the data was completed.

Introduction:

The prevalence of overlap between Chronic Obstructive Pulmonary Disease (COPD) and Obstructive Sleep Apnea Syndrome (OSAS) is around 10%. This overlap syndrome is an important issue because is related to nocturnal desaturation and its complications. The use of portable monitoring devices (PM) for the diagnosis of OSAS was recently accepted as an alternative to full-night polysomnography (PSG). However, there are not studies evaluating the PM recording in COPD patients to detect or exclude OSAS.

Objective:

To evaluate if a PM (Stardust®, Respironics, Inc, USA) could accurately measure the apnea-hypopnea index (AHI) in COPD patients with a suspicion of OSAS.

Patients will be recruited from the Pneumology outpatient clinic of UNIFESP, Patients had been diagnosed with COPD in GOLD's stages II and III, were stable (no COPD exacerbation in the last three months), were using bronchodilators without a dose change during that period, and had symptoms suggestive of OSAS (loud snoring, reported breathing pauses during sleep and excessive sleepiness). We excluded patients with other sleep-related disorders, a diagnosis and/or previous treatment for OSAS, severe cardiovascular disorders or neuromuscular disease and those using oxygen, psychotropic drugs, alcohol or other drugs of abuse.

Patients will undergo two assessments of sleep, randomly determined: 1) PM at home for one night, 2) PM in the sleep laboratory simultaneously to the PSG. Three apnea-hypopnea index (AHI) values will be obtained and analyzed: a) AHI from PM at home, b) AHI from PM in the laboratory, and c) AHI from the PSG. Analyses of all evaluations will be performed by two trained technicians, blinded to study details.

Inclusion Criteria:

• Presence of Chronic Obstructive Pulmonary Disease stage II and III of Global Initiative for Chronic Obstructive Lung Disease, stable for three months, and with symptoms suggestive of Obstructive Sleep Apnea Syndrome.

Exclusion Criteria:

• Presence of Chronic Obstructive Pulmonary Disease stage II and III

Patients recruited from the Pneumology Clinic of UNIFESP, diagnosed with COPD stage II and III of Global Initiative for Chronic Obstructive Lung Disease, stable for three months, and with symptoms suggestive of Obstructive Sleep Apnea Syndrome.