March 26, 2003 -- Targeting a common sleep disorder with treatment not only helps people with heart failure sleep better, it can make their hearts healthier. A new study shows that people who suffer from both congestive heart failure and obstructive sleep apnea can benefit from a nighttime therapy designed to treat the sleep disorder known as continuous positive airway pressure, or CPAP.
Researchers say congestive heart failure affects nearly 5 million people in the U.S., and as many as a third of heart failure patients also suffer from obstructive sleep apnea. The sleep disorder causes sufferers to temporarily stop breathing periodically during sleep, which puts extra strain on the heart and can prompt potentially dangerous surges in blood pressure and heart rates.
People with obstructive sleep apnea are more likely that others to suffer from heart failure, but researchers say few studies have looked at whether specifically treating obstructive sleep apnea can relieve some of the symptoms of congestive heart failure.
The study, published in the March 27 issue of TheNew England Journal of Medicine, examined the effects of using CPAP in patients with congestive heart failure and obstructive sleep apnea. CPAP delivers a continuous stream of positive air pressure to the lungs to prevent obstructions and promote normal breathing.
For the study, researcher Yasuyuki Kaneko, MD, of the Sleep Research Laboratories at the Toronto Rehabilitation Institute, and colleagues divided 24 patients diagnosed with congestive heart failure and obstructive sleep apnea into two groups. Both groups received standard medical care for their heart failure, but one also received CPAP at night to treat the sleep disorder.
After a month of treatment, the study found that patients who received the air therapy not only suffered from fewer bouts of obstructive sleep apnea but also showed significant improvement in daytime blood pressure and heart rates. For example, the treated group had a significant increase in pumping ability of the heart -- the usual cause of death and disability in these patients.
Heart rates and blood pressure levels were also significantly lower among the group that received CPAP compared with the non-treated group.
Since obstructive sleep apnea is so prevalent among people with congestive heart failure, researchers say use of CPAP could be an important addition to conventional drug-based therapy for congestive heart failure. The authors say there needs to be a greater awareness among doctors about the role obstructive sleep apnea plays in congestive heart failure, and the sleep disorder should be treated in these patients.
SOURCE: The New England Journal of Medicine, March 27, 2003.