[Hypoglossal Stimulation: Indication, Surgical Technique and Clinical Results]. / Hypoglossus-Stimulation: Indikation, operative Technik und klinische Ergebnisse.

Hypoglossal stimulation is a safe and effective treatment option for patients with obstructive sleep apnea and unsuccessful PAP therapy. A number of criteria must be met for the indication: proof of failed PAP therapy and ineffectiveness of the other therapy alternatives, AHI of 15-65/h (a relevant number of central and/or mixed apneas should be excluded) and BMI up to max. 35kg/m2. In the case of the respiratory-synchronous and bilateral stimulation system, a complete concentric collapse at the velum level should currently be ruled out in DISE. In the future, stimulation of the branch of the ansa cervicalis innervating the sternothyroid muscle and the ramus internus of the superior laryngeal nerve could open up additional treatment options.

Long-Term Generator Replacement Experience in Hypoglossal Nerve Stimulator Therapy Recipients With CPAP-Intolerant Obstructive Sleep Apnea.

OBJECTIVE: In the last decade, hypoglossal nerve stimulation (HNS) has emerged as a therapeutic alternative for patients with obstructive sleep apnea. The original clinical trial cohorts are entering the phase of expected battery depletion (8-12 years). This study aimed to examine the surgical experience with implantable pulse generator (IPG) replacements and the associated long-term therapy outcomes. STUDY DESIGN: Retrospective analysis of patients from the original clinical trial databases (STAR, German post-market) who were followed in the ongoing ADHERE registry. SETTING: International multicenter HNS registry. METHODS: The ADHERE registry and clinical trial databases were cross-referenced to identify the serial numbers of IPGs that were replaced. Data collection included demographics, apnea-hypopnea index (AHI), therapy use, operative times, and adverse events. RESULTS: Fourteen patients underwent IPG replacement 8.3 ± 1.1 years after their initial implantation. Body mass index was unchanged between the original implant and IPG replacement (29 ± 4 vs 28 ± 2 kg/m2 , p = .50). The mean IPG replacement operative time was shorter than the original implant (63 ± 50 vs 154 ± 58 minutes, p < .002); however, 2 patients required stimulation lead replacement which significantly increased operative time. For patients with available AHI and adherence data, the mean change in AHI from baseline to latest follow-up (8.7 ± 1.1 years after de novo implant) was -50.06%, and the mean therapy use was 7.2 hours/night. CONCLUSION: IPG replacement surgery was associated with low complications and shorter operative time. For patients with available outcomes data, adherence and efficacy remained stable after 9 years of follow-up.

Hypoglossal nerve stimulation for obstructive sleep apnea: updated position paper of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery.

Since the first statement of the German Society of Oto-Rhino-Laryngology, hypoglossal nerve stimulation (HNS) is meanwhile an established treatment option for obstructive sleep apnea (OSA). There are three HNS systems available in Germany which differ in their technical details of the underlying comparable basic principle. For the unilateral HNS with respiratory sensing, several comparative studies, high-volume register analysis and long-term reports exist. The continuous HNS without respiratory sensing does not require a sleep endoscopy for indication. For the bilateral continuous HNS as the single partially implantable device, a feasibility study exists. For indication, the assessment of positive airway pressure failure by sleep medicine is crucial, and the decision for HNS should be made in discussion of other treatment options for at least moderate OSA. The implantation center holds primarily responsibility among the interdisciplinary sleep team and is primary contact for the patient in problems. This depicts why structural processes are required to secure outcome quality and minimize the complications. The aftercare of HNS patients can be provided interdisciplinary and by different medical institutions, whereat, minimal reporting standards to document outcome and usage are recommended.

[Hypoglossal Nerve Stimulation in the Treatment of Obstructive Sleep Apnea]. / Die Hypoglossus-Stimulation zur Therapie der obstruktiven Schlafapnoe.

Reduced genioglossus muscle tone is considered one of the major causes for obstructive sleep apnea (OSA). Hypoglossal nerve stimulation (HNS) keeps the upper airway patent by increasing the muscle tone of the genioglossus muscle being the major airway opener. According to the German S3-Guideline on Sleep Disordered Breathing this treatment is indicated in patients with OSA failing or rejecting positive airway pressure, showing an AHI between 15 and 65, in particular when anatomy is normal and the BMI below 35. In 2021 it has been made available for regular patient care in Germany. However, breathing synchronized, continuous, and bilateral HNS differ in parts relevantly regarding their patient selection criteria, technical features, surgical technique, therapy setting and programming, and daily use for the patient. There are many publications showing the safety, efficacy, and patient satisfaction of breathing synchronized HNS. Less but promising data are available for continuous and the most recent bilateral HNS.

