Effect of YOCAS yoga on sleep, fatigue, and quality of life: A URCC CCOP randomized, controlled clinical trial among 410 cancer survivors

Carolyn Vachani, RN, MSN, AOCN
The Abramson Cancer Center of the University of Pennsylvania
Last Modified: June 9, 2010

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Most any person going through cancer diagnosis and treatment will tell you their sleep has been affected. Poor sleep, in turn, leads to worse quality of life (QOL) and difficulty carrying out life’s daily activities. While medications can help a person sleep, many patients are hesitant to take yet another pill and practitioners worry about sleep aids interacting with other medications and unwanted side effects. Yoga has been studied in many different patient groups and is thought to have beneficial effects on physical and emotional health.

This study was a nationwide, randomized, controlled clinical trial examining the efficacy of yoga for improving sleep quality, fatigue and QOL among cancer survivors. Patients were randomized to one of two arms: standard follow up care and monitoring (control arm) or standard follow up care plus the 4-week yoga intervention (yoga arm).

The yoga intervention was based on the UR Yoga for Cancer Survivors (YOCAS) program consisting of pranayama (breathing exercises), 18 gentle Hatha and Restorative yoga asanas (postures) and meditation focusing on mindfulness. Yoga sessions were 75 minutes, twice a week, for 4 weeks (8 total sessions). Hatha and Restrorative types of yoga were chosen because they have been shown to have greatest impact based on previous studies, and they are widely available forms of yoga.
Standardization of yoga intervention was provided through the following mechanisms:

  • Highly-involved URCC CCOP yoga consultant
  • Yoga alliance certified instructors
  • Yoga instructional DVD and instructional manual for instructors

Measurement tools were used to assess sleep quality, fatigue and QOL pre and post the four-week intervention.

410 cancer survivors were randomized to the study groups (204 control group and 206 yoga). In the yoga group, 86% of participants attended at least 5 of the yoga sessions, which is good compliance. After four weeks of twice-weekly sessions, patients in the yoga arm reported greater improvement in sleep quality (22% for the yoga group vs. 12% for the control group), reduced incidence of clinically impaired sleep (31% vs. 16%) and less daytime sleepiness (29 % vs. 5%) compared with the control group. The yoga group had a 29% reduction in sleep medication use, whereas the control group had a 5% increase. The yoga group had significantly better sleep quality, QOL and decreased fatigue.

This study shows some of the possible benefits of yoga for cancer survivors. However, participants were 96% female and 75% were breast cancer survivors, making it difficult to generalize results to other groups. In addition, people receiving chemotherapy were not included in the study and this is a group that frequently reports sleep disturbances. Whether or not the results would be similar in a group receiving chemotherapy would need to be studied. Other issues to address would be the availability and cost of yoga to people with cancer. Despite these flaws, this is the largest study to date examining the impact of yoga on sleep disturbances in cancer survivors. Sleep disturbance is a major side effect of cancer therapy that hinders survivors’ quality of life and treatments for these symptoms is essential. The use of yoga and other lifestyle modifications is an area that is exciting and warrants further investigation.

Patient summary of Effect of YOCAS yoga on sleep, fatigue, and quality of life: A URCC CCOP randomized, controlled clinical trial among 410 cancer survivors.

Form more information, please see Interpreting a Cancer Research Study.