Role of pro-/anti-inflammatory cytokines and their correlation with established risk factors in South Indians with coronary artery disease.

Cytokines are responsible for the modulation of immunological and inflammatory processes and play a significant role in the pathogenesis of coronary artery disease. We estimated the levels of pro-/anti-inflammatory cytokines in South Indian patients with coronary artery disease. The study population comprised of groups 1-3: 100 patients each with acute myocardial infarction, unstable angina, and stable angina, respectively, and group 4 (100 healthy controls). Cytokine levels (interleukin-6, interleukin-8, interleukin-10, and tumor necrosis factor-alpha) were estimated by enzyme-linked immunosorbent assay (ELISA). Interleukin-6, interleukin-8, and tumor necrosis factor-alpha levels were significantly higher in patients from groups 1 and 2, than in group 3 and controls. Acute myocardial infarction patients exhibited higher serum levels of interleukin-10 compared with other groups and control subjects. Patients with unstable angina had significantly lower interleukin-10 concentrations than those with stable angina. The ratios of pro-/anti-inflammatory cytokines in all the study groups increased significantly when patients with unstable angina were compared to other groups. In patients with acute myocardial infarction, interleukin-10 and tumor necrosis factor-alpha levels showed significant correlation with established risk factors such as body mass index, blood pressure, and lipid levels. Acute myocardial infarction patients show elevation in proinflammatory and anti-inflammatory cytokines, while unstable angina is associated with low levels of serum interleukin-10. Higher levels of anti-inflammatory cytokine interleukin-10 may be needed to provide protection in unstable angina. These cytokines are markers of coronary artery disease and may be used for the identification of high-risk patients with unstable angina/acute myocardial infarction.