arm, randomized controlled trial. Women diagnosed with stage I-III breast cancer and awaiting neo-adjuvant or adjuvant chemotherapy will be recruited from a tertiary care center in Bangalore, India. Following recruitment, subjects are randomized to the intervention group (integrated yoga therapy intervention during chemotherapy) or the control group (standard care during chemotherapy). The study's primary outcome is to measure the quality of life (cognitive domain) using European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). The other primary objectives will include cognitive functioning using neuropsychological test battery and cardiac autonomic function testing using heart rate variability. Secondary outcomes are Brain-derived neurotrophic factor (BDNF), brain function (functional MRI), Echocardiography, serum cortisol, Functional assessment of cancer therapy-cognition (FACT-Cog V3), perceived stress scale and Ryff Scales of Psychological Well-Being. Assessments take place before, during and after chemotherapy; 16-weeks post chemotherapy and 1-year post-baseline. Discussion: Yoga is a promising intervention for preventing and/or managing chemotherapy-related adverse effects (CRAE) and enhancing the quality of life among breast cancer patients. The findings from this study may also help understand the inner mechanisms involved in the protective and restorative effects of yoga on CRAE and support the use of yoga prophylactically for breast cancer patients. In addition, the results of this study could help chemotherapy-exposed individuals with other solid cancer types who have cognitive and cardiac issues. Ethics and Dissemination: The study is approved by the ethics committee of the HealthCare Global Enterprises Ltd. Hospital (EC/434/19/01) and National Institute of Mental Health and Neurosciences (NIMH/DO/ETHICS SUB-COMMITTEE (BS&NS) 9th MEETING/2018). Clinical Trial Registration: http://ctri.nic.in/Clinicaltrials/advancesearchmain.php, identifier CTRI/2020/10/028446.