Estudo comparativo do perfil lipídico e de marcadores inflamatórios em pacientes com angina estável e síndrome coronariana aguda

Abstract

Introduction: Inflammation plays an important role in all stages of coronary atherosclerotic disease (CAD), including in its acute clinical manifestations. Cardiovascular risk factors contribute to the initiation of atherosclerosis and promote the development of cardiovascular disease. Endothelial and immune system cells release cytokines, chemokines, vasoactive molecules and growth factors which promote a low-grade inflammatory state. Pro-inflammatory cytokines increase serum levels of acute phase proteins, such as C reactive protein (CRP). Circulating plasma levels of many inflammatory molecules have been used as markers for coronary artery disease (CAD). The purpose of the present study was to assess the serum concentrations of interleukins 6, 8, 10 (IL-6, IL-8, IL-10), vascular cell adhesion molecule -1 (VCAM-1) and CRP in patients with acute coronary syndrome (ACS) as compared to stable angina patients. Risk factors for CAD were also analyzed. Methods: A total of 45 patients were studied. Eleven had ACS and 34 had chronic stable angina with CAD documented by coronary angiography. Fasting blood samples were obtained before coronary angiography. Interleukins and VCAM-1 were measured by ELISA and CRP by nephelometry. The lipid profile was assessed by measuring the serum levels of total cholesterol, HDL, VLDL, LDL, triglycerides, apolipoproteins B and A-1. The clinical and laboratory variables were compared between the two groups by univariate (t test or chi-squared / Fishers exact test) and multivariate analyses (multiple logistic regression). Results: The univariate analysis showed that the two groups were similar regarding the demographic characteristics and the risk factors for CAD, except for smoking, lower levels of HDL and apolipoprotein A1 and higher levels of triglycerides and VLDL, which were more prevalent in the ACS group. IL-8 (p = 0.002) was significantly higher in the ACS group. There were no differences in the other markers of inflammation between the two groups. After multivariate adjustment, IL-8 and VLDL remained statistically significant. Conclusion: IL-8 concentrations were significantly higher in patients with ACS compared to patients with stable angina, suggesting that IL-8 may play a role in plaque instability. IL-8 assessment has the potential to assist in the diagnosis of ACS and the inhibition of this cytokine may lead to new methods of treatment for unstable forms of CAD.