Introduction The portable monitoring system (PMS) recording of cardiopulmonary parameters (level III of ASDA) has been validated in subjects with high probability of Obstructive Sleep Apnea (OSA) without comorbidities.

However, there is not any study evaluating this system when OSA is associated with morbid obesity, so the validation of PMS will be very useful in order to properly work-up this highly risk population.

Objective:

To evaluate the accuracy of level III type of PMS - Stardust™" (STD), on patients with level II and III of obesity and high clinical suspicion of OSA.

Methods:Participants with BMI > 35 kg/m2 and with suspicion of OSA will consecutively be selected from an Outpatients Sleep Clinic of UNIFESP. They will be randomized for the following order of recordings:

1) STD at home for 1 night 2) STD in the sleep lab simultaneous to PSG. AHI will be taken for subsequent analysis:a) AHI PSG b) AHI STD -lab and c) AHI STD- home.

Inclusion Criteria:

• BMI > 35
• Complaints of snoring, sleep apnea, daytime sleepiness

Exclusion Criteria:

• use of home oxygen
• other sleep diseases
• inability to perform PSG

Adults BMI > 35 Male and female