REVIEWS  SLEEP DISORDERS 

Minerva Pneumologica 2009 December;48(4):295-306

Copyright © 2009 EDIZIONI MINERVA MEDICA

language: English

Chronic obstructive pulmonary disease with concomitant obstructive sleep apnea: physiological, clinical and therapeutic implications

Zamarron C. ¹, Del Campo Matias F. ²

¹ Service of Pneumology, University Clinic Hospital, Santiago, Spain 2 Rio Hortega University Hospital, Valladolid, Spain

Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are highly prevalent in Western societies. However, OSAS frequently remains unrecognized and untreated among patients with COPD. The coexistence of these disorders is known as overlap syndrome and is more the result of chance than of a pathophysiological link. Although there have been some reports of very high incidence of OSAS among COPD patients, recent studies indicate that this incidence is similar to the general population. Overlap patients are older and less obese than patients with OSAS only. During sleep, overlap patients present significant nocturnal desaturations associated to changes in upper airway resistance, ventilatory response and breathing control. Individuals with overlap syndrome are at greater risk for pulmonary hypertension, right heart failure, and hypercapnia than patients who have either COPD or OSAS alone. Of the frequent complex chronic comorbidities associated with COPD, OSAS participates in the development of local and systemic inflammation as well as cardiovascular morbility. Clinical assessment of COPD should take sleep complaints into consideration. Nocturnal polysom-nographic monitoring in COPD is usually performed when coexistence of OSAS is suspected. In stable patients with overlap syndrome and hypoxia, supplemental oxygen with CPAP is the most widely used treatment. The aim of the present review was to analyze the pathophysiology, epidemiology and clinical features as well as therapy for overlap syndrome.