Efficacy of EPAP enhanced Oral Appliance Therapy in patients with Severe obstructive sleep apnea (OSA) EPAP enhanced Oral Appliance Therapy

<bold>Introduction:</bold> Oral Appliances (OA) are a primary therapy for mild to moderate OSA patients and for CPAP intolerant severe OSA patients. A novel oral appliance, O2Vent Optima incorporates both the mandibular advancement and an air channel that circumvents nasopharyngeal obstruction. The ExVent provides oral Expiratory Positive Airway Pressure (EPAP). Previous studies have established efficacy of the combination therapy in patients with mild and moderate OSA. Our study assessed the efficacy of O2Vent Optima + ExVent for severe OSA patients who were either intolerant or declined CPAP. <bold>Materials and Methods:</bold> A multi-centre prospective, open-label study included 24 severe OSA patients (AHI>30/hr.) who declined CPAP. Average age: 54.6±5.8 years; mean BMI: 32.6±4.3; 70% were men. OA adjustment was clinically guided and optimized, highest resistance EPAP valves (7 cmH2O) were utilized. The participants used the combination therapy >80% of the nights for >12-week period. Efficacy Measures: Change in AHI between baseline vs. treatment in lab PSG. Treatment success (% of patients with ≥50% decrease in AHI from baseline). Improvement in SpO2 nadir. <bold>Results:</bold> Treatment with O2Vent Optima + ExVent reduced AHI from 37.4±10.13/hr. to 11.3±3.56/hr. (p< 0.005), average 71% reduction in AHI. The SpO2 nadir increased from 82.9±6.2% to 89.6±2.1% (p< 0.005). Treatment success rate was 84%. <bold>Conclusions:</bold> There is limited data for oral appliance therapy in patients with severe obstructive sleep apnea who are either CPAP intolerant or decline therapy. Our study demonstrated successful treatment of patients with severe obstructive sleep apnea with O2Vent Optima + ExVent.