OSANOVA is a non-randomized clinical trial which aims to compare outcomes of mandibular advancement device (MAD) and hypoglossal nerve stimulation (HGNS) therapies in moderate-to-severe OSA patients who fail, decline, or are intolerant to positive airway pressure (PAP) therapy (referred to as PAP-failing patients).

The primary aim of the study is to compare the outcomes between PAP-failing moderate-to-severe OSA patients receiving MAD and those receiving HGNS therapy. Primary Outcome measures include changes in Pittsburgh Sleep Quality Index (PSQI) scores.

Secondary aims will help us describe the outcomes between PAP-failing moderate-to-severe OSA patients receiving MAD and those receiving HGNS therapy. Secondary outcome measures include:

• adverse events,
• Epworth Sleepiness Scale (ESS),
• Symptoms of Nocturnal Obstruction and Related Events (SNORE-25),
• patient-reported satisfaction,
• CGI-Improvement,
• the rate of subjects re-selecting the treatment, and
• the rate of subjects recommending the treatment. and
• changes in sleep study metrics (i.e., AHI, ODI, mean arterial saturation, and Time<90%),

The study will enroll and follow a cohort of PAP-failing patients receiving MAD therapy and a second cohort receiving HGNS therapy. Baseline and post-intervention patient-reported outcome measures (PROMs) and standard sleep study parameters to evaluate and compare treatment efficacy will be captured.

Both MAD and HGNS are accepted treatments for moderate OSA patients following PAP intolerance, refusal, or failure. Current decision-making is based heavily on patient preference rather than well-defined evidence-based recommendations. Choosing the right therapy is a crucial aspect of treatment for OSA, a chronic and lifelong condition.

Inclusion Criteria:

• Must consent to being a part of the study
• Must be willing and able to physically present to the our office site on the Hospital campus whenever necessary over the course of the study
• Able to read, write, speak, and understand English
• Willing to complete study surveys over the course of the study.
• Must have a diagnosis for moderate to severe OSA (AHI ≥15) with indications for PAP therapy OSA is stratified into mild (5 ≤ AHI ≤ 15), moderate (15 < AHI ≤ 30), and severe (AHI>30)
• Must have declined PAP therapy (unwillingness to use), failed PAP therapy (AHI > 15 on PAP), or are inadherent to PAP therapy (not using PAP ≥4 hours/night for ≥5 nights per week, also defined as intolerance to PAP)
• Age ≥ 18 years
• BMI ≤ 40 kg/m²
• Central/Mixed apneas contribute < 25% of AHI (Predominantly Obstructive Sleep Apnea)
• Willing to complete pre-intervention and post-intervention sleep studies
• Planning to obtain MAD or HGNS as part of clinical care

Exclusion Criteria:

• AHI > 65

  o The guidelines for HGNS usage were originally approved for an AHI upper limit of 65. We will not enroll anyone in the study with an AHI greater than 65.

• Dental conditions such as temporomandibular joint disease, periodontal disease, dental disease, insufficient dentition (edentulism) to support appliance retention, and inadequate range of motion of the jaw. Similarly, patients undergoing dental realignment (e.g., braces or retaining device) are not suitable candidates.

• Chronic nasal obstruction

• Individuals without manual dexterity to place and remove the device such as those afflicted with severe arthritis, or neuromuscular disease that affects dexterity.

• Prior intolerance to MAD

• Rapid therapy required: patients in whom rapid initiation of treatment is desirable (e.g., patients with severe symptomatic OSA, sleepiness while driving) and they declined PAP without PAP failure. PAP therapy can be initiated quickly while MAD initiation requires incremental titration of the device over weeks to months to attain optimal efficacy.

• Severe or prolonged Oxygen desaturation: patients with severe oxyhemoglobin desaturation during sleep (e.g., nadir peripheral oxygen saturation [SpO2] <70 percent), caution is warranted as oral appliance therapy may not provide optimal improvement in oxygenation.

• Alcohol or illicit substance use at least daily

• Unstable psychiatric condition

• Current use of a GLP-1 receptor agonist (e.g., Zepbound, Wegovy, Ozempic, Mounjaro) with ongoing, active weight loss at the time of enrollment, or recent dose escalation within the prior 8 weeks.