Cancer patients are three to five times more likely than healthy people to suffer from insomnia and sleep disruptions. According to a study published in the Journal of Clinical Sleep Medicine (2008; 4 , 403–405), breathing rates, heart rates and cortisol levels can help predict whether women with breast cancer will experience sleep issues.
Researchers from University of Rochester Medical Center in New York, Stanford University in California and the University of Griefswald in Griefswald, Germany, participated in the study, which recruited 99 women with metastatic breast cancer.
Scientists discovered that subjects who had lower heart rate variability during a stress task and lower cortisol levels slept more and enjoyed better-quality sleep than others in the trial.
Changes in heart rate are regulated by the parasympathetic nervous system. “We were able to identify the role that [this] system plays in insomnia,” lead study author Oxana Palesh, PhD, research assistant at Rochester’s James P. Wilmot Cancer Center, told Newswise. Palesh added, “It’s reasonable to suggest that simple breathing exercises may help more than we realize with insomnia.”
Palesh recommended using deep diaphragmatic breathing exercises—such as those taught in yoga or meditation—to thwart insomnia and sleep disruptions.