Impact of Body Mass Index and Discomfort on Upper Airway Stimulation: ADHERE Registry 2020 Update.

OBJECTIVES/HYPOTHESIS: To provide the ADHERE registry Upper Airway Stimulation (UAS) outcomes update, including analyses grouped by body mass index (BMI) and therapy discomfort. STUDY DESIGN: Prospective observational study. METHODS: ADHERE captures UAS outcomes including apnea-hypopnea index (AHI), Epworth sleepiness scale (ESS), therapy usage, patient satisfaction, clinician assessment, and safety over a 1-year period. BMI ≤32 kg/m2 (BMI32 ) and 32 < BMI ≤35 kg/m2 (BMI35 ) group outcomes were examined. RESULTS: One thousand eight hundred forty-nine patients enrolled in ADHERE, 1,019 reached final visit, 843 completed the visit. Significant changes in AHI (-20.9, P < .0001) and ESS (- 4.4, P < .0001) were demonstrated. Mean therapy usage was 5.6 ± 2.2 hr/day. Significant therapy use difference was present in patients with reported discomfort versus no discomfort (4.9 ± 2.5 vs. 5.7 ± 2.1 hr/day, P = .01). Patients with discomfort had higher final visit mean AHI versus without discomfort (18.9 ± 18.5 vs. 13.5 ± 13.7 events/hr, P = .01). Changes in AHI and ESS were not significantly different. Serious adverse events reported in 2.3% of patients. Device revision rate was 1.9%. Surgical success was less likely in BMI35 versus BMI32 patients (59.8% vs. 72.2%, P = .02). There was a significant therapy use difference: 5.8 ± 2.0 hr/day in BMI32 versus 5.2 ± 2.2 hr/day in BMI35 (P = .028). CONCLUSIONS: Data from ADHERE demonstrate high efficacy rates for UAS. Although surgical response rate differs between BMI32 and BMI35 patient groups, the AHI and ESS reduction is similar. Discomfort affects therapy adherence and efficacy. Thus, proper therapy settings adjustment to ensure comfort is imperative to improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2616-2624, 2021.

Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions, and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum.

Hypoglossal nerve stimulation (HGNS) has evolved as a novel and effective therapy for patients with moderate-to-severe obstructive sleep apnea. Despite positive published outcomes of HGNS, there exist uncertainties regarding proper patient selection, surgical technique, and the reporting of outcomes and individual factors that impact therapy effectiveness. According to current guidelines, this therapy is indicated for select patients, and recommendations are based on the Stimulation Therapy for Apnea Reduction or STAR trial. Ongoing research and physician experiences continuously improve methods to optimize the therapy. An understanding of the way in which airway anatomy, obstructive sleep apnea phenotypes, individual health status, psychological conditions, and comorbid sleep disorders influence the effectiveness of HGNS is essential to improve outcomes and expand therapy indications. This article presents discussions on current evidence, future directions, and research gaps for HGNS therapy from the 10th International Surgical Sleep Society expert research panel. CITATION: Suurna MV, Jacobowitz O, Chang J, et al. Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum. J Clin Sleep Med. 2021;17(12):2477-2487.

Die Stimulation des Nervus hypoglossus in der Behandlung der obstruktiven Schlafapnoe ­ Aktualisiertes Positionspapier der Arbeitsgemeinschaft Schlafmedizin der DGHNO-KHC.

Hypoglossal nerve stimulation for obstructive sleep apnea - Updated position paper of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. Since the first statement of the German Society of Oto-Rhino-Laryngology, hypoglossal nerve stimulation (HNS) is meanwhile an established treatment option for obstructive sleep apnea (OSA). There are three HNS systems available in Germany which differ in their technical details of the underlying comparable basic principle. For the unilateral HNS with respiratory sensing, several comparative studies, high-volume register analysis and long-term reports exist. The continuous HNS without respiratory sensing does not require a sleep endoscopy for indication. For the bilateral continuous HNS as the single partially implantable device, a feasibility study exists. For indication, the assessment of positive airway pressure failure by sleep medicine is crucial, and the decision for HNS should be made in discussion of other treatment options for at least moderate OSA. The implantation center holds primarily responsibility among the interdisciplinary sleep team and is primary contact for the patient in problems. This depicts why structural processes are required to secure outcome quality and minimize complications. The aftercare of HNS patients can be provided interdisciplinary and by different medical institutions whereat minimal reporting standards to document outcome and usage are recommended.

