Sleep Quality May Predict Breast Cancer Survival

Sleep quality may predict survival time in women with advanced breast cancer.

New research reveals that higher sleep quality significantly predicted mortality rates over the following six years.

Researchers noted that the findings held true even after adjusting for baseline prognostic factors such as age, estrogen receptor status and treatments.

Study data shows that the average survival was 68.9 months for good sleepers compared with 33.2 months for those who experience poor sleep.

Researchers found that a 10 percent increase in sleep efficiency reduced the estimated risk of death by 32 percent. However, the study found no correlation between sleep time and survival rates.

"We were surprised by the magnitude of the relationship between sleep quality and overall survival even after we accounted for medical and psychological variables that typically predict survival," lead author Oxana Palesh, PhD, assistant professor in the Department of Psychiatry and Behavioral Sciences at Stanford University and research director of the Stanford Cancer Survivorship, said in a news release.  "Good sleep seems to have a strongly protective effect, even with advanced breast cancer."

The latest study involved 97 women with advanced breast cancer who had an average age of 55 years. Sleep quality were measured by wrist actigraphy for three consecutive days.  Researchers found that on average participants spent about eight hours in bed, but slept for only 6.5 hours.

"This study emphasizes the importance of assessing sleep quality among women with breast cancer," noted American Academy of Sleep Medicine President Dr. M. Safwan Badr, according to a statement. "Healthy sleep is critical for physical health, quality of life and overall well-being."

"There are effective treatments for sleep disruption in the general population, and some of them have shown to be effective in cancer survivors as well," said Palesh.  "But much more research is needed to develop and test interventions that are adapted for cancer patients and survivors.  These interventions might not only improve quality of life, but can potentially improve survival."

The findings are published in the journal Sleep.