Circulating markers of inflammation are related to carotid artery atherosclerosis

The role of inflammation in atherothrombotic disorders is becoming increasingly recognized. The present study prospectively investigates relationships between inflammatory markers and hemostatic variables, and non-invasive measures of carotid artery atherosclerosis.

Markers of hemostasis (sP-selectin and fibrinogen), cytokines (IL-6, IL-8, TNF-a and MCP-1), inflammatory variables (hsCRP, SAA and calprotectin) and cell adhesion molecules (ICAM-1 and VCAM-1) as well as ultrasonography of the carotid arteries were assessed in 111 consecutive outpatients with manifest or suspected coronary artery disease (CAD).

Thirty-eight patients with manifest cardiovascular disease had higher IL-6 (P < 0.01) but not hsCRP levels. Higher levels of IL-6, calprotectin and VCAM-1 (all P < 0.05) were found in 35 patients with carotid plaques. In the whole study population (n = 109) an increased common carotid artery lumen diameter (LD) and cross sectional intima-media area (CIMA) was related to higher IL-6, IL-8 and MCP-1 levels (all P < 0.05), and increased LD also to higher hsCRP, calprotectin (both P < 0.05), sP-selectin and fibrinogen levels (both P < 0.01). Both LD and CIMA were related to VCAM-1 (both P < 0.01), but not to ICAM-1 levels. The intima-media thickness of the carotid artery was only positively related to MCP-1 levels (P < 0.05). Only the relation between IL-6 and LD remained significant after adjustment for age, gender, body mass index, smoking status or present lipid-lowering treatment.

Several biomarkers of inflammation are related to ultrasonographic measures of carotid artery atherosclerosis in patients with moderate to high prevalence of CAD. IL-6 seems to be an independent and useful biomarker of atherosclerosis in this group of patients.