Results of the ADHERE upper airway stimulation registry and predictors of therapy efficacy.

OBJECTIVE/HYPOTHESIS: The ADHERE Registry is a multicenter prospective observational study following outcomes of upper airway stimulation (UAS) therapy in patients who have failed continuous positive airway pressure therapy for obstructive sleep apnea (OSA). The aim of this registry and purpose of this article were to examine the outcomes of patients receiving UAS for treatment of OSA. STUDY DESIGN: Cohort Study. METHODS: Demographic and sleep study data collection occurred at baseline, implantation visit, post-titration (6 months), and final visit (12 months). Patient and physician reported outcomes were also collected. Post hoc univariate and multivariate analysis was used to identify predictors of therapy response, defined as ≥50% decrease in Apnea-Hypopnea Index (AHI) and AHI ≤20 at the 12-month visit. RESULTS: The registry has enrolled 1,017 patients from October 2016 through February 2019. Thus far, 640 patients have completed their 6-month follow-up and 382 have completed the 12-month follow-up. After 12 months, median AHI was reduced from 32.8 (interquartile range [IQR], 23.6-45.0) to 9.5 (IQR, 4.0-18.5); mean, 35.8 ± 15.4 to 14.2 ± 15.0, P < .0001. Epworth Sleepiness Scale was similarly improved from 11.0 (IQR, 7-16) to 7.0 (IQR, 4-11); mean, 11.4 ± 5.6 to 7.2 ± 4.8, P < .0001. Therapy usage was 5.6 ± 2.1 hours per night after 12 months. In a multivariate model, only female sex and lower baseline body mass index remained as significant predictors of therapy response. CONCLUSIONS: Across a multi-institutional study, UAS therapy continues to show significant improvement in subjective and objective OSA outcomes. This analysis shows that the therapy effect is durable and adherence is high. LEVEL OF EVIDENCE: 2 Laryngoscope, 130:1333-1338, 2020.

Long-term follow-up of the German post-market study for upper airway stimulation for obstructive sleep apnea.

PURPOSE: Upper airway stimulation (UAS) is an effective treatment for obstructive sleep apnea (OSA) in positive airway pressure (PAP) failure. Most reports have presented short-term data, so long-term safety and efficacy reports are rare. The German post-market study (G-PMS) has followed approximately 60 patients from three implanting centers for several years. METHODS: Patients with OSA and PAP failure qualified for the G-PMS by the absence of obesity class 2 an AHI between 15 and 65 events/h and absence of complete concentric collapse at the velum during drug-induced sleep endoscopy. Optional 2- and 3-year follow-ups after implantation were collected during routine clinical practice. We measured respiratory parameters such as apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) and daytime sleepiness using the Epworth sleepiness scale (ESS) in a per protocol analysis. Usage was calculated from device-downloaded reports. Device-related complications were documented. RESULTS: Of the 60 original patients, 41 returned for 2-year follow-up, and 38 for 3 years. About 76% at 2 years and 68% at 3 years met the criterion of therapy success defined as an AHI below 15/h. The median AHI was reduced from 28.6/h (baseline) to 9.0/h (2 years) and 10.0/h (3 years); whereas median ODI decreased from 27.0 to 6.3/h (2 years), and 8.3/h (3 years). Median ESS improved from baseline 13 points to 4 (2 years) and 6 (3 years). Usage was stable at approximately 45 h per week at 2 and 3 years. Serious device-related adverse events were rare, with two-device explantation between 12 to 36 months postoperatively. CONCLUSIONS: The German multi-center long-term outcomes compare favorably with previously published studies. Respiratory and sleepiness efficacy outcomes were sustained over 2 and 3 years, with a favorable safety profile, supporting the safety and efficacy of a chronic implantable therapy.

Previous Surgery and Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea.

