Sleep disordered breathing: OSA-COPD overlap

ABSTRACT

Introduction

Sleep has important effects on breathing and gas exchange that may have negative consequences in patients with chronic obstructive pulmonary disease (COPD). COPD and obstructive sleep apnea (OSA) are highly prevalent and may coexist, which is referred to as the overlap syndrome.

Areas covered

The probability of OSA-COPD overlap represents the balance of protective and promoting factors such as hyperinflation and fluid retention; thus, different clinical COPD phenotypes influence the likelihood of comorbid OSA. The clinical presentation of OSA-COPD overlap is nonspecific, and the diagnosis requires clinical awareness to identify patients needing overnight studies. Both COPD and OSA are associated with a range of overlapping physiological and biological disturbances including hypoxia and inflammation that contribute to cardiovascular comorbidities. The management of OSA-COPD overlap patients differs from those with COPD alone and the survival of overlap patients treated with positive airway pressure (PAP) is superior to those untreated.

Expert opinion

The recognition of OSA-COPD overlap has important clinical relevance because of its impact on outcomes and management. Management of the overlap should address both sleep quality and disordered gas exchange. PAP therapy has demonstrated reductions in COPD exacerbations, hospitalizations, healthcare costs and mortality in overlap patients.

KEYWORDS:

• Sleep disordered breathing
• obstructive sleep apnea
• chronic obstructive pulmonary disease
• overlap
• comorbidities
• positive airway pressure
• outcomes

Article highlights

• Sleep has important effects on breathing and gas exchange that may exacerbate the dysfunction seen while awake in COPD patients.

• Sleep disturbances in COPD are predictive of exacerbations, respiratory-related emergency utilization and all-cause mortality.

• COPD and OSA are both highly prevalent, thus the coexistence of both disorders, referred to as the overlap syndrome, may occur based on chance alone.

• There is considerable evidence of important interactions between both disorders that influence epidemiology, clinical manifestations, comorbidities, and management.

• Both COPD and OSA generate local and systemic inflammatory responses that may lead to cardiovascular morbidity and thus, the overlap syndrome should be associated with an increased likelihood of cardiovascular disease compared with either disorder alone.

• Overlap syndrome is associated with increased mortality compared to either disease alone.

• CPAP therapy is associated with reduced COPD exacerbations, COPD-related hospitalizations, healthcare costs and mortality in OSA-COPD overlap patients.

List of abbreviations

Table

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.