Impact of overlap syndrome on severity of acute exacerbation of chronic obstructive pulmonary disease.

Background: The severity of exacerbation in chronic obstructive pulmonary disease (COPD) due to the overlap of obstructive sleep apnea syndrome (OSAS) is not known.

Aims: To find out the 1) severity of acute exacerbation of COPD (AECOPD) in patients with overlap syndrome compared to only COPD, 2) prevalence of overlap syndrome in AECOPD, and 3) clinical characteristics of COPD compared to overlap syndrome.

Materials And Methods: Fifty-one patients admitted with AECOPD were classified into; Mild exacerbation: Normal arterial blood gases (ABG) treated with antibiotics, Moderate: Normal ABG treated with parenteral corticosteroids, Severe: Type 1 respiratory failure, Very severe: Type 2 respiratory failure with normal pH and Life-threatening: Type 2 respiratory failure with pH <7.