Effects of continuous positive airway pressure on arterial stiffness and oxidative stress in patients with obstructive sleep apnoea

Backround: Obstructive sleep apnoea (OSA) is associated with increased arterial stiffness and endothelial dysfunction. OSA-related oxidative stress, systemic inflammation and endotoxemia may play a role in vascular derangements. Aims: We investigated effects of continuous positive airway pressure (CPAP) therapy on arterial stiffness, body composition, endotoxemia and oxidative stress. Methods: 40 subjects with OSA [age (mean±SD) 50±8 years, body mass index (BMI) 31.9±4.5 kg/m 2 ] free of cardiovascular diseases except for arterial hypertension were enrolled. Arterial stiffness was assessed by carotid-radial pulse wave velocity (PWV) (Complior®, France), body composition by measuring bioelectrical impedance (Bodystat 1500, UK). PWV, body composition, serum lipopolysaccharides-binding protein (LBP) and oxidized low-density lipoprotein (oxLDL), were measured at baseline and after 3 months of CPAP. Results: Compliance with CPAP was 4.1±1.8 hours/night. Reductions of PWV in association with reductions in oxLDL were observed after 3 months of CPAP (9.7±1.6 to 9.0±1.6 m/s, p=0.003; 501±186 to 381±174 ng/ml, p=0.002, respectively). Improvements in arterial stiffness were observed regardless body weight or body composition change. CPAP had no effect on an endotoxemia marker (serum LBP). Conclusions: Our results suggest that in patients with OSA without overt cardiovascular diseases, elimination of OSA by CPAP results in improvements in arterial stiffness in association with reductions in oxidative stress. Support: APVV-0134-11, VEGA 1/0863/15 and 1/0208/16, Ministry of Education, Slovakia.