Medical Policy: 07.01.68
Original Effective Date: May 2015
Reviewed: April 2017
Revised: April 2017
Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.
This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.
Obstructive sleep apnea (OSA) is serious, potentially life threatening condition and is characterized by repeated episodes of airway collapse (apnea) or narrowing (hypopnea) during sleep, often leading to hypoxemia and hypercapnia. Episodes are usually terminated by a brief arousal, after which sleep resumes and the cycle repeats itself.
Untreated OSA has many potential consequences and adverse clinical associations, including excessive daytime sleepiness, impaired daytime function, metabolic dysfunction, and an increased risk of cardiovascular disease and mortality. The goals of OSA therapy are to resolve signs and symptoms of OSA, improve sleep quality, and normalize the apnea hypopnea index (AHI) and oxyhemoglobin saturation levels. OSA should be approached as a chronic disease that requires long term, multidisciplinary management.
Continuous positive airway pressure (CPAP) is the preferred treatment option for most patients with OSA. In patients who prefer not to use positive airway pressure (PAP) or who fail to respond to it, oral appliances or surgery to correct anatomic structures in the upper airway are additional treatment alternatives. Evidence is lacking related to upper airway surgery long term effectiveness. Therefore, new approaches to the treatment of OSA is desired and the use of implanted hypoglossal nerve stimulation has been studied as a potential treatment option for the treatment of OSA.
Stimulation of the hypoglossal nerve contracts the genioglossus muscle, the largest upper airway dilator muscle. This causes the tongue protrusion and stiffening of the anterior pharyngeal wall, potentially decreasing apneic events. Hypoglossal nerve stimulation systems include an implantable neurostimulator, stimulating leads and electrodes. Stimulation systems such as Inspire II Upper Airway Stimulation System include respiratory sensing leads that permit intermittent stimulation during respiration. Stimulation parameters are titrated during an in-laboratory sleep study (polysomnography) and can be adjusted by the patient during home use. The device is turned on only during sleep periods.
The Inspire II Upper Airway Stimulation therapy is intended to treat moderate to severe obstructive sleep apnea (OSA). The device is designed for use in patients who are unable or unwilling to use CPAP device. Inspire’s construction and implantation are similar to those of a pacemaker: a surgeon implants the device containing a neurostimulator subcutaneously in the patient’s chest with one lead attached to the patient’s hypoglossal nerve (cranial nerve XII) at the base of the tongue and one lead implanted in the patient’s chest. The lead in the chest consists of a pressure sensor that detects breathing. Information about the respiration rate is relayed to the device, which stimulates the hypoglossal nerve in the tongue. When stimulated, the tongue moves forward, thus opening the airway. The patient can operate the device by remote control, which the patient activates before going to sleep. The device turns on after 20 minutes to minimize disrupting the patient’s sleep onset; the device turns off via remote when the patient wakes up.
The primary study for this device is the STAR trial, 126 patients with moderate to severe OSA (AHI to 20 to 50 events per hour) who had difficulty accepting or adhering to CPAP therapy. This trial involved two phases and was reported in multiple publications. The first phase was a 12 month case series in which all enrolled patients received the device; the second phase was a randomized trial that included only those patients who had responded well to the device during the first phase. Key exclusion criteria included a body mass index >32 mg/m2, uncontrolled hypertension, positional OSA, and the presence of complete concentric pharyngeal collapse on screening drug-induced sleep endoscopy.
The results of the STAR trial’s phase I indicated that overall, patients improved with respect to sleep apnea symptoms. Phase II of the STAR trial demonstrated that the device itself caused the symptom improvements, since turning off the device at 12 months in half the responders resulted in their return to baseline (high) symptom levels, and turning it back on at 18 months resulted in reduced symptoms. However, one issue of concern is the rate of responders. In the STAR trial, only 37% of enrolled patients were deemed to have responded well. Another issue is related to patient selection, surgeons may disagree about who is a good candidate for this device. In one of the STAR publications, four surgeons reviewed video clips from 63 drug-induced sleep endoscopy procedures. The four surgeons were in complete agreement in 44% of cases regarding whether a patient was a good candidate for this device. This indicates there is room for improvement in patient suitability assessments.
Woodson et. al. (2015) conducted a multicenter prospective cohort study to describe the three year outcomes of hypoglossal cranial nerve upper airway stimulation for obstructive sleep apnea: the STAR trial. The participants were enrolled in a prospective phase III trial evaluating the efficacy of UAS for moderate 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. Of the 126 participants enrolled 116 completed 36 month follow up evaluation per protocol: 98 participants agreed to a voluntary 36 month PSG. Self-reported daily device usage was 81%. In the PSG group, 74% met the 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. 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. The authors concluded this study provides prospective results at 3 years and indicates substantial use and clinical improvement in individuals who have moderate to severe OSA, who have failed conventional therapy, and who met favorable inclusion criteria. There were 3 year improvements in objective respiratory and subjective quality of life outcome measures that were maintained. Adverse events were uncommon. However, weakness of the current report include a potential selection bias in the group agreeing to have sleep studies and the lack of a control group. The lack of a control group limits the validity of the results of this study.
