Association of Hypoglossal Nerve Stimulation With Improvements in Long-term, Patient-Reported Outcomes and Comparison With Positive Airway Pressure for Patients With Obstructive Sleep Apnea.

Importance: Hypoglossal nerve stimulation (HNS) and positive airway pressure (PAP) have been shown to improve patient-reported outcomes (PROs) in obstructive sleep apnea (OSA). However, to our knowledge, there are no data that compare change in PROs between HNS and PAP or that indicate whether HNS improves comorbid insomnia or depression in the long term. Objectives: To determine whether HNS is associated with improvements in patient-reported sleepiness, insomnia, and depression in the long term and to compare the respective associations of HNS and PAP with improved PROs. Design, Setting, and Participants: This retrospective cohort study used data from patients treated at the Cleveland Clinic for OSA. Participants received either HNS (referred sample) from November 1, 2015, to September 31, 2018, or PAP (previous cohort) from January 1, 2010, to December 31, 2014, for OSA. Patients were matched 3:1 for PAP:HNS based on age, body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), sex, and apnea hypopnea index (AHI). Data were collected at baseline and at prespecified follow-up points. Data were analyzed from March 26, 2020, to September 9, 2021. Exposures: Treatment with HNS vs PAP. Main Outcomes and Measures: Data collected included AHI and Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), Insomnia Severity Index (ISI), and Patient Health Questionnaire-9 (PHQ-9; depression) scores. Results: Among 85 patients receiving HNS (mean [SD] age, 62.8 [9.5] years; 59 men [69.4%]; 77 White patients [90.6%]; mean [SD] BMI, 28.8 [3.1]), compared with 217 matched patients receiving PAP (mean [SD] age, 62.1 [9.9] years; 157 men [72.4%]; 173 White patients [81.2%]; mean [SD] BMI, 29.5 [3.1]) included in the analysis, significant improvements were seen in PHQ-9 scores for HNS vs PAP (least square means, -4.06 [95% CI, -5.34 to -2.79] vs -2.58 [95% CI, -3.35 to -1.82]; mean difference, -1.48 [95% CI, -2.78 to -0.19]) with comparable improvements in ESS, FOSQ, and ISI scores. Clinically meaningful differences were observed in 42 of 65 HNS group patients (64.6%) vs 118 PAP group patients (54.5%) for ESS scores, 29 of 49 HNS group patients (59.2%) vs 67 of 217 PAP group patients (30.9%) for FOSQ scores, 14 of 48 HNS group patients (29.2%) vs 53 of 217 PAP group patients (24.4%) for PHQ-9 scores, and 23 of 49 HNS group patients (46.9%) vs 79 of 217 PAP group patients (36.4%) for ISI scores. At the 1-year post-HNS assessment, meaningful improvements were seen in 17 of 28 patients (60.7%) for ESS scores, 11 of 20 patients (55.0%) for FOSQ scores, 7 of 23 patients (30.4%) for PHQ-9 scores, and 11 of 25 patients (44.0%) for ISI scores. Conclusions and Relevance: In this cohort study of patients with OSA, sustained improvements in PROs were observed 1 year after HNS and were comparable to those for PAP at 3 months. These findings suggest that HNS is a viable treatment for improving insomnia and depression in patients with OSA.

A controlled trial of CPAP therapy on metabolic control in individuals with impaired glucose tolerance and sleep apnea.

STUDY OBJECTIVES: To address whether treatment of sleep apnea improves glucose tolerance. DESIGN: Randomized, double-blind crossover study. SETTING: Sleep clinic referrals. PATIENTS: 50 subjects with moderate to severe sleep apnea (AHI > 15) and impaired glucose tolerance. INTERVENTIONS: Subjects were randomized to 8 weeks of CPAP or sham CPAP, followed by the alternate therapy after a one-month washout. After each treatment, subjects underwent 2-hour OGTT, polysomnography, actigraphy, and measurements of indices of glucose control. MEASUREMENTS AND RESULTS: The primary outcome was normalization of the mean 2-h OGTT; a secondary outcome was improvement in the Insulin Sensitivity Index (ISI (0,120). Subjects were 42% men, mean age of 54 (10), BMI of 39 (8), and AHI of 44 (27). Baseline fasting glucose was 104 (12), and mean 2-h OGTT was 110 (57) mg/dL. Seven subjects normalized their mean 2-h OGTT after CPAP but not after sham CPAP, while 5 subjects normalized after sham CPAP but not after CPAP. Overall, there was no improvement in ISI (0,120) between CPAP and sham CPAP (3.6%; 95% CI: [-2.2%, 9.7%]; P = 0.22). However, in those subjects with baseline AHI ≥ 30 (n = 25), there was a 13.3% (95% CI: [5.2%, 22.1%]; P < 0.001) improvement in ISI (0,120) and a 28.7% (95%CI: [-46.5%, -10.9%], P = 0.002) reduction in the 2-h insulin level after CPAP compared to sham CPAP. CONCLUSIONS: This study did not show that IGT normalizes after CPAP in subjects with moderate sleep apnea and obesity. However, insulin sensitivity improved in those with AHI ≥ 30, suggesting beneficial metabolic effects of CPAP in severe sleep apnea. Clinical trials information: ClinicalTrials.gov Identifier: NCT01385995.

Sex influences endothelial function in sleep-disordered breathing.

BACKGROUND: The bases for the association between sleep-disordered breathing (SDB) and cardiovascular disease are poorly understood. Endothelial dysfunction, assessed with brachial artery ultrasonography, may predict cardiovascular risk and represent preclinical vascular disease. We determined whether flow-mediated dilation (FMD) and peak blood flow (PBF) increase after cuff occlusion is altered with SDB. METHODS: 193 participants (58% women) in a cohort study were studied with overnight polysomnography and subsequent brachial artery ultrasonography. SDB was quantified using the apnea-hypopnea index (AHI) and indexes of overnight desaturation and arousal frequency. Two-dimensional and Doppler-velocity measurements of the brachial artery were obtained at baseline and after 5 minutes of upper-arm cuff occlusion. FMD and PBF were defined as the percentage changes from baseline in brachial artery diameter and flow, respectively. RESULTS: In the entire sample, the AHI was inversely associated with both FMD (r = -0.30, P < .001) and PBF (r = -0.20, P < .001). However, sex-stratified univariate analyses showed that these relationships were exclusive to women. Specifically, FMD was significantly lower in women with an AHI > or = 15 than in women with lower AHI scores (P < .005), with no relationship between AHI and FMD in men. Additionally, PBF decreased significantly with increasing AHI (r = -0.29, P = .010) in women alone. Statistical modeling, adjusting for body mass index, age, and other covariates, similarly showed that SDB severity significantly influenced FMD and PBF, with significant interactions between sex and AHI, reinforcing that the associations between SDB severity and endothelial function were stronger in women than in men. CONCLUSIONS: Moderate levels of SBD are associated with impaired conduit and resistance endothelial function in women. Women with SDB may be more vulnerable to early SDB-related cardiovascular disease than are men.