The effects of yoga on mood disturbance and pain in an underserved breast cancer population

Abstract

Breast cancer diagnosis and its treatments are often associated with mood disturbance including anxiety, depression and anger. Pain is also a common problem for breast cancer patients throughout the treatment process. Yoga as a tool for reducing mood disturbance and pain has been demonstrated across a spectrum of medical populations yet has rarely been studied with cancer patients. As part of an ongoing pilot study investigating the effects of yoga on quality of life in breast cancer patients randomized to either a 12-week yoga intervention or wait-list control, this substudy examines yoga's effects on self-reported levels of mood disturbance and pain. The sample consists of ethnically diverse women (46% African American, 30% Hispanic, 24% White) diagnosed within the past year at stages I--II (78%), on chemotherapy (51%) or hormonal treatment (36%), and of an average age of 53 years. Forty seven women comprised the intervention group assigned to weekly yoga classes and 20 women to the control group; with both groups followed for a 3-month period. The following measures were used to assess mood disturbance and pain: the Profile of Mood States, a one-item Functional Assessment of Cancer Therapy pain score, and the Short-form McGill Pain Questionnaire. Sixty three percent of the intervention group attended between 1--19 classes within the 12-week intervention period and 62% report monthly-daily home yoga practice. Based on changes from baseline to three months, between-group analyses indicate that intervention patients experienced a significant reduction (p < .05) in anger-hostility scores as compared to the wait-list control group. A similar marginally pattern emerged for the anxiety-tension and total disturbance scores as compared to the control group. Contrary to prediction, yoga did not have a significant effect on pain severity for either intervention or control group. Results suggest that a yoga intervention in underserved ethnic minority breast cancer patients has implications for improved mood through expression of negative mood states. Further recruitment to attain a larger sample size and a more stable measurement of pain, will help clarify the efficacy of yoga as a behavioral intervention to promote psychological and physical well-being of breast cancer patients undergoing treatment.