Certal et al. (2015) conducted a systematic review of the evidence regarding the efficacy and safety of hypoglossal nerve stimulation as an alternative therapy in the treatment of OSA. Studies were included that evaluated the efficacy of hypoglossal nerve stimulation to treat OSA in adults with outcomes of apnea-hypopnea (AHI), oxygen desaturation index (ODI), and effect on daytime sleepiness (Epworth Sleepiness Scale [ESS]). Tests for heterogeneity and subgroup analysis were performed. A total of six prospective studies with 200 patients were included in this review. At 12 months, the pooled fixed effects analysis demonstrated statistically significant reductions in AHI, ODI, and ESS mean difference of -17.51 (95% CI: -20.69 to -14.34); -13.73 (95% CI: -16.87 to -10.58), and -4.42 (95% CI: -5.39 to -3.44), respectively. Similar significant reductions were observed at 3 and 6 months. Overall, the AHI was reduced between 50% and 57%, and the ODI was reduced between 48% and 52%. Despite using different hypoglossal nerve stimulators in each subgroup analysis, no significant heterogeneity was found in any of the comparisons, suggesting equivalent efficacy regardless of the system in use. The authors reported that further studies comparing hypoglossal nerve stimulation with conventional therapies are needed to definitively evaluate outcomes.
Patients who fail or cannot comply with conservative treatment may be candidates for surgical interventions for the treatment of moderate to severe obstructive sleep apnea (OSA). Implanted hypoglossal nerve stimulation has been studied as a potential treatment option for the treatment of OSA. Based on the published medical literature the overall quality of the evidence evaluating hypoglossal nerve stimulation is very low. In the largest study to date, two thirds of patients who met inclusion criteria for AHI, body mass index (BMI), and favorable pattern of palatal collapse met the study definition of success. However, the role of nerve stimulation among the surgical procedures for OSA treatment is uncertain. Randomized controlled trials (RCTs) comparing hypoglossal nerve stimulation to conventional surgical procedures are needed to evaluate benefits and harms. Also, the optimal patient selection criteria for the use of hypoglossal nerve stimulation has not been defined and additional studies are needed to define the patient population that is likely to respond to hypoglossal nerve stimulation. The evidence is insufficient to determine the effects of this technology on net health outcomes.
In 2010, the American Academy of Sleep Medicine issued a practice parameter for the surgical modifications of the upper airway for obstructive sleep apnea in adults, this practice parameter does not mention or indicate the use of hypoglossal nerve stimulation as a surgical treatment option for the treatment of obstructive sleep apnea.
In 2014, the American Academy of Otolaryngology Head and Neck Surgery revised their position statement: surgical management of obstructive sleep apnea, this position statement does not mention or indicate the use of hypoglossal nerve stimulation as a surgical management treatment option for treatment of obstructive sleep apnea.
In 2016, the American Academy of Otolaryngology Head and Neck Surgery issued a position statement on hypoglossal nerve stimulation for treatment of obstructive sleep apnea (OSA) which states “The American Academy of Otolaryngology Head and Neck Surgery considers upper airway stimulation (UAS) via the hypoglossal nerve for the treatment of adult obstructive sleep apnea syndrome to be an effective second-line treatment of moderate to severe obstructive sleep apnea in patient who are intolerant or unable to achieve benefit with positive pressure therapy (PAP). Not all adult patients are candidates for UAS therapy and appropriate polysomnographic, age, BMI and objective upper airway evaluation measures are required for proper patient selection.”
In 2011, Apnex Medical received FDA approval to conduct a randomized investigational device exemption trial for the Hypoglossal Nerve Stimulation (HGNS) System. In 2013, this device was no longer available.
In May 2014, The Inspire II Upper Airway Stimulator (Inspire Medical Systems, Inc, Maple Grove, MN) received FDA approval. The device is used to treat a subset of patients with moderate to severe obstructive sleep apnea (OSA) (apnea hypopnea index (AHI) of greater or equal to 20 and less than or equal to 65). Inspire Upper Airway System is used in adult patients 22 years of age and older who have confirmed to fail or cannot tolerate positive airway pressure (PAP) treatments (such as continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BPAP) machines) and who do not have a complete concentric collapse of the soft palate level. PAP failure is defined as an inability to eliminate OSA (AHI of greater than 20 despite PAP usage) and PAP tolerance is defined as 1) inability to use PAP (greater than 5 nights per week of usage; usage defined as greater than 4 hours of use per night); or 2) unwillingness to use PAP (for example, a patient returns the PAP system after attempting to use it).
The Inspire Upper Airway Stimulator is contraindicated for:
In November 2014, ImThera Medical, Inc., received FDA approval to conduct investigational device exemption trial for its THN3 clinical study. The THN3 study will evaluate the safety and effectiveness of the aura6000 system for moderate to severe OSA in individuals who are unable to comply or unwilling to try PAP therapy or other OSA treatments. Data from this clinical study will be used to support a Pre-Market Approval (PMA) application for the aura6000 system.
Implantable hypoglossal nerve stimulation is considered investigational for all indications, including but not limited to the treatment of obstructive sleep apnea (OSA).
Based on the published medical literature the overall quality of the evidence evaluating hypoglossal nerve stimulation is very low. In the largest study to date, two thirds of patients who met inclusion criteria for AHI, body mass index (BMI), and favorable pattern of palatal collapse met the study definition of success. However, the role of nerve stimulation among the surgical procedures for OSA treatment is uncertain. Randomized controlled trials (RCTs) comparing hypoglossal nerve stimulation to conventional surgical procedures are needed to evaluate benefits and harms. Also, the optimal patient selection criteria for the use of hypoglossal nerve stimulation has not been defined and additional studies are needed to define the patient population that is likely to respond to hypoglossal nerve stimulation. The evidence is insufficient to determine the effects of this technology on net health outcomes.
To report provider services, use appropriate CPT* codes, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.
Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc. They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.
*CPT® is a registered trademark of the American Medical Association.