Yoga Regulates Stress Hormones and Improves Quality of Life for Women With Breast Cancer Undergoing Radiation Therapy


Key Points

  • Women who practiced yoga had a steeper decline in their cortisol levels across the day compared to women who practiced simple stretching exercises.
  • Women in the yoga and simple stretching groups reported a reduction in fatigue after radiation treatment.
  • Women who practiced yoga during the treatment period reported greater benefits to physical functioning and general health and were were more likely to find life meaning from their cancer experience.

For women with breast cancer undergoing radiation therapy, yoga offers unique benefits beyond fighting fatigue, according to a study by Chandwani et al published in the Journal of Clinical Oncology. While simple stretching activities counteracted fatigue, patients who participated in yoga exercises that incorporated controlled breathing, meditation, and relaxation techniques into their treatment plan experienced improved ability to engage in their daily activities, better general health, and better regulation of cortisol. Women in the yoga group were also better equipped to find meaning in the illness experience, which declined over time for the women in the other two groups.

The study also assessed, for the first time, yoga benefits in cancer patients by comparing their experience with patients in an active control group who integrated simple, generic stretching exercises into their lives.

“Combining mind and body practices that are part of yoga clearly has tremendous potential to help patients manage the psychosocial and physical difficulties associated with treatment and life after cancer, beyond the benefits of simple stretching,” said Lorenzo Cohen, PhD, of The University of Texas MD Anderson Cancer Center, Houston.

Study Details

To conduct the study, 191 women with stage 0 to III breast cancer were randomly assigned to one of three groups: yoga, simple stretching, or no instruction in yoga or stretching. Participants in the yoga and stretching groups attended sessions specifically tailored to breast cancer patients for 1 hour, 3 days a week throughout their 6 weeks of radiation treatment.

Participants were asked to report on their quality of life, including levels of fatigue and depression, their daily functioning, and a measure assessing ability to find meaning in the illness experience. Saliva samples were collected and electrocardiogram tests were administered at baseline, end of treatment, and at 1, 3, and 6 months post-treatment.

Yoga Leads to Improved Quality of Life

Women who practiced yoga had the steepest decline in cortisol levels across the day, indicating that yoga had the ability to help regulate this stress hormone. This is particularly important because higher stress hormone levels throughout the day, known as a blunted circadian cortisol rhythm, have been linked to worse outcomes in breast cancer.

Additionally, after completing radiation treatment, only the women in the yoga and stretching groups reported a reduction in fatigue. At 1, 3 and 6 months after radiation therapy, women who practiced yoga during the treatment period reported greater benefits to physical functioning and general health. They were more likely to find life meaning from their cancer experience than the other groups.

According to Dr. Cohen, research shows that developing a yoga practice also helps patients after completing cancer treatment.

“The transition from active therapy back to everyday life can be very stressful, as patients no longer receive the same level of medical care and attention. Teaching patients a mind-body technique like yoga as a coping skill can make the transition less difficult.”

Dr. Cohen and his team are now conducting a phase III clinical trial in women with breast cancer to further determine the mechanisms of yoga that lead to improvement in physical functioning, quality of life and biologic outcomes during and after radiation treatment. A secondary aim of the trial is to conduct cost efficiency analysis for the hospital, assess health-care usage costs in general, and examine work productivity of patients.

Dr. Cohen is the corresponding author for the Journal of Clinical Oncology article.

The study was supported in part by grants from the National Cancer Institute and philanthropic support for the Integrative Medicine Program, The University of Texas MD Anderson Cancer Center. The study authors reported no potential conflicts of interest.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.