Review
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Exp Med. May 20, 2015; 5(2): 77-83
Published online May 20, 2015. doi: 10.5493/wjem.v5.i2.77
Obstructive sleep apnea syndrome and cardiovascular disease: The influence of C-reactive protein
Izolde Bouloukaki, Charalampos Mermigkis, Eleftherios M Kallergis, Violeta Moniaki, Eleni Mauroudi, Sophia E Schiza
Izolde Bouloukaki, Charalampos Mermigkis, Eleftherios M Kallergis, Violeta Moniaki, Eleni Mauroudi, Sophia E Schiza, Sleep Disorders Center, Department of Thoracic Medicine, University General Hospital, Medical School of the University of Crete, 71110 Heraklion, Crete, Greece
Author contributions: All authors contributed to conception and design of the study, acquisition of data, or analysis and interpretation of data, drafted the article or making critical revisions related to important intellectual content of the manuscript and approved of the final version of the article to be published.
Conflict-of-interest: The authors have no conflict of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Sophia E Schiza, MD, PhD, Assistant Professor of Respiratory Medicine, Sleep Disorders Center, Department of Thoracic Medicine, University General Hospital, Medical School of the University of Crete, Rio, 71110 Heraklion, Crete, Greece. schiza@med.uoc.gr
Telephone: +30-281-0394824 Fax: +30-281-0394670
Received: October 20, 2014
Peer-review started: October 20, 2014
First decision: November 27, 2014
Revised: March 2, 2015
Accepted: March 18, 2015
Article in press: March 20, 2015
Published online: May 20, 2015
Abstract

Obstructive sleep apnea syndrome (OSAS) is a common medical condition, associated with atherosclerosis and cardiovascular disease (CVD). The underlying pathophysiologic mechanisms of this association have not been completely understood and may be multifactorial in origin. A number of studies suggest that inflammatory processes have emerged critical in the pathogenesis of CVD in OSAS. A range of circulating inflammatory molecules has been identified and measured, with a view to assess inflammation and predict vascular damage risk, such as plasma cytokines, adhesion molecules, and C-reactive protein (CRP). CRP is a relevant marker worthy of further study, because not only is elevated in patients with OSAS, but also is rapidly becoming a risk factor for cardiac disease. Furthermore, in selected OSAS patients, aggressive treatment of the disorder may lead to retarding or even improvement of CVD progression. However, still there is a debate on the true correlation between CRP and OSAS, as well as the clinical effect of any reduction after OSAS treatment. Further research is required to define those OSAS patients who will have a considerable reduction with treatment, as well as to understand the significance of the interaction between cardiovascular risk factor and CRP reduction in patients with OSAS.

Keywords: Sleep apnea, Cardiovascular, C-reactive protein

Core tip: Obstructive sleep apnea syndrome (OSAS) is a common medical condition, associated with atherosclerosis and cardiovascular disease (CVD). A number of studies suggest that inflammatory processes have emerged critical in the pathogenesis of CVD in OSAS. C-reactive protein (CRP) has been the most studied inflammatory protein to date and a frequently used marker to predict the occurrence of CVDs. Unfortunately, the question still remains if CRP is truly related to OSAS, as well as the clinical effect of any reduction after treatment of OSAS.