Background: This study was designed to determine if serum cystatin C (Cys C) levels are affected by metabolic syndome and whether they correlate with lipid peroxidation and total antioxidant status (TAS) in this disorder.
Material and Method: Cases with metabolic syndrome diagnosed according to the ATP III criteria (18 females, 12 males) were compared with healthy control subjects (20 females, 17 males) matched by age and gender. Plasma Cys C, malondialdehyde (MDA), and TAS levels were studied.
Results: Compared with the controls, Cys C and MDA levels were significantly higher (p<0.001 and p<0.001, respectively), whereas TAS was lower (p<0.001) in metabolic syndrome patients. A significant positive correlation between MDA and Cys C (r=0.308, p<0.05) and a significant negative correlation between TAS and Cys C levels (r=-0.358, p<0.01) were found.
Conclusions: As Cys C and MDA levels increased but TAS decreased, Cys C may be an important indicator in the pathogenesis of metabolic syndrome.

Keywords: Malondialdehyde - blood, Lipid Peroxidation, cystatin C, Cystatins - blood, Case-Control Studies, Metabolic Syndrome X - blood, Biological Markers - blood, Antioxidants - metabolism, Adult