The New England Journal of Medicine recently reported on a study conducted in Australia to determine what effect, if any, CPAP therapy would have on cardiovascular events among sleep apnea patients. The study suggests that CPAP provides no benefits for cardiology patients suffering from sleep apnea. Dr. Lee Surkin, a cardiologist and sleep medicine specialist, discusses the study and what it means in this report.
Dr. Surkin explains that the SAVE (Sleep Apnea Cardiovascular Endpoints) trial studied about 2,700 patients centered around Australia and the Asian continent. The subjects were people with moderate to severe sleep apnea and cardiovascular disease. The stand treatment for sleep apnea is CPAP (continuous positive airway pressure). The study’s aim was to see if CPAP therapy had a positive effect on the cardiovascular system of the sleep apnea patients. About half the patients were on CPAP; the other half were not. The study followed the subjects for about four years. The study’s conclusion was that there was no cardiovascular benefit to adding CPAP to a population of patients with moderate to severe sleep apnea.
The study is important, says Dr. Surkin, because it has long been known in the medical world that, over time, sleep apnea can have an adverse effect on the cardiovascular system. It can “[increase] the risk of heart attack, stroke, heart failure, and heart rhythm disturbances.” What has not been known is whether CPAP therapy for sleep apnea can have a positive impact on cardiovascular problems.
Dr. Surkin notes that there have been studies in the past showing some benefit from the use of CPAP therapy. He points out that the SAVE trial data are from patients who got “a sub-therapeutic dose of CPAP.” The average time that patients in the SAVE trial were on CPAP was 3.3 hours. Considering that a night’s sleep is about seven hours, the patients in this study were only treated for half the night. Even more troublesome is that the CPAP was given during the first half of the subjects’ sleep. Dr. Surkin points out that the second half of the night is when most deep sleep occurs. It is a major concern about the validity of the study that the patients involved were not treated long enough each night.
As to treatment for sleep apnea, guidelines indicate that CPAP should be the first treatment option. And CPAP should be used throughout the night’s sleep. Other treatment options include a dental oral appliance (a mandibular advancement device) created by a board certified dental physician. The device holds the jaw in an advanced position that keeps the airway open during sleep. Another option would be an implanted device that delivers stimulation to nerves in the tongue to keep the tongue forward. There is also Provent, a device placed on the nostrils at bedtime. It develops air pressure that keeps the airway open during sleep. For the long term, sleep apnea patients should work on losing weight.
Dr. Lee Surkin, MD, FACC, FCCP, FASNC is a cardiologist in Greenville, North Carolina and is affiliated with multiple hospitals in the area, including Martin General Hospital and Vidant Medical Center. He received his medical degree from Drexel University College of Medicine and has been in practice for more than 20 years. He is board certified in Cardiology, Nuclear Cardiology and Sleep Medicine. He is the founder of the American Academy of Cardiovascular Sleep Medicine. The Health and Wellness Network is a featured network of Sequence Media Group.