['Computed tomography (CT) is used to study coronary artery plaques, but little is known about its potential to characterize plaque composition. This study assesses the relation between carotid calcium score (CCS) by CT and plaque composition, namely extracellular matrix, inflammatory mediators, and calcium metabolites.', 'Thirty patients with significant carotid stenosis underwent preoperative CT. CCS was quantified by Agaston calcium score. Plaque components were studied histologically and biochemically (collagen, elastin, and glycosaminoglycans). Fraktalkine, interferon-γ, interleukin-10, interleukin-12 p70, interleukin-1β, interleukin-6, monocyte chemoattractant protein-1, platelet-derived growth factor-AB/BB, RANTES and tumor necrosis factor-α, and parathyroid hormone were measured using Luminex technology.', 'Plaques with CCS ≥400 had more calcium (P=0.012), less glycosaminoglycan (P=0.002), tumor necrosis factor-α (P=0.013), and parathyroid hormone (P=0.028) than those with CCS <400. CCS correlated with plaque content of calcium (r=0.62; P<0.001) and inversely with glycosaminoglycan (r=-0.49; P=0.006) and tumor necrosis factor-α (r=-0.56; P=0.001).'] Is low carotid calcium score associated with higher levels of glycosaminoglycans , tumor necrosis factor-alpha , and parathyroid hormone in human carotid plaques?