High serum S100A8/A9 levels and high cardiovascular complication rate in type 2 diabetics with ultrasonographic low carotid plaque density

Aims S100A8/A9 complex is an inflammation-associated biomarker, which binds toll-like receptor 4 and was associated with the receptor for advanced glycation end-products. S100A8 and S100A9 were accumulated in atherosclerotic lesions. High serum levels of S100A8/A9 are associated with acute coronary syndrome and atherosclerosis in type 2 diabetes mellitus (T2DM). However, association between serum S100A8/A9 levels and vulnerable plaque remains unclear. The present study investigated the relation between serum S100A8/A9 levels and relative plaque density (RPD) of the carotid artery determined by ultrasonography in T2DM. Methods The study subjects were 72 consecutive T2DM outpatients (males/females = 42/30), who underwent the carotid artery ultrasonography. RPD in the carotid artery was calculated by the formula; RPD = [density of the carotid plaque/density of vessel lumen]. Serum levels of adiponectin and S100A8/A9 were measured. Results The median RPD was 2.1. Patients with low RPD (≤2.1) were significantly more likely to have metabolic syndrome, nephropathy, coronary artery disease, and peripheral artery disease, and higher levels of S100A8/A9, S100A8/A9-to-adiponectin ratio, and uric acid, compared to those with high RPD (>2.1). Conclusions T2DM patients with low RPD had higher prevalence of metabolic syndrome, cardiovascular diseases and higher serum S100A8/A9 levels, compared to those with high RPD.