IJCS | Volume 31, Nº5, September / October 2018

DOI: 10.5935/2359-4802.20180038 532 REVIEW ARTICLE International Journal of Cardiovascular Sciences. 2018;31(5)532-537 Mailing Address: Luiz Fernando Moreira Izidoro Avenida Pará, 1.720, Umuarama. Postal Code: 38400-902. Uberlândia, MG - Brazil. E-mail: luiz.izidoro@ufu.br, moreiraizidoro@hotmail.com Neutrophil-Lymphocyte Ratio in Cardiovascular Disease Risk Assessment Heitor Oliveira Santos and Luiz Fernando Moreira Izidoro Universidade Federal de Uberlândia, Uberlândia, MG - Brazil Manuscript received August 21, 2017, revised manuscript December 18, 2017, accepted February 16, 2018. Cardiovascular Diseases / physiopathology; Bi oma rke r s ; Neut roph i l s ; Leukocy t e Count ; Atherosclerosis / physiopathology; Inflammation. Keywords Abstract The development of cardiovascular diseases with atherosclerotic origin is associated with a severe inflammatory process. Neutrophils and lymphocytes are cells sensitive to this type of disorder and their ratio, known as the NLR (neutrophil/lymphocyte ratio), has shown to be useful in clinical practice. The aim of this study was to assess the role of NLR in cardiovascular disease risk assessment. We carried out a literature review in the PubMed databases searching for articles published between 2001 to 2017 and found that NLR is in fact a useful marker for cardiovascular disease. Using NLR in patients at cardiovascular risk would be useful to delineate the prognosis of patients with this disease pattern. Introduction Among the diseases that affect humans, those related to the cardiovascular systemwarrant great prominence. 1,2 Currently, these diseases account for more than 17million deaths worldwide each year, and the estimate for 2030 is that this figure will reach 23.6 million, with acute myocardial infarction being the most common cause of these deaths. 3,4 Very often, this cardiac event is associated with the appearance of atheromaplaques lodged in the intima layers of the coronary arteries, triggering inflammatoryprocesses. This risk factor may be diagnosed by the concentration/ amount of inflammatory markers found in the peripheral blood, such as neutrophils and lymphocytes. 4,5 Considering the potential of these different cell types, i.e., neutrophils and lymphocytes, in the genesis and evolution of atheroma plaques, the neutrophil/ lymphocyte ratio (NLR) has a high diagnostic potential for cardiovascular diseases. Neutrophil and lymphocyte analyses are simple, relatively inexpensive, and widely available. 6 Therefore, this review aimed to discuss the importance of NLR and its inclusion in the list of useful tools for the diagnosis/prognosis of atheroma-related heart disease. Atherogenesis and the Neutrophil/Lymphocyte Ratio As shown in figure 1, endothelial dysfunctions related to atherosclerotic plaques are usually associated with states of neutrophilia, together with lymphopenia processes. The antagonism between inducing and protective factors of inflammatory processes favors the onset of injuries in the vascular endothelium, as well as the onset of atherosclerosis. The body is exposed to systemic stress in the immunological lack of control due to the inflammatory process related to cardiovascular diseases, increasing the levels of cortisol and catecholamines, so that the lymphocytes are affected by this imbalance, weakening its role in modulating the inflammatory response. 7-9 Infarcted patients have elevated cortisol levels. This increase induces the reduction of lymphocytes by apoptosis, and CD4+ and CD8 cells become more sensitive to tumor necrosis factor-alpha (TNF- α ). 10 This is one of the most likely mechanisms to explain lymphopenia developed during cardiovascular disease evolution. However, the pathophysiological mechanism of this decrease has not yet been fully elucidated. 9 On the other hand, mechanisms related to neutrophilia in cardiovascular diseases are more clarified,