OBJECTIVE: To examine whether previous palate or hypopharyngeal surgery was associated with efficacy of treatment of obstructive sleep apnea with hypoglossal nerve stimulation. STUDY DESIGN: Cohort (retrospective and prospective). SETTING: Eleven academic medical centers. SUBJECTS AND METHODS: Adults treated with hypoglossal nerve stimulation were enrolled in the ADHERE Registry. Outcomes were defined by the apnea-hypopnea index (AHI), in 3 ways: change in the AHI and 2 definitions of therapy response requiring ≥50% reduction in the AHI to a level <20 events/h (Response20) or 15 events/h (Response15). Previous palate and hypopharyngeal (tongue, epiglottis, or maxillofacial) procedures were documented. Linear and logistic regression examined the association between previous palate or hypopharyngeal surgery and outcomes, with adjustment for age, sex, and body mass index. RESULTS: The majority (73%, 217 of 299) had no previous palate or hypopharyngeal surgery, while 25% and 9% had previous palate or hypopharyngeal surgery, respectively, including 6% with previous palate and hypopharyngeal surgery. Baseline AHI (36.0 ± 15.6 events/h) decreased to 12.0 ± 13.3 at therapy titration (P < .001) and 11.4 ± 12.6 at final follow-up (P < .001). Any previous surgery, previous palate surgery, and previous hypopharyngeal surgery were not clearly associated with treatment response; for example, any previous surgery was associated with a 0.69 (95% CI: 0.37, 1.27) odds of response (Response20 measure) at therapy titration and a 0.55 (95% CI: 0.22, 1.34) odds of response (Response20 measure) at final follow-up. CONCLUSION: Previous upper airway surgery was not clearly associated with efficacy of hypoglossal nerve stimulation.

Post-approval upper airway stimulation predictors of treatment effectiveness in the ADHERE registry.

Upper airway stimulation (UAS) has been shown to reduce severity of obstructive sleep apnoea. The aim of this study was to identify predictors of UAS therapy response in an international multicentre registry.Patients who underwent UAS implantation in the United States and Germany were enrolled in an observational registry. Data collected included patient characteristics, apnoea/hypopnoea index (AHI), Epworth sleepiness scale (ESS), objective adherence, adverse events and patient satisfaction measures. Post hoc univariate and multiple logistic regression were performed to evaluate factors associated with treatment success.Between October 2016 and January 2018, 508 participants were enrolled from 14 centres. Median AHI was reduced from 34 to 7 events·h-1, median ESS reduced from 12 to 7 from baseline to final visit at 12-month post-implant. In post hoc analyses, for each 1-year increase in age, there was a 4% increase in odds of treatment success. For each 1-unit increase in body mass index (BMI), there was 9% reduced odds of treatment success. In the multivariable model, age persisted in serving as statistically significant predictor of treatment success.In a large multicentre international registry, UAS is an effective treatment option with high patient satisfaction and low adverse events. Increasing age and reduced BMI are predictors of treatment response.

Upper Airway Stimulation for Obstructive Sleep Apnea: Results from the ADHERE Registry.

Objective Upper airway stimulation (UAS) is an alternative treatment option for patients unable to tolerate continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea (OSA). Studies support the safety and efficacy of this therapy. The aim of this registry is to collect retrospective and prospective objective and subjective outcome measures across multiple institutions in the United States and Germany. To date, it represents the largest cohort of patients studied with this therapy. Study Design Retrospective and prospective registry study. Setting Ten tertiary care hospitals in the United States and Germany. Subjects and Methods Patients were included who had moderate to severe OSA, were intolerant to CPAP, and were undergoing UAS implantation. Baseline demographic and sleep study data were collected. Objective and subjective treatment outcomes, adverse events, and patient and physician satisfaction were reviewed. Results The registry enrolled 301 patients between October 2016 and September 2017. Mean ± SD AHI decreased from 35.6 ± 15.3 to 10.2 ± 12.9 events per hour ( P < .0001), and Epworth Sleepiness Scale scores decreased from 11.9 ± 5.5 to 7.5 ± 4.7 ( P < .0001) from baseline to the posttitration visit. Patients utilized therapy for 6.5 hours per night. There were low rates of procedure- and device-related complications. Clinical global impression scores demonstrated that the majority of physicians (94%) saw improvement in their patients' symptoms with therapy. The majority of patients (90%) were more satisfied with UAS than CPAP. Conclusions Across a multi-institutional registry, UAS therapy demonstrates significant improvement in subjective and objective OSA outcomes, good therapy adherence, and high patient satisfaction.

