Safety and efficacy of upper airway stimulation in treatment of obstructive sleep apnea

Abstract

Introduction Moderate to severe obstructive sleep apnea (OSA) is associated with significant health risks. Continuous positive airway pressure (CPAP) can mitigate these risks, although effectiveness is frequently compromised by inadequate adherence to treatment. We hypothesized that electrical stimulation of the hypoglossal nerve would restore upper airway patency and provide an alternative treatment option for OSA. The primary aim of this study was to determine the safety and efficacy of upper airway stimulation for treatment of OSA. Materials and methods The design was a prospective, multicenter trial with randomized therapy withdrawal arm. The study enrolled participants with moderate to severe OSA who had failed or had not tolerated CPAP. All qualified participants underwent a screening polysomnographic (PSG) study, surgical consultation and drug-induced sleep endoscopy (DISE). Participants without complete concentric collapse at the retropalatal airway received an implanted neurostimulator (Upper Airway Stimulation system, Inspire Medical Systems, Minnesota). All implanted participants were followed for 12months to collect adverse events. Therapy efficacy was evaluated by PSG and quality of life measures Epworth Sleepiness Scale (ESS) and Functional Outcomes of Sleep Questionnaire (FOSQ) at 12months compared with baseline. The therapy withdrawal effect was evaluated by randomizing half of consecutive therapy responders at 12months to oneweek of therapy suspension versus therapy maintenance followed by a PSG. Results 126 participants (21 females) received an implanted system. Average age was 54.5 ± 10.2yrs and BMI was 28.4 ± 2.6kg/m 2 . At 12months, there was a significant reduction in the Apnea Hypopnea Index (AHI) from a median of 29.3 (IQR of 14.9) at baseline to 9.0 (IQR of 18.2) and the Oxygen Desaturation Index from a median of 25.4 (IQR of 17.1) to 7.4 (IQR of 17.0). The ESS and FOSQ also showed significant improvement from pre-implant to 12months. The therapeutic effect of stimulation was also confirmed at 12months with a significant increase in AHI in the therapy withdrawal arm vs. no change in the therapy maintenance arm. Conclusion Upper airway stimulation is effective for the treatment of moderate to severe OSA with clinically and statistically significant improvement in objective and subjective measurements of OSA severity. Acknowledgements Funding source: Inspire Medical Systems, Minnesota; ClinicalTrials.gov number, NCT01161420.