The overlaps of asthma or COPD with OSA: A focused review

Abstract

Asthma, chronic obstructive pulmonary disease (COPD) and obstructive sleep apnoea (OSA) are the most common respiratory disorders worldwide. Given demographic and environmental changes, prevalence for each is likely to increase. Although exact numbers are not known, based on chance alone, many people will be affected by both lower airways obstruction and concomitant upper airway obstruction during sleep. Some recent studies suggest that there is a reciprocal interaction, with chronic lung disease predisposing to OSA, and OSA worsening control and outcomes from chronic lung disease. Thus, the combination of wake and sleep respiratory disorders can create an overlap syndrome with unique pathophysiological, diagnostic and therapeutic concerns. Although much work needs to be done, given the above, Respirologists, Sleep Medicine and Primary Care providers must be vigilant for overlap syndromes. Accurate diagnosis of, for example, OSA as a cause of nocturnal symptoms in a patient with asthma is likely to limit further ineffective titration of medications for asthma. Moreover, prompt treatment of OSA in the overlap syndromes will not only offer symptomatic benefit of OSA, but also improve symptoms and healthcare resource utilization attributable to obstructive lung disease, and in COPD, it may reduce mortality.

Year in review 2017: Interstitial lung disease, pulmonary vascular disease and sleep

“…The concurrence of OSA with various neurocognitive and mental health issues can worsen outcomes compared with experiencing either condition in isolation . Similar worsening of outcomes has been reported with the overlap of OSA and obstructive lung disease (overlap syndrome) . Improved cognition function with CPAP has been reported, particularly in vulnerable populations, while its use in overlap syndrome is associated with quality of life improvements, reduced hospitalizations and lower mortality …”

“…Mounting evidence demonstrates the complex interactions between OSA and other co‐morbid conditions . These co‐morbidities affect healthcare utilization and are associated with poorer clinical outcomes .…”

Polysomnographic variables in Alternate overlap syndrome: data from sleep heart health study

“…Effects of asthma on OSA involves mechanical factors (increased airway resistance during REM sleep due to reduction in Functional Residual capacity and End Expiratory Lung Volume leading to upper airway collapse and worsening of apnea), Smoking (directly increasing airway edema and resistance), Corticosteroids use (causing airway myopathy, obesity and airway fat deposition) and increased nasal resistance due to rhinitis or polyps. Similarly, recent animal and human studies have shown OSA could influence lower airway inflammation and remodeling [22]. Effects of OSA on asthma includes increasing vagal tone during apneic episodes triggering muscarinic receptors induced bronchoconstriction, intermittent hypoxic oxidative stress causing endothelial dysfunction, increased inflammation, Vascular Endothelial Growth Factor (VEGFhypoxia-sensitive glycoprotein which may contribute to bronchial inflammation), Leptin-related airway changes (pro-inflammatory effects), Sleep fragmentation (causing increased cholinergic outflow during REM sleep), GERD (asthma triggered form microaspirations and respiratory mucosal injury and reflex bronchospasm) and cardiac dysfunction (OSA leads to cardiac dysfunction and CHF itself has been known to worsen asthma) [23][24][25][26].…”

Update in respiratory sleep disorders: Epilogue to a modern review series

“…This trend will represent an opportunity for the sleep field, for example treatment of OSA, which reduces perioperative complications, at least in some individuals . Similarly, addressing sleep disorders in congestive heart failure, diabetes, COPD and accelerated cognitive decline may serve to improve the wellbeing of these patients from the standpoint of quality of care and health outcomes …”