Upper Airway Stimulation for Obstructive Sleep Apnea: 5-Year Outcomes.

Objective To present 5-year outcomes from a prospective cohort of patients with obstructive sleep apnea (OSA) who were treated with upper airway stimulation (UAS) via a unilateral hypoglossal nerve implant. Study Design A multicenter prospective cohort study. Setting Industry-supported multicenter academic and clinical trial. Methods From a cohort of 126 patients, 97 completed protocol, and 71 consented to a voluntary polysomnogram. Those having continuous positive airway pressure failure with moderate to severe OSA, body mass index <32 kg/m2, and no unfavorable collapse on drug-induced sleep endoscopy were enrolled in a phase 3 trial. Prospective outcomes included apnea-hypopnea index (AHI), oxygen desaturation index, and adverse events, as well as measures of sleepiness, quality of life, and snoring. Results Patients who did and did not complete the protocol differed in baseline AHI, oxygen desaturation index, and Functional Outcomes of Sleep Questionnaire scores but not in any other demographics or treatment response measures. Improvement in sleepiness (Epworth Sleepiness Scale) and quality of life was observed, with normalization of scores increasing from 33% to 78% and 15% to 67%, respectively. AHI response rate (AHI <20 events per hour and >50% reduction) was 75% (n = 71). When a last observation carried forward analysis was applied, the responder rate was 63% at 5 years. Serious device-related events all related to lead/device adjustments were reported in 6% of patients. Conclusions Improvements in sleepiness, quality of life, and respiratory outcomes are observed with 5 years of UAS. Serious adverse events are uncommon. UAS is a nonanatomic surgical treatment with long-term benefit for individuals with moderate to severe OSA who have failed nasal continuous positive airway pressure.

Outcome after one year of upper airway stimulation for obstructive sleep apnea in a multicenter German post-market study.

OBJECTIVE/HYPOTHESIS: Upper airway stimulation (UAS) of the hypoglossal nerve has been implemented in the routine clinical practice for patients with moderate-to-severe obstructive sleep apnea (OSA) who could not adhere to continuous positive airway pressure. This study reports objective and patient-reported outcome after 12 months of implantation. STUDY DESIGN: Multicenter prospective single-arm study. METHODS: Consecutive patients who received the UAS system (Inspire Medical Systems, Inc., Minneapolis, Minnesota, Maple Grove, MN, U.S.A.) were enrolled in three German centers. Key study exclusion criteria included body mass index > 35 kg/m2 , apnea-hypopnea index (AHI) < 15 or > 65, or complete concentric collapse at the soft palate during sedated endoscopy. Data collection at 6- and 12-month visit include home sleep test and patient-reported outcome measures. RESULTS: Among the total of 60 participants, the median AHI reduced from 28.6 to 9.5 from baseline to 12 months. Patient-reported outcome measured in Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire both improved significantly from baseline to 12 months. The average usage time was 39.1 ± 14.9 hours per week among all participants based on recordings by the implanted device. One patient requested a removal of the device for cosmetic and other personal reasons and was completed without sequelae. CONCLUSION: This study supported that UAS is a safe and effective treatment option for patients with OSA in routine clinical practice. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:509-515, 2018.

Upper Airway Stimulation for Obstructive Sleep Apnea: Patient-Reported Outcomes after 48 Months of Follow-up.

Objective To assess patient-based outcomes of participants in a large cohort study-the STAR trial (Stimulation Therapy for Apnea Reduction)-48 months after implantation with an upper airway stimulation system for moderate to severe obstructive sleep apnea. Study Design A multicenter prospective cohort study. Setting Industry-supported multicenter academic and clinical setting. Subjects Participants (n = 91) at 48 months from a cohort of 126 implanted participants. Methods A total of 126 participants received an implanted upper airway stimulation system in a prospective phase III trial. Patient-reported outcomes at 48 months, including Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), and snoring level, were compared with preimplantation baseline. Results A total of 91 subjects completed the 48-month visit. Daytime sleepiness as measured by ESS was significantly reduced ( P = .01), and sleep-related quality of life as measured by FOSQ significantly improved ( P = .01) when compared with baseline. Soft to no snoring was reported by 85% of bed partners. Two patients required additional surgery without complication for lead malfunction. Conclusion Upper airway stimulation maintained a sustained benefit on patient-reported outcomes (ESS, FOSQ, snoring) at 48 months in select patients with moderate to severe obstructive sleep apnea.

