IL6 and endothelial dysfunction: A RCT showed that CPAP treatment reverses markers of atherosclerosis, decreases carotid intima-media thickness, pulse-wave velocity, C-reactive protein, and catecholamines after 4 months80. It is also shown a reduction in tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6)81. Withdrawal of CPAP treatment exacerbates endothelial dysfunction in patients with minimally symptomatic OSA82,83.