as nonrestorative sleep and excessive daytime sleepiness (EDS). 7,8In addition to EDS, OSA is associated with reduced quality of life, poor cognitive function, and road traffic accidents, independent of age or sex. 9 -11 The principal morbidity and mortality of the condition, however, are due to the increased risk of the development and progression of numerous CVDs. 4 A large body of evidence has accumulated to date strengthening the association between OSA and CVD, with increased risk persisting after correction for common cardiovascular risk factors. 12 Obstructive sleep apnea is associated with increased incidence of systemic arterial hypertension, coronary artery disease, congestive cardiac failure, and stroke, 4,13,14 and although Introduction Obstructive sleep apnea (OSA) is a growing public health problem. 1 The prevalence of the disorder has been increasing rapidly over the last 2 decades in line with the obesity epidemic in the developed world. 2-4 It is estimated that OSA affects nearly 1 billion people worldwide. However, a significant proportion of patients remain undiagnosed, 5 with one estimate suggesting that more than 30 million people are undiagnosed in Europe alone. 1 There is a male to female predominance of 2 to 1, and OSA is more common in the middle -aged and elderly population. 6 Obstructive sleep apnea is characterized by recurrent partial or complete upper airway collapse during sleep leading to intermittent hypoxia (IH) and recurrent arousals culminating in disrupted sleep quality that typically manifests