Mechanisms of sleep-disordered breathing: causes and consequences

Area of Science:

• Sleep Medicine
• Cardiovascular Physiology
• Respiratory Medicine

Background:

• Obstructive sleep apnea (OSA) involves upper airway collapse during sleep due to anatomical factors and reduced pharyngeal muscle activity.
• Central sleep apnea (CSA) stems from instability in respiratory control, causing inadequate breathing drive alternating with hyperventilation.

Purpose of the Study:

• To explore the complex relationship between OSA and CSA, highlighting their frequent coexistence and shared pathophysiological pathways.
• To elucidate how OSA and CSA contribute to cardiovascular disease development.

Main Methods:

• Review of existing literature on the pathophysiology of OSA and CSA.
• Analysis of the acute and chronic physiological consequences of both apnea types.
• Examination of the link between sleep apnea mechanisms and cardiovascular disease.

Main Results:

• OSA and CSA are not entirely distinct, often occurring together and influencing each other.
• Both conditions induce intermittent hypoxia, sleep arousals, and intrathoracic pressure swings.
• These effects lead to autonomic dysregulation, endothelial dysfunction, and cardiac remodeling.

Conclusions:

• The shared pathophysiological mechanisms of OSA and CSA provide a basis for their predisposition to cardiovascular diseases, including ischemic heart disease and stroke.
• Understanding the interplay between OSA and CSA is crucial for managing cardiovascular risk in affected patients.