0621 Cardiovascular Outcomes after Hypoglossal Nerve Stimulation for OSA: Preliminary Results from the MET12 Study

Abstract Introduction Obstructive sleep apnea (OSA) is strongly linked to adverse cardiovascular outcomes including hypertension, hyperlipidemia, arrhythmias, and stroke. Positive airway pressure (PAP) is first-line therapy for moderate-to-severe OSA, but only about 50% of patients are adherent. Hypoglossal nerve stimulation (HNS) is increasingly used for patients intolerant to PAP. We aimed to assess the cardiovascular outcomes after HNS in moderate-to-severe OSA. Methods We conducted a single-center, prospective pre-post study of adults undergoing HNS implantation for OSA. Post-operative testing at 3 months required >20 hours/week HNS use for 30 days. Cardiovascular measures included: 24-hour ambulatory blood pressure (BP), lipid profile, serum catecholamines, and resting heart rate (HR) and HR variability captured by a wearable activity monitor (Fitbit). All patients underwent pre- and post-operative home sleep apnea tests and completed Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and Functional Outcomes of Sleep Questionaire-10 (FOSQ-10). Results To date, twenty-one participants have undergone HNS implantation, with fourteen completing pre- and post-operative testing. Of those participants completing the testing, most identified as male gender (64%) and white race (85%), with mean age 63 years and mean BMI of 31.7 kg/m2. Twelve (86%) participants self-reported hypertension; nine (64%) were prescribed antihypertensive medications; four (29%) specifically were treated with beta-blockers. Seven (50%) participants self-reported hyperlipidemia; six (43%) received statin therapy. On average, the apnea-hypopnea index by 3% criteria (AHI3a) decreased by 36% (38±14.0 pre vs. 26.8±16.5 events/hour post; p < 0.005); four out of 14 participants (28.5%) met Sher criteria (>50% reduction and AHI3a < 20). Daytime sleepiness improved by ~51% (ESS score; 8.7±1.5 pre vs. 4.2±0.5 post; p< 0.005). Postoperative HNS use averaged 7.8 hours/night. Mean 24-hour BP (systolic, diastolic, mean), nocturnal BP dipping, catecholamines, lipid profile, resting HR and HR variability did not significantly differ following HNS therapy. Conclusion Our data to date demonstrates feasibility of characterizing cardiovascular profiles of patients with OSA before and after HNS implantation. Ongoing analyses will provide further clarity and enhance our understanding of these preliminary findings. As the first pilot pre–post study examining cardiovascular outcomes of HNS therapy, this work may help guide future, larger trials. Support (if any) NIH F32HL182221; ATS ASPIRE Fellowship.