CPAP vs Mandibular Advancement Splint

Family Practice News
March 01, 2013
By: Dr. Jon O. Ebbert MD

Most likely I am not alone with the feeling that we spend a lot of resources diagnosing sleep apnoea, meticulously titrating CPAP devices, and patiently listening to some of our patients as they list the reasons for not using it. Many times, the patients have been back to the sleep specialists, who try in earnest to make it work because we all know the litany of potential adverse downstream effects if apnoea is left untreated. We all also know that frightening our patients (“untreated sleep apnoea can increase the risk for sudden cardiac death and heart failure. …”) into CPAP compliance is ineffective. So, for the lucky patients whose insurance coverage facilitates the fitting of oral appliances, such as the Mandibular Advancement Splint device (MAD), we can try these.

Although the reduction in overall apnoeic episodes is less with MAD than with CPAP devices, the adherence to the MAD may be higher.

So how do CPAP and oral appliances fare head-to-head?
Australian investigators conducted a randomized controlled clinical trial evaluating the health outcomes of patients using the Mandibular Advancement Device (MAD) or CPAP for obstructive sleep apnoea. (Am. J. Respir. Crit. Care Med. Feb. 14, 2013[doi:101164/rccm.201212-2223OC]).

In this study, 126 patients with moderate to severe Obstructive Sleep Apnoea (OSA) were randomly assigned to use the MAD or CPAP for 1 month. Patients were excluded if they had central sleep apnoea, need for immediate treatment, a coexisting sleep disorder, regular use of sedatives or narcotics, or pre-existing lung or psychiatric disease.

The primary outcome was a difference in 24-hour mean arterial blood pressure. Secondary outcomes included cardiovascular events and arterial stiffness. Neurobehavioral function and quality of life also were measured.

CPAP was significantly more effective that MAD for reducing the apnoea-hypopnoea index (AHI), but compliance (continued willingness to wear) was significantly greater with MAD (6.5 hours per night vs. 5.2 hours per night). No differences in the 24-hour mean arterial pressure were observed, though neither treatment improved blood pressure. Sleepiness, driving stimulator performance, and disease-specific quality of life improved with both treatments by similar amounts. MAD was superior to CPAP on several quality-of-life domains.

This study is extremely informative for our practices in which we cannot consistently provide either motivational enhancement or interventions to improve adherence with CPAP. For CPAP-nonadherent patients for whom an appliance seems like an appropriate next step, this should be pursued. In the case of sleep apnoea, we should not let perfect be the enemy of good.

Dr Ebbert is professor of medicine and primary care clinician at the Mayo Clinic in Rochester, Minn. He reports having no conflicts of interest. The opinions expressed are those of the author.