BACKGROUND
Serum cystatin C has been reported as a better marker than serum creatinine for estimation of kidney function and may be associated with cardiovascular disease. The aim of this study was to elucidate the association of serum cystatin C with metabolic syndrome (MS), a constellation of cardiovascular risk factors, and its related components and the usefulness of serum cystatin C for the cardiovascular risk assessment. METHODS: 1,468 healthy subjects (814 men and 655 women), who visited health promotion center of Pusan National University Hospital for routine medical checkup were included. MS was defined by modified, revised National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III criteria. RESULTS: Mean serum cystatin C value was 0.87 +/- 0.17 mg/L. In partial correlation analysis adjusted by age, sex and Glomerular Filtration Rate (GFR), cystatin C was associated with most of metabolic parameters and especially had significant positive correlation with waist circumference (r = 0.215), triglyceride (TG) (r = 0.141), diastolic blood pressure (BP) (r = 0.116), and correlated negatively with high density lipoprotein (HDL) cholesterol (r = -0.152) (all P < 0.001). There were increasing trends of prevalence of MS with the increase of quartiles of cystatin C and as the number of MS components increased, cystatin C values significantly increased. Serum cystatin C was also significantly increased in MS (0.90 +/- 0.19 mg/L vs. 0.86 +/- 0.16 mg/L). In stepwise multiple regression analysis including the components of MS, Waist circumference, diastolic BP, triglyceride, and HDL cholesterol were independent determinants of serum cystatin C, but with creatinine, only waist circumference was independent determinant. CONCLUSIONS: Serum cystatin C was closely associated with MS and its related cardiovascular risk factors and might be useful as a tool of cardiovascular risk assessment.