['Reduced arterial elasticity is an important mediator of accelerated atherogenesis and consequent increased cardiovascular morbidity in obstructive sleep apnea (OSA). The aim of our study was to investigate whether continuous positive airway pressure (CPAP) therapy may improve arterial elasticity in subjects with OSA.', 'In 44 subjects with OSA, we measured arterial elasticity by applanation tonometry before and after 6 months of treatment with CPAP. Nine OSA+ subjects withdrew from the study.', 'The 35 patients with OSA who completed the 6-month CPAP treatment showed a marked reduction in both the large artery (LAEI, P=0.001) and small artery (SAEI, P=0.009) elasticity indices, independent of potential confounders. In OSA+ subjects who withdrew from the study, SAEI and LAEI did not change significantly over time.'] Does continuous positive airway pressure therapy improve arterial elasticity in patients with obstructive sleep apnea?