SAN ANTONIO — The days when continuous positive airway pressure was the only arrow in the quiver for physicians targeting obstructive sleep apnea are long gone.
The single most popular session at the meeting—the one whose overflow crowds brought out the fire marshals in full force—was devoted to alternatives to CPAP that have come of age: oral appliances; maxillofacial surgery; and weight loss through diet and exercise, bariatric surgery, or drugs.
Session chair James K. Walsh, Ph.D., set the stage, citing studies showing that typically 50% of patients discontinue CPAP within 1 year. Moreover, the percentage of nights patients use their CPAP drops after a couple of months from 50% to 40% and even 30%. An average of about 3 hours of use per night is the norm in clinical practice.
“The goal is to treat sleep apnea every night throughout the night. I'm not at all trying to suggest this therapy is totally ineffective, but I would term it highly suboptimal,” declared Dr. Walsh, executive director of the sleep medicine and research center at St. Luke's Hospital in St. Louis.
Although CPAP remains the guideline-recommended standard therapy for apnea, many patients dislike sleeping while wearing a mask, and often their sleep partners aren't crazy about the CPAP devices, either. Speakers at the session addressed the best-established alternatives.
Oral Appliances
This field has experienced phenomenal growth in recent years as a consequence of American Academy of Sleep Medicine guidelines declaring the devices are indicated for mild to moderate obstructive sleep apnea (OSA).
“For physicians, this is a particularly confusing field. There are more than 100 oral appliances on the market, and I've seen another 4 new ones introduced at this meeting. There's a lot of heavy marketing going on,” said Dr. Alan A. Lowe, professor of oral health sciences and chair of the division of orthodontics at the University of British Columbia, Vancouver.
Not all of the devices have been approved by the Food and Drug Administration, and only seven are backed by clinical trials data. No single device is right for all patients. But as a general rule, the best results are achieved with devices that are adjustable in all planes in space, he stressed.
“The titration of an oral appliance is essential, and it takes weeks to months,” Dr. Lowe said. “You don't just send patients home with a 'boil and bite' device and say, 'Okay, off you go.' You need to go through the titration phase. So physicians who are prescribing oral appliances and just giving them to their patients might as well give them CPAP with a pressure of 7 mm Hg and send them home and tell them to wear it. It's absolutely useless to do that.”
Oral appliances that have been subjected to formal trials typically show roughly an 80% success rate in patients with a baseline apnea-hypopnea index (AHI) below 30 episodes per hour, with the success rate dropping off to 60% in those with more severe OSA. Responders experience less daytime sleepiness, improved cognition, better results on simulated driving performance tests, and reductions in nighttime blood pressure and serum lipids.
When Dr. Lowe and coinvestigators gave patients who were adherent to CPAP a trial period on an oral appliance, 55% subsequently switched over, while 30% maintained a clear preference for CPAP.
“Oxygenation improvement is always greater with CPAP because it forces air into the lungs. Oral appliances simply make the tube bigger and take away the obstruction,” he explained.
Device titration needs to be done by a skilled dentist. The American Academy of Dental Sleep Medicine (
The main side effect associated with oral appliances is that they cause subtle tooth movement. In a series of 70 patients with full polysomnograms and dental records, Dr. Lowe found that only 10 had no change in dentition over time. Of the other 60 patients, 29 had favorable changes in the fit and function of their teeth, whereas 31 had unfavorable changes.
“The issue is how we manage it. I have yet to stop a patient from wearing an oral appliance because of tooth movement that we couldn't manage somehow. It's not an issue of having to cease wear. When we weigh tooth movement against adequate oxygen to the heart, tooth movement loses. I'm trying to train the profession to think that way—panic less about tooth movement and think more about what the treatment is doing for the sleep-disordered breathing,” Dr. Lowe continued.
Besides, his 3-year study of patients using classic CPAP masks showed that they, too, cause quantifiable changes in tooth position over time, he added.