Outcomes of Upper Airway Stimulation for Obstructive Sleep Apnea in a Multicenter German Postmarket Study.

Objective Selective stimulation of the hypoglossal nerve is a new surgical therapy for obstructive sleep apnea, with proven efficacy in well-designed clinical trials. The aim of the study is to obtain additional safety and efficacy data on the use of selective upper airway stimulation during daily clinical routine. Study Design Prospective single-arm study. Setting Three tertiary hospitals in Germany (Munich, Mannheim, Lübeck). Subjects and Methods A multicenter prospective single-arm study under a common implant and follow-up protocol took place in 3 German centers (Mannheim, Munich, Lübeck). Every patient who received an implant of selective upper airway stimulation was included in this trial (apnea-hypopnea index ≥15/h and ≤65/h and body mass index <35 kg/m2). Before and 6 months after surgery, a 2-night home sleep test was performed. Data regarding the safety and efficacy were collected. Results From July 2014 through October 2015, 60 patients were included. Every subject reported improvement in sleep and daytime symptoms. The average usage time of the system was 42.9 ± 11.9 h/wk. The median apnea-hypopnea index was significantly reduced at 6 months from 28.6/h to 8.3/h. No patient required surgical revision of the implanted system. Conclusion Selective upper airway stimulation is a safe and effective therapy for patients with obstructive sleep apnea and represents a powerful option for its surgical treatment.

Targeted hypoglossal nerve stimulation for the treatment of obstructive sleep apnea: Six-month results.

OBJECTIVES/HYPOTHESIS: This feasibility study was designed to show the preliminary safety and efficacy of targeted hypoglossal neurostimulation (THN), and to identify baseline predictors of successful therapy. STUDY DESIGN: Open-label, prospective, multicenter, single-arm cohort study, conducted at seven centers in the U.S.A. and Europe. METHODS: Forty-six participants with moderate to severe obstructive sleep apnea (OSA), failing or intolerant of continuous positive airway pressure, were implanted. Primary (Apnea-Hypopnea Index [AHI], Oxygen Desaturation Index [ODI]) and secondary (Arousal Index, Epworth Sleepiness Scale Index, Sleep Apnea Quality of Life Index) outcomes were measured at baseline and compared at 6 months. Data were analyzed to identify participant characteristics that would predict success with therapy. RESULTS: Sixty-seven adverse events (AEs) were observed among 36 participants; most of the AEs were related to the implant procedure and resolved without sequelae; one device replacement was necessary. Forty-three participants showed significant (P < .01) decreases in both AHI and ODI at 6 months; 35% (15 of 43) met criteria for AHI responders and 40% (17 of 43) for ODI responders. Significant improvement was observed in all the secondary endpoints. Predictors-of-success selection criteria were identified as baseline AHI < 65/hr, baseline apnea index ≤ 30, baseline body mass index < 35, and <15 events/hr of SpO2 decrease > 10%. Seven participants met these criteria; 86% (6 of 7) were AHI responders and 86% (6 of 7) were ODI responders, indicating that THN therapy can be efficacious in a carefully selected population of OSA patients. CONCLUSIONS: This feasibility study suggests that THN therapy is likely to be safe and effective in selected patients. LEVEL OF EVIDENCE: 2b Laryngoscope, 126:2618-2623, 2016.

Three-Year Outcomes of Cranial Nerve Stimulation for Obstructive Sleep Apnea: The STAR Trial.

