For treatment of obstructive sleep apnea (OSA), continuous positive airway pressure, commonly known as CPAP, is the standard treatment. The CPAP, an air pressure device with a mask worn during sleep, is very (99%) effective at maintaining airflow and reducing or eliminating the interrupted breathing that is caused by sleep apnea. In people with OSA, these episodic pauses in breathing—called apneas and hypopneas—cause disruptions to sleep and lower oxygen levels in the bloodstream. Sleep apnea is associated with a number of cardiovascular problems, including high blood pressure, stroke, atrial fibrillation, and congestive heart failure. OSA is also linked to type 2 diabetes and other metabolic disorders.
The biggest challenge to CPAP’s success in treating sleep apnea has been compliance with treatment - wearing the mask. Patients are often uncomfortable using the device, especially at the beginning of treatment, and this reluctance can lead to inconsistent use, or abandonment of the therapy altogether.
New research indicates that some OSA patients may have another treatment option. Researchers at The Netherlands’ University of Groningen compared treatment outcomes for OSA patients using CPAP and oral appliance therapy. They found oral appliance therapy to be an effective alternative to CPAP for treating sleep apnea. Oral appliance therapy involves a dental device similar to a retainer or a mouth guard. Worn during sleep, this device works to keep the airway open, helping to prevent the collapse of the tongue and other muscles at the back of the throat that restrict breathing.
Researchers conducted a 2-year follow up to a clinical trial that compared the effectiveness of CPAP and oral appliance therapy. During the two-year study period, researchers assessed the treatment progress of 103 patients with OSA. They used several standard measurements to track patients’ progress in treatment, including polysomnography and a self-reported sleepiness scale. The severity of OSA is categorized by the frequency of episodes of interrupted breathing, as ranked on a scale known as the apnea-hypopnea index (AHI). For the purpose of this study, researchers defined “successful” treatment as a reduction of AHI to less than 5 episodes per hour, or a reduction of at least 50% from subjects’ initial AHI readings. Their analysis found that oral appliance therapy is an effective alternative to CPAP for some sleep apnea patients:
- For subjects with OSA ranging from mild to severe, researchers found similar levels of success in both CPAP and oral appliance therapy.
- Both oral appliance therapy and CPAP resulted in significant improvements to patients sleep quality, as well as to their levels of daytime sleepiness. Both treatments also showed similar reductions to levels of depression and anxiety, conditions frequently reported by sleep apnea patients.
- Both treatments were effective in reducing frequency of interrupted breathing episodes—but CPAP was found more effective than oral appliance therapy at lowering AHI. CPAP also demonstrated greater effectiveness in raising blood oxygen levels than oral appliance therapy.
Researchers concluded that oral appliance therapy was a viable treatment option for patients with mild to moderate sleep apnea. For severe cases of OSA, researchers recommend CPAP as they best treatment option. Other studies have also found oral appliance therapy works effectively to improve sleep apnea:
- Australian researchers compared the two treatment options among 126 subjects with moderate to severe sleep apnea. After 1 month of observed treatment, they found similar levels of effectiveness in both CPAP and oral appliance therapy. Both treatments showed similar capacity to improve daytime sleepiness and performance. CPAP was shown to be more effective in lowering AHI, while people complied more readily with treatment protocol for oral appliance therapy.
- Another comparison of both treatments found oral appliance and CPAP similarly effective. Researchers observed that both treatments decreased AHI, improved daytime sleepiness and function. As with other studies, CPAP was determined more effective at reducing AHI, and oral appliance had higher rates of compliance.
Compliance has long been an issue with CPAP therapy. Intermittent and inconsistent use of the device undermines its effectiveness. To receive the full benefits of CPAP therapy, it must be used consistently—and for many patients, that has proved difficult. Still, there’s little question that when used correctly and consistently, CPAP can be tremendously effective in treating obstructive sleep apnea, especially severe cases. For people with severe OSA, CPAP will likely remain the standard treatment.
But broadening treatment options for less severe sleep apnea is very good news. People with mild and moderate OSA—especially those who have difficulty with CPAP—may consider speaking with their physician about using oral appliance therapy to manage their condition.
What’s most important is finding the right treatment and sticking with it. Sleep apnea is a serious health condition. Fortunately, treatments used correctly—whether CPAP or oral appliance—can significantly improve your sleep and your general health.
Michael J. Breus, PhD
The Sleep Doctor®