Background Cardiovascular disease is the commonest cause of morbidity and mortality in chronic dialysis patients [1]. Sleep studies in ESRD patients have identified increased prevalence of sleep apnea (SA), both obstructive (OSA) and central (CSA) in origin [2]. The reported prevalence of SA in patients with ESRD ranges from 50% to 70% [3], which is dramatically higher than the estimated prevalence of 2% to 4% in the general population [4]. SA has been recognized as a novel risk factor for cardiovascular disease in general population [5]. Recent evidence showed that severity of SA in hemodialysis patients is associated with severity of coronary artery calcifications [6]. Underlying mechanisms by which SA adversely affects cardiovascular morbidity and mortality have not been fully established yet. The presence of untreated SA may further impair fluid balance, cardiovascular function and increase mortality through abnormal vagal or sympatomimetic responces and hypoxia [7]. One intriguing possibility is oxidative stress, which has been implicated in cardiovascular disease in patients with ESRD [8]. Recent study demonstrated association between SA and decreased antioxidant status in hemodialysis patients [6]. Repeated apnea-related hypoxic events in patients with SA may trigger elevated oxidative stress [9].