Apnea Hypopnea Index Severity Versus Head Position During Sleep

This study evaluates the correlation of the position of the head during sleep, independent of the position of the torso, and the severity of apnea hypopneas in obstructive sleep apnea.

Obstructive Sleep Apnea (OSA) is a common diagnosis in the general population, with a prevalence in the United States of 3-7% in men and 2-5% in women. It is defined as a sleep-related breathing disorder that results in decreased or complete cessation of airflow while the patient has ongoing breathing effort. It is well documented that trunk position significantly affects the severity of OSA. In fact, 50-75% of individuals with a diagnosis of OSA show supine predominance or worsened apnea-hypopnea index (AHI) when sleeping in the supine position. Positional Obstructive Sleep Apnea (POSA) is defined as an AHI ≥5 with \>50% AHI reduction between the supine and non-supine positions and AHI. Studies show 49.5% of individuals with mild OSA (AHI 5-15), 19.4% with moderate OSA (AHI 15-30) and 6.5% in severe OSA (AHI \> 30) had POSA. Due to this high prevalence of POSA, especially in the mild and moderate OSA populations, positional therapies have been developed and researched. In this clinical trial, if only the head position is considered, all subjects are positional sensitive and OSA severity can be calculated and consistently minimized by limiting the allowable range of head roll angle during sleep. Ten subjects underwent a standard polysomnography with an additional head angle sensor and coached to fall asleep in various head positions. Torso position was changed between supine and non-supine for a given head roll angle epoch to show the OSA severity change with torso position. Each sleep epoch of unique head pitch and roll angle was scored individually for AHI and Oxygen Saturation (SPO2) de-saturation. Investigators hypothesize that specific head roll angles independent of torso position will significantly reduce AHI and SpO2 desaturation severity in patients. The primary aim is to determine the head roll angles that significantly improve POSA independent of torso position. By doing this, Investigators believe to identify a "safe zone" of head roll angles that improve POSA and that can be used to support the development of head positional therapy for POSA patients.