SLEEP ON Your SIDE (SOS) Study

Comparison of the NightBalance Sleep Position Trainer (SPT) to Positive Airway Pressure (PAP) for the Treatment of Positional Obstructive Sleep Apnea (POSA). Primary Objective: Efficacy and Adherence of the SPT over 3 months of use compared to PAP for the treatment of POSA. The study is run from centers in France, the UK and Germany.

Participants are randomly allocated to receive one of two treatments, either Automatic Positive Airway Pressure (APAP) or NightBalance Sleep Position Therapy for a three month period. Participants are sent home with instructions to use that device nightly at home for three months. After three months of using the first device, they return to the doctor for assessment of the efficacy of the device using a sleep test and the compliance read from the device. Upon conclusion of the first three month treatment period, patients receive the alternative treatment for a further three months. At the end of the second three month period, participants return to their doctor again to assess the efficacy of the last device and read the compliance. Before any treatment and after each treatment, patients undergo a sleep test and complete some questionnaires. During each treatment period, patients complete a healthcare utilization diary and report any problems.

Eligibility Criteria:
Inclusion Criteria:

1. Subject is adult
2. Either: Treatment naïve, or PAP non-complier (defined as current AAP user with \<3 hours per night in the last 3 months per compliance download), and willing to use the APAP device per protocol
3. Diagnosis of POSA meeting all the following criteria per control PSG within 6 months of screening: AHI of \>15 during PSG with symptoms of sleepiness per Investigator discretion, or AHI of \>15 during respiratory polygraphy with comorbidities (e.g. atrial fibrillation, resistant hypertension, etc.)
4. Supine AHI at least twice the lateral AHI
5. Lateral AHI \<10
6. Supine time \>30% and \<70%
7. Understands the study protocol and is willing and able to comply with study requirements and sign informed consent. APAP non-compliant subjects must be willing to use their APAP device per protocol.

Exclusion Criteria:

1. Prior or current therapy or treatment for OSA (for Treatment naïve group); Greater than an average of 3 hours per night of APAP use (in the APAP non-complier group)
2. A female of child-bearing potential that is pregnant or intends to become pregnant
3. Any unstable or severe medical condition of any organ system that at the discretion of the site Principal Investigator (PI) might affect the patient's participation in the study or generalization of treatment results
4. Taking medication that at the discretion of the site Principal Investigator (PI) might affect the patient's participation in the study or generalization of treatment results
5. Oxygen use
6. The presence of any other sleep disorder (central sleep apnea (CSA \>5), periodic limb movement disorder (PLMAI \>15), clinical diagnosis of insomnia or narcolepsy)
7. Excessive alcohol consumption (\>21 drinks/week)
8. The use of any illegal drug(s), per subject report
9. Night or rotating shift work
10. Severe claustrophobia
11. Shoulder, neck, or back complaints that restrict sleeping position
12. Subject requires use of more than 2 pillows under the head while sleeping or sleeps in a bed/chair with raised upper body position