Serial changes in plasma levels of cytokines in patients with coronary artery disease

Abstract

Objectives: Inflammation is known to be a major determinant of the progression of coronary artery disease (CAD). In the present study we have evaluated the plasma levels of cytokines-tumor necrosis factor-alpha (TNF), interleukin- 1 alpha (IL-1), interleukin-6 (IL-6), interferon-gamma (IFN), and interleukin-10 (IL-10)- to examine the association between these cytokines and C-reactive protein (CRP) in patients with CAD.

Methods: Patients with acute coronary syndromes (ACS; n = 20) were compared with patients with stable angina (SA; n= 20) and with control volunteers (C; n= 20). Blood samples were collected at the time of admission from all patients and 15 and 30 days thereafter.

Results: CRP levels (20.8+/-8.8 mg/L) (mean+/-SEM) were higher at baseline in ACS than SA patients (4.1+/-0.8mg/L) or the control subjects (5.1+/-1.8mg/L) (p<0.05). At admission, IL-6 was detected in 50% of the ACS patients and 5% of the SA patients or control subjects, while TNF was detected in 35% of the ACS and SA patients but only in 5% of control subjects. Subsequently, IL-6 levels declined and were no longer detectable, while TNF levels increased among ACS patients at all time periods tested when compared with other patients. The presence of IL-1 and IL-10 were not detectable in the blood samples examined, and IFN could only be detected in the ACS group. A significant correlation was observed between IL-6 and CRP levels (r=0.4; p<0.01) in all groups. There were no correlations among any of the other cytokines and CRP levels.

Conclusions: Our study demonstrates raised levels of TNF, IL-6, IFN, and CRP in patients with ACS and a positive correlation between IL-6 and CRP but not with the other cytokines.

Figure 1

Distribution of rates' frequency of cytokines detection on admission (baseline, a), at 15 days (b), and at 30 days (c) in patients with ACS, SA, and in individuals without cardiovascular disease (Control). Abbreviations: ACS, acute coronary syndromes; IFN, interferon; IL-6, interleukin-6; SA, stable angina; TNF, tumor necrosis factor-α.