Oral Appliance Treatment Demonstrates Similar Improvements in Clinical Outcomes and Better Patient Adherence Compared to CPAP in Patients with Moderate to Severe Obstructive Sleep Apnea

Resident Focus - Volume 8, Issue 49

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Reference: Am J Respir Crit Care Med. 2013 Apr 15;187(8):879-87, (level 2 [mid-level] evidence)

Continuous positive airway pressure (CPAP) is the most commonly implemented treatment for obstructive sleep apnea (OSA). However, many patients with OSA oppose CPAP or incompletely tolerate this modality, hence adversely impacting its effectiveness. Oral appliances, specifically mandibular advancement devices (MAD), are recently introduced modalities used for treatment of mild to moderate OSA. Despite inferior sleep-disordered breathing outcomes with MAD compared to CPAP, compliance with MAD is superior. When considering efficacy and compliance, the OSA clinical outcomes for MAD and CPAP are similar. However, there has been scant evidence regarding use of MAD for more severe cases of OSA. Can mandibular advancement devices be used to effectively treat moderate to severe obstructive sleep apnea?

In this randomized crossover open label study in Sydney, Australia, 126 patients who met eligibility criteria (newly diagnosed OSA, 20 years or older with 2 or more symptoms of OSA ) were randomly assigned to a treatment sequence including both CPAP and MAD with a two-week washout period between treatments in order to compare effects of 1 month optimal treatment. All patients in the study were acclimatized to both devices prior to the initiation of the treatment arms. Most patients had moderate to severe OSA (82%). Full polysomnography determined treatment efficacy. Device use during the night was under patient control. The primary outcome was 24-hr mean arterial pressure (MAP) using ambulatory BP monitoring. Secondary outcomes included neurobehavioral function and quality of life using the Functional Outcomes of Sleep Questionnaire (FOSQ), the Short Form-36 (SF-36), the Epworth Sleepiness Score (ESS), and the AusEd driving simulator. 108 patients (86%) completed the trial of both devices and were included in the analysis.

For the comparison of CPAP and MAD, the primary outcome of 24-hr MAP had a non-significant difference of 0.2 mmHg (95% CI -0.7 to 1.1). The apnea-hypopnea index (AHI) showed a significantly better reduction of 4.5 with CPAP compared to 11.1 with MAD (p=0.0001). When both treatments were compared to baseline, most neurobehavioral outcomes demonstrated improvement. However, there was no significant difference for subjective sleepiness as measured by the ESS or disease-specific quality of life when CPAP was compared to MAD. MAD showed a significant improvement in the SF-36 components of bodily pain, vitality, social function and mental health compared to CPAP (all p<0.05). Driver simulation performance improved to the same extent for both CPAP and MAD. The mean subject-reported compliance rate was 6.5 hrs/night for MAD compared to 5.2 hrs/night for CPAP (p<0.0001). Despite the fact that CPAP was significantly better at decreasing AHI, the MAD devices performed similarly or better on patient oriented outcomes.

This short-term randomized crossover study displayed similar health outcomes for MAD and CPAP in patients with moderate to severe OSA, most likely due to increased compliance in patients using the MAD. Current American Academy of Sleep Medicine practice parameters cite MAD as being a treatment option only in mild to moderate OSA or in those who have failed or declined CPAP treatment. This study challenges that recommendation. MAD should be considered in any OSA patient when there is concern of compliance in CPAP therapy. Additional long-term comparative effectiveness studies of CPAP and MAD are necessary.

Reference: Phillips, C, Grunstein R, Darendeliler M, Mihailidou A, Srinivasan V, Yee B, Marks G, Cistulli P. Health Outcomes of Continuous Positive Airway Pressure versus Oral Appliance Treatment for Obstructive Sleep Apnea. Am J Respir Crit Care Med. 2013 Apr 15;187(8):879-87

For more information, see Obstructive sleep apnea (OSA) in DynaMed.