Evaluation of Surgical Learning Curve Effect on Obstructive Sleep Apnea Outcomes in Upper Airway Stimulation.

OBJECTIVE: An increasing number of facilities offer Upper Airway Stimulation (UAS) with varying levels of experience. The goal was to quantify whether a surgical learning curve exists in operative or sleep outcomes in UAS. METHODS: International multi-center retrospective review of the ADHERE registry, a prospective international multi-center study collecting UAS outcomes. ADHERE registry centers with at least 20 implants and outcomes data through at least 6-month follow-up were reviewed. Cases were divided into two groups based on implant order (the first 10 or second 10 consecutive implants at a given site). Group differences were assessed using Mann-Whitney U-tests, Chi-squared tests, or Fisher's Exact tests, as appropriate. A Mann-Kendall trend test was used to detect if there was a monotonic trend in operative time. Sleep outcome equivalence between experience groups was assessed using the two one-sided tests approach. RESULTS: Thirteen facilities met inclusion criteria, contributing 260 patients. Complication rates did not significantly differ between groups (P = .808). Operative time exhibited a significant downward trend (P < .001), with the median operative time dropping from 150 minutes for the first 10 implants to 134 minutes for the subsequent 10 implants. The decrease in AHI from baseline to 12-month follow-up was equivalent between the first and second ten (22.8 vs 21.2 events/hour, respectively, P < .001). Similarly, the first and second ten groups had equivalent ESS decreases at 6 months (2.0 vs 2.0, respectively, P < .001). ESS outcomes remained equivalent for those with data through 12-months. CONCLUSIONS: Across the centers' first 20 implants, an approximately 11% reduction operative time was identified, however, no learning curve effect was seen for 6-month or 12-month AHI or ESS over the first twenty implants. Ongoing monitoring through the ADHERE registry will help measure the impact of evolving provider and patient specific characteristics as the number of implant centers increases.

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.

Increasing preoperative apnea severity improves upper airway stimulation response in OSA treatment.

OBJECTIVE: Examine the patient characteristics of those undergoing upper airway stimulation (UAS) for the treatment of continuous positive airway pressure (CPAP)-refractive obstructive sleep apnea (OSA) at a tertiary care medical center to determine objective clinical predictors of success. METHODS: Retrospective chart review of the first 25 consecutive patients between August 2015 and December 2016 treated with UAS at a tertiary care academic center. Demographic data, medical and sleep history, pre- and postoperative polysomnography data, and sleep endoscopy findings were collected. Statistical analysis was performed using two-sided t test with bivariate and linear regression analysis. RESULTS: In our cohort of 25 patients, mean age was 67.5 ± 7.6 years, and mean body mass index (BMI) was 28.2 ± 3.8 kg/m2 with 42% female. One patient was excluded from analysis for unmasking of complete central apnea with therapy. AHI decreased by a mean of 33.8 events/hour following treatment (95% confidence interval: 25.8 to 41.7, P < 0.001). Preintervention AHI was associated with therapy response, with each point of preintervention AHI leading to an average decrease of 1.03 points (P < 0.001). Eighty-three percent of patients achieved a treatment AHI < 5, whereas 92% achieved an AHI < 10. Mean device use was 49.5 ± 10.4 hours per week. Ninety-two percent of patients were discharged the day of surgery. No major adverse events occurred. CONCLUSION: UAS continues to gain popularity for the treatment of CPAP-refractive OSA; therefore, identification of predictors of success is crucial. Our study, although small, suggests that more severe preintervention AHI does not preclude significant therapy response and may expand the inclusion criteria for UAS, meriting further investigation. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:556-560, 2020.

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.

Upper Airway Stimulation Response in Older Adults with Moderate to Severe Obstructive Sleep Apnea.

OBJECTIVE: To evaluate the impact of age on safety, efficacy, and usage of upper airway stimulation (UAS). STUDY DESIGN: Multicenter observational study. SETTING: Thirteen US hospitals and 3 German hospitals. SUBJECTS AND METHODS: The ADHERE registry is a multicenter database enrolling patients undergoing UAS implantation from October 2016 to April 2018. Outcome measures included the Epworth Sleepiness Scale, apnea-hypopnea index (AHI), therapy usage, and complications. Data were segmented by age (<65 vs ≥65 years). RESULTS: Younger adults (n = 365) were a mean ± SD 52.7 ± 7.9 years old and 82% male, with a body mass index of 29.6 ± 3.8. Older adults (n = 235) were 71.1 ± 4.8 years old and 71% male, with a body mass index of 28.8 ± 3.8. Baseline AHI was similar (younger, 36.2 ± 15.9; older, 36.1 ± 14.8). Both groups had lower AHI at 12 months versus baseline (P < .001), but the older group showed a greater reduction (7.6 ± 6.9 vs 11.9 ± 13.4, P = .01). The Epworth Sleepiness Scale score decreased from 12.3 ± 5.4 to 7.1 ± 4.8 (P < .001) among younger adults and from 10.7 ± 5.7 to 6.3 ± 4.4 (P < .001) among older adults. Usage was slightly higher among older adults (6.0 ± 2.0 vs 5.4 ± 2.1 hours/night, P = .02). Surgical time was similar between younger patients (2.4 ± 0.7 hours) and older patients (2.3 ± 0.7 hours, P = .40), with comparably low complications. CONCLUSION: AHI reduction and therapy usage were found to be somewhat higher among patients aged ≥65 years who were treated with UAS. Surgical complications were low, in contrast to traditional sleep surgery.

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.

Early feasibility of hypoglossal nerve upper airway stimulator in patients with cardiac implantable electronic devices and continuous positive airway pressure-intolerant severe obstructive sleep apnea.

BACKGROUND: Implantable hypoglossal nerve upper airway stimulation (HNS) is a novel strategy approved by the US Food and Drug Administration for the management of moderate-to-severe obstructive sleep apnea (OSA) in patients with continuous positive airway pressure therapy intolerance or failure. Because of the proximity of a cardiac implantable electronic device (CIED) to this stimulator, interaction between these devices is theoretically possible. OBJECTIVE: The purpose of this study was to assess interactions between an implantable HNS device and a CIED. METHODS: We retrospectively analyzed 14 ad hoc patients with continuous positive airway pressure-intolerant, moderate-to-severe OSA and pre-existing transvenous CIEDs undergoing HNS implantation (Inspire II, Inspire Medical Systems). We assessed these devices for their pre and postimplant OSA outcomes and for possible device-device interaction. All patients were followed up for 1 year. RESULTS: Of the 14 patients, 9 had a pacemaker (8 dual-chamber, 1 single-chamber), 4 had an implantable cardioverter-defibrillator (2 dual-chamber, 1 single-chamber), and 1 had a cardiac resynchronization therapy device. All the HNS devices were implanted on the opposite side of the CIED. All CIEDs were programmed bipolar. HNS were programmed either unipolar or bipolar. During implant, intraoperative testing was performed to confirm that bipolar and unipolar HNS stimulation did not impact CIED sensing. During the follow-up period, no oversensing episodes were noted on the CIEDs. CONCLUSION: In this early experience, simultaneous use of a novel hypoglossal nerve upper airway stimulation device with transvenous CIEDs seems to be safe, effective, and without any device-device interactions.

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.