Oral appliance therapy (OAT) is an alternative therapy for obstructive sleep apnea (OSA). It is most often recommended for patients who have mild OSA, or who have moderate-severe OSA and are unwilling or unable to comply with continuous positive airway pressure. We sought to identify the subset of patients most likely to benefit from OAT.
Patients of a sleep disordered breathing dental clinic with nocturnal polysomnography date before OAT initiation and during OAT titration. The main outcome variable was success of OAT (post-treatment AHI<10/hr). Secondary outcome measures included average nocturnal oxygen saturation (SpO2) and subjective symptoms. Independent variables available for analysis included patient demographics (age, sex), body anthropomorphic measurements (body-mass index (BMI), neck circumference, canine classification, facial skeletal classification), sleep characteristics (apnea-hypopnea index, average nocturnal oxygen saturation), and intervention (type of oral appliance, posture change during PSG and overall). Comparisons of patients by treatment success were performed using Student’s t-tests and chi-squared tests.
Twenty-nine patients were identified for analysis, with age 54.7±13.3years, 62.1% male, and BMI 30.1 kg/m2. Most patients (76%) had moderate to severe OSA (AHI>20/hr) at baseline. OAT resulted in total posture change of 6.5±3.1mm, with 66.8±32.7% reduction in AHI (p<0.001), 6.8±7.5% absolute increase in SpO2 (p<0.001), improvement of subjective symptoms of 86%, and overall success of 69.0%. In the bivariate analysis, patients with post-treatment success were no different by age, sex, anthropomorphic measurements, or intervention characteristics compared to patients with post-treatment failure, but had higher average baseline SpO2 (82.4% vs. 76.2%, p=0.061). SpO2 remained significantly different after therapy (89.1% vs. 82.1%, p<0.001).
OAT improves AHI, SpO2, and subjective symptoms in most patients with OSA, regardless of severity. Baseline hypoxia may predict failure of OAT monotherapy.
OAT may be appropriate for treatment of OSA patients without baseline hypoxemia. Further studies are needed to evaluate the role for OAT in adjuvant therapy with CPAP and to determine the degree of baseline oxygen saturation that will predict OAT success.
Vidya Krishnan, None.