Obstructive sleep apnea and hypertension: a critical review.

Obstructive sleep apnea (OSA) is a prevalent sleep disorder which is characterized by recurrent upper closure with oxygen desaturation and sleep disruption. OSA increases the risk of vascular disorders in the form of stroke, myocardial infarction, congestive heart failure, and hypertension. The mechanisms underlying the vascular disorders are several and include intermittent hypoxia with release of cytokines, angiogenic inhibitors, free radicals, and adhesion molecules. During apneas, arterial blood pressure gradually rises and surges abruptly after the termination of apnea. Two thirds of patients with OSA will ultimately have diurnal hypertension. This review discusses the literature supporting the significant role of OSA in hypertension and the effect of OSA treatment on blood pressure.