The purpose of this protocol is to improve the current FDA-approved continuous positive pressure auto-titration algorithm, including treatment precision, residual disease detection characteristics and phenotyping with the DeVilbiss brand AutoAdjust CPAP device.

Inclusion Criteria:

• Apnea hypopnea index ≥ 15 / hour of sleep on the diagnostic polysomnogram, or diagnostic component of a split night polysomnogram
• Sleep efficiency reported on CPAP titration night PSG should be > 78%
• Diagnosis of moderate to severe obstructive sleep apnea (AHI ≥15) or central/complex sleep apnea
• On stable CPAP or APAP [Automatic Positive Airway Pressure] therapy, with compliant use averaging 4 or more hours nightly
• Age 21-75 years
• Predominately central sleep apnea for up to 10 subjects only
• Willingness to give written informed consent and ability to adhere to visit schedule

Exclusion Criteria:

Diagnosis of mild sleep apnea

• CPAP naïve patients
• Co-morbid conditions which render participation to be at risk. These may include patients with congestive heart failure, COPD [Chronic Obstructive Pulmonary Disease] or psychiatric illness
• Allergies to mask materials
• Evidence of another primary sleep disorder
• Evidence of arousing periodic limb movements during titration
• Contraindications as listed on product labeling
• Pregnant
• Currently diagnosed with depression if symptomatic
• Deemed medically unsuitable by investigator
• Evidence of any type of infection or treatment of an infectious condition during the period of research participation
• Have a bi-level requirement, or prescribed a bi-level therapy device
• CPAP pressure >15cmH2O
• Subjects with tracheotomy
• Uncontrolled hypertension
• Require supplemental oxygen
• Stimulants, major tranquillizers or antipsychotics
• Restless Leg Syndrome or Periodic Leg Movement Index of > 5 per hour

Subjects completing the study with evaluable results

Adverse events were assessed for the period from patient's enrollment in the study up to termination (the morning following the one-night sleep study).

Adverse events were assessed per a list of probable events associated with use of CPAP equipment. There were no adverse events for the analysis population.