Elevated Levels of C-Reactive Protein and Interleukin-6 in Patients With Obstructive Sleep Apnea Syndrome Are Decreased by Nasal Continuous Positive Airway Pressure

Abstract

Background-C-reactive protein (CRP) and interleukin (IL)-6 are important risk factors for atherosclerosis and coronary heart disease. In the present study, we examined serum levels of CRP and IL-6, IL-6 production by monocytes, and the effect of nasal continuous positive airway pressure (nCPAP) in patients with obstructive sleep apnea syndrome (OSAS). Methods and Results-After polysomnography, venous blood was collected at 5 AM from 30 patients with OSAS and 14 obese control subjects. Serum levels of CRP and IL-6 and spontaneous production of IL-6 by monocytes were investigated. In addition, the effects of 1 month of nCPAP were studied in patients with moderate to severe OSAS. Levels of CRP and IL-6 were significantly higher in patients with OSAS than in obese control subjects (CRP PϽ0.001, IL-6 PϽ0.05). IL-6 production by monocytes was also higher in patients with OSAS than in obese control subjects (PϽ0.01). In patients with OSAS, the primary factors influencing levels of CRP were severity of OSAS and body mass index and those influencing levels of IL-6 were body mass index and nocturnal hypoxia. nCPAP significantly decreased levels of both CRP (PϽ0.0001) and IL-6 (PϽ0.001) and spontaneous IL-6 production by monocytes (PϽ0.01). Conclusions-Levels of CRP and IL-6 and spontaneous production of IL-6 by monocytes are elevated in patients with OSAS but are decreased by nCPAP. Therefore, OSAS is associated with increased risks for cardiovascular morbidity and mortality, and nCPAP may be useful for decreasing these risks.

Independent Association Between Obstructive Sleep Apnea and Noncalcified Coronary Plaque Demonstrated by Noninvasive Coronary Computed Tomography Angiography

“…Identification of these plaques with increased frequency on MDCT scans in patients with OSA is especially relevant, as prevalence of OSA is high in patients with ACS. 24 We also found that patients with OSA have significantly higher severity of stenosis and have significantly greater number of vessels involved as compared with the non-OSA group (P < 0.05).…”

Increased arterial stiffness in obstructive sleep apnea: a systematic review

“…72 Various studies have also found that C-reactive protein, tumor necrosis factor-a, interleukin-6 (IL-6), IL-8 and cell adhesion molecules such as intercellular adhesion molecule-1 are increased in the circulation in OSA patients independent of obesity. 10,15,73,74 Increased inflammation may have a role in the pathogenesis of OSA, increasing arterial stiffness and contributing to the early atherosclerosis found in OSA patients. 3 Furthermore, it also appears that endothelial dysfunction in OSA is partially mediated through apoptotic dysregulation; circulating apoptotic endothelial cells were found to be associated with AHI (r¼0.56, P¼0.004).…”

“…8 Although OSA patients commonly demonstrate one or more established cardiovascular risk factors, there is now a considerable body of evidence indicating that OSA itself is an independent cardiovascular risk factor. 3,[9][10][11][12][13][14][15][16] Arterial stiffness determines how quickly the pulse wave generated by the contracting heart travels to the periphery and is reflected back. The larger arteries of the cardiovascular system are critical in the conduction of blood flow to the periphery.…”

Effects of long-term treatment for obstructive sleep apnea on pulse wave velocity

“…1,2 Atherosclerosis is a progressive disease that is also a pivotal risk factor for these cardiovascular disorders. OSA induces systemic HT, inflammation, 3 endothelial dysfunction 4 and disturbances in sympathetic activity, 5 all of which are known to accelerate the development of atherosclerosis. It has been shown that continuous positive airway pressure (CPAP) treatment improves these risk factors for atherosclerosis.…”