0651 Not Quite a Replacement: Impact of Hypoglossal Nerve Stimulator (HNS) Implant on AHI Reduction

Abstract Introduction Hypoglossal nerve stimulation (HNS) is a salvage therapy recommended for patients who are intolerant of continuous positive airway pressure (CPAP). A prior meta-analysis noted 86% reduction in apnea hypopnea index (AHI) with CPAP use. Literature reviews evaluating HNS have reported 68% reduction in AHI in appropriately selected patients. The landmark study evaluating HNS defined treatment success as AHI reduction by 50% and to less than 20/hour. Our study evaluated the impact of HNS therapy in patients using the Sher 15 criteria. Methods A random sub-cohort of patients who underwent HNS implantation at a single institution between 2022 and 2024 was identified from retrospective chart review. Patients were included if age was over 18 years, AHI-4% was 15-100/hour and body mass index (BMI) was 40 kg/m2, in accordance with payer guidelines. In our study, treatment success was defined as an AHI reduction of 50 % or more from baseline with a treatment AHI less than 15/hour. Results 46 patients were identified from chart review for preliminary analysis of which 33 patients (71.7%) with pre and post procedure studies were included in the final statistical analyses. The average age of the included patients was 60.7±9.19 years and 84.5% were male. The average pre-implantation BMI was 32.20±3.67 kg/m2, and average pre-treatment AHI-4% was 31.24±16.15/hour. Overall, the average post-implantation AHI-4% was 17.12±23.91/hour. 18/33 patients (54.55%) met treatment success by Sher 15 criteria. The post-surgical complication rate in our cohort was 18.18% and included swelling, bleeding, hematoma, post-nasal drip or dysarthria post procedure. Conclusion Our study noted treatment success in 54.55% of patients who underwent HNS therapy for treatment of OSA. Notably, 28.3% of patients did not have follow-up sleep testing during the study period after this invasive treatment modality. It is vital that referring clinicians and the patients undergoing HNS are aware of therapy success rates and the steps needed to evaluate success. Further data is needed on whether this threshold for success will lead to clinically meaningful outcomes with HNS such as improvement in snoring, daytime sleepiness, quality of life, bed-partner satisfaction, cardiovascular outcomes and mortality. Support (if any)