Obstructive Sleep Apnea

Clinical Principles

Obstructive sleep apnea is an increasingly common disorder that is strongly linked to obesity.

Neurocognitive sequelae, such as daytime sleepiness and impaired executive function, are important factors in motor vehicle accidents and probably contribute to loss of work-related productivity.

Emerging clinical research studies suggest an increasing role of obstructive sleep apnea in cardiovascular disease, particularly systemic hypertension and congestive heart failure.

Continuous positive airway pressure (CPAP) is very effective at reversing sleep-related disordered breathing events and consequent daytime symptoms, although maintaining patient adherence can be challenging.

The role of CPAP and other modes of therapy in the management of systemic disease that coexists with obstructive sleep apnea is promising but remains to be determined by rigorous interventional controlled trials.

Pathophysiologic Principles

Obstructive sleep apnea is associated with a reduced-caliber upper airway, which, despite an increase in compensatory pharyngeal dilator muscle electromyographic output, is vulnerable to further narrowing or collapse.

Acute and repetitive effects of apneas and hypopneas include oxygen desaturation, reductions in intrathoracic pressure, and central nervous system arousals, all of which may contribute to the cardiovascular diseases that frequently coexist with obstructive sleep apnea.

Disruption of neural circulatory control in obstructive sleep apnea is demonstrated by heightened peripheral chemoreflex sensitivity and sympathetic overactivity during both sleep and wakefulness.

Metabolic abnormalities in obstructive sleep apnea appear to be mediated in part by insulin resistance, which may be independent of body weight, and by the dysregulation of leptin.