Treatment Acceptance Based on Patient Qualification- The Predictor Device®

Over the last 20 years there has been an ever increasing use of oral appliances for the treatment of obstructive sleep apnea (OSA) and sleep disordered breathing (SDB). In Scandinavian countries the preferred interventional therapy for the mild to moderate sleep apnea patient has been an oral appliance due to improved patient compliance. Only when the patient has severe sleep apnea or when there are other clinical factors to consider is CPAP recommended. In the United States the American Academy of Sleep Medicine (AASM) has recommended Oral Appliance Therapy as a first line therapy for mild to moderate OSA since 2006.

In America the dominance of CPAP therapy is quickly surrendering to oral appliances due to compliance concerns, changes in insurance

Home sleep test with Nox T3 and ApneaRx

reimbursement and greater access to home sleep testing. Many clinicians have been reluctant to prescribe a costly custom fabricated oral appliance due to concerns about effectiveness of oral appliances. The true barrier to oral appliances has been the difficulty to predict a successful outcome.

Today we have now have ApneaRx®, The Predictor Device® which for a low cost can accurately predict a patient’s success with an oral appliance. ApneaRx is a prefabricated oral appliance that can be boiled, cooled and custom fit in less than 5 minutes. Once fit, the device can be micro adjusted in 1mm increments, which meets prescribed AASM criteria. I find this product particularly interesting because the ApneaRx is designed as a temporary device for predicting success with a custom oral appliance however it is robust and durable enough to be worn every night. The importance of this last feature is that oral appliance therapy is critically affected by the condition of the patient’s muscles and ligaments which can relax and adapt over time. It is suggested that the patient wear the appliance for 2 weeks before a titration study is undertaken in order for this adapted condition to occur. ApneaRx is light comfortable and predictive of success with a more expensive custom fabricated oral appliance.

Unlike those considering CPAP devices, which patients can “try before they buy,” those considering OA treatment must rely on the expertise of their physician in being able to predict treatment success and be willing to pay without certainty about the outcome. CPAP therapy is so well suited to the in lab sleep study or polysomnogram that the patient and their physician are not only confident their OSA is resolved with the CPAP, but a prescription can be written with a therapeutic pressure.
In order to try a custom oral appliance for the treatment of OSA a patient prior to ApneaRx required a custom oral appliance fabricated at a cost of thousands of dollars with no guarantee of success. Consistent in all studies of Oral Appliance therapy is that OSA is not adequately alleviated in all patients. Naturally patients and their physicians are concerned that a large investment without any ability to predict success with the oral appliance makes a decision difficult, and to some the decision feels risky.

So who are these patients? Studies indicate that there are a tremendous number of patients for whom the promise of a good night sleep using CPAP did not translate into nightly usage. CPAP acceptance and compliance are between 35% - 50%. A significant number of patients (ranging from 30% to 80% in various studies) demonstrate an average CPAP usage of less than 4 hours per night.[1][2]

Great candidates for oral appliance therapy also tend to have a positional component to their condition. Supine-predominant OSA (a higher AHI in supine compared to lateral sleeping position) has been considered favorable for treatment success.[3] Some patients actually are predisposed to oral appliance therapy based on their unique facial features. Craniofacial features assessed by lateral cephalometry, including shorter soft palate length, lower hyoid bone position, greater angle between the cranial base and mandibular plane, and a retrognathic mandible, are also associated with favorable treatment outcome.[4] Clearly in order to serve the need of treating this patient population with a therapy that they could accept from a clinical and lifestyle perspective a predictive appliance needed to be developed. This type appliance not only required the ability to be fabricated at low cost but also titrated in 1mm increments and be easily adjusted in a diagnostic setting like a sleep lab or in a patients home, ApneaRx fits all of these criteria.

A pilot study by a team of clinicians from Kaiser Permanente in Fontana CA evaluated 117 patients and found the ApneaRx 100% predictive of success with a custom oral appliance. [5] Over time dentists have tried many ways to predict success with an oral appliance from cone beam imaging, to acoustic resonance, to kinesiology there just never seemed to be a low cost predictor of success with an oral appliance for obstructive sleep apnea. The clinical challenge has always seemed to be that ‘the patient was fitted while awake and treated while asleep.’[6]

Best practice standards require that a Board Certified Sleep Physician form a medical diagnosis of OSA, before treatment is initiated. It is important that baseline values be established and a treatment protocol followed that takes into account degree and severity of the patient’s condition. Single-night titration methods, allowing advancement of the mandible during sleep, have shown more promise in indicating likely treatment success and therapeutic level of advancement in a small number of patients using prototype devices. This method involves use of a remotely controlled intraoral device during an

attended sleep study to incrementally advance the mandible until sleep disordered breathing events are eliminated, analogous to a CPAP pressure titration study.[1]If a custom oral appliance is the selected therapy, a follow-up Polysomnogram (PSG) or Home Sleep Test (HST) must be ordered to confirm that post treatment values fall into an acceptable range.

In summary, while the US sleep apnea market has been built by selecting CPAP as the first line of interventional therapy, oral appliances are expected to  equal, or surpass CPAP therapy in a few short years,  as is now the established standard of care and first line interventional therapy for many other countries. The customized nature of oral appliance therapy requires additional diagnostics be performed to assure the physician and the patient that the therapy is in fact a viable option and to confirm that the investment in the custom oral appliance is one that will meet, or exceed the minimal clinical requirements.  The ApneaRx®, ‘The Predictor®’ is the first and only such device with a peer reviewed independent clinical study that validates oral appliance therapy.  It is no wonder that many physicians are now writing their prescriptions, ApneaRx / CPAP therapy.

[1] Kribbs NB, Pack AI, Kline LR, et al., authors. Objective measurement of patterns of nasal CPAP use by patients with obstructive sleep apnea. Am Rev Respir Dis. 1993;147:887–95

[2] Reeves-Hoche MK, Meck R, Zwillich CW, authors. Nasal CPAP: an objective evaluation of patient compliance. Am J Respir Crit Care Med. 1994;149:149–54

[3] Sutherland K; Vanderveken OM; Tsuda H; Marklund M; Gagnadoux F; Kushida CA; Cistulli PA; on behalf of the ORANGE-Registry. Oral appliance treatment for obstructive sleep apnea: an update. J Clin Sleep Med 2014;10(2):215-227.

[4] Sutherland K; Vanderveken OM; Tsuda H; Marklund M; Gagnadoux F; Kushida CA; Cistulli PA; on behalf of the ORANGE-Registry. Oral appliance treatment for obstructive sleep apnea: an update. J Clin Sleep Med 2014;10(2):215-227.

[5] Dennis Hwang, Jeremiah Chang Feasibility Pilot Evaluating the Use of Pre-Fabricated Titratable Mandibular Poster Presentation  AASM  2013

[6] Randy Clare; Low Cost-High Value "Predictor Device" for Oral Appliance Therapy- Economics or Oral Appliance Therapy; SleepScholar.com online 2015 3.31