OBJECTIVE: To describe the 36-month clinical and polysomnography (PSG) outcomes in an obstructive sleep apnea (OSA) cohort treated with hypoglossal cranial nerve upper airway stimulation (UAS). STUDY DESIGN: A multicenter prospective cohort study. SETTING: Industry-supported multicenter academic and clinical setting. SUBJECTS: Participants (n = 116) at 36 months from a cohort of 126 implanted participants. METHODS: Participants were enrolled in a prospective phase III trial evaluating the efficacy of UAS for moderated to severe OSA. Prospective outcomes included apnea-hypopnea index, oxygen desaturation index, other PSG measures, self-reported measures of sleepiness, sleep-related quality of life, and snoring. RESULTS: Of 126 enrolled participants, 116 (92%) completed 36-month follow-up evaluation per protocol; 98 participants additionally agreed to a voluntary 36-month PSG. Self-report daily device usage was 81%. In the PSG group, 74% met the a priori definition of success with the primary outcomes of apnea-hypopnea index, reduced from the median value of 28.2 events per hour at baseline to 8.7 and 6.2 at 12 and 36 months, respectively. Similarly, self-reported outcomes improved from baseline to 12 months and were maintained at 36 months. Soft or no snoring reported by bed partner increased from 17% at baseline to 80% at 36 months. Serious device-related adverse events were rare, with 1 elective device explantation from 12 to 36 months. CONCLUSION: Long-term 3-year improvements in objective respiratory and subjective quality-of-life outcome measures are maintained. Adverse events are uncommon. UAS is a successful and appropriate long-term treatment for individuals with moderate to severe OSA.

Upper Airway Stimulation for Obstructive Sleep Apnea: Self-Reported Outcomes at 24 Months.

OBJECTIVES: To evaluate the long-term (24-mo) effect of cranial nerve upper airway stimulation (UAS) therapy on patient-centered obstructive sleep apnea (OSA) outcome measures. METHODS: Prospective, multicenter, cohort study of 126 patients with moderate to severe OSA who had difficulty adhering to positive pressure therapy and received the surgically implanted UAS system. Outcomes were measured at baseline and postoperatively at 12 mo and 24 mo, and included self- and bedpartner-report of snoring intensity, Epworth Sleepiness Scale (ESS), and Functional Outcomes of Sleep Questionnaire (FOSQ). Additional analysis included FOSQ subscales, FOSQ-10, and treatment effect size. RESULTS: Significant improvement in mean FOSQ score was observed from baseline (14.3) to 12 mo (17.3), and the effect was maintained at 24 mo (17.2). Similar improvements and maintenance of effect were seen with all FOSQ subscales and FOSQ-10. Subjective daytime sleepiness, as measured by mean ESS, improved significantly from baseline (11.6) to 12 mo (7.0) and 24 mo (7.1). Self-reported snoring severity showed increased percentage of "no" or "soft" snoring from 22% at baseline to 88% at 12 mo and 91% at 24 mo. UAS demonstrated large effect size (> 0.8) at 12 and 24 mo for overall ESS and FOSQ measures, and the effect size compared favorably to previously published effect size with other sleep apnea treatments. CONCLUSIONS: In a selected group of patients with moderate to severe OSA and body mass index ≤ 32 kg/m2, hypoglossal cranial nerve stimulation therapy can provide significant improvement in important sleep related quality-of-life outcome measures and the effect is maintained across a 2-y follow-up period.

Randomized controlled withdrawal study of upper airway stimulation on OSA: short- and long-term effect.

OBJECTIVE: To assess the efficacy and durability of upper airway stimulation via the hypoglossal nerve on obstructive sleep apnea (OSA) severity including objective and subjective clinical outcome measures. STUDY DESIGN: A randomized controlled therapy withdrawal study. SETTING: Industry-supported multicenter academic and clinical setting. SUBJECTS: A consecutive cohort of 46 responders at 12 months from a prospective phase III trial of 126 implanted participants. METHODS: Participants were randomized to either therapy maintenance ("ON") group or therapy withdrawal ("OFF") group for a minimum of 1 week. Short-term withdrawal effect as well as durability at 18 months of primary (apnea hypopnea index and oxygen desaturation index) and secondary outcomes (arousal index, oxygen desaturation metrics, Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, snoring, and blood pressure) were assessed. RESULTS: Both therapy withdrawal group and maintenance group demonstrated significant improvements in outcomes at 12 months compared to study baseline. In the randomized assessment, therapy withdrawal group returned to baseline, and therapy maintenance group demonstrated no change. At 18 months with therapy on in both groups, all objective respiratory and subjective outcome measures showed sustained improvement similar to those observed at 12 months. CONCLUSION: Withdrawal of therapeutic upper airway stimulation results in worsening of both objective and subjective measures of sleep and breathing, which when resumed results in sustained effect at 18 months. Reduction of obstructive sleep apnea severity and improvement of quality of life were attributed directly to the effects of the electrical stimulation of the hypoglossal nerve.