Cystatin C is Associated With Plaque Phenotype and Plaque Burden.

BACKGROUND/AIMS The relationship between carotid artery plaque burden, phenotype and serum cystatin C at normal and impaired renal function is still unclear. METHODS Demographic characteristics, carotid ultrasonography and other relevant information of 1,477 patients were collected. The association of carotid artery plaque burden, plaque phenotype with serum cystatin C was evaluated by strategy analysis based on renal function. RESULTS Serum cystatin C (OR=2.05, 95% CI: 1.83-2.29, P<.01) was a risk factor of stable plaque among patients with normal glomerular filtration rate. However, in the patients with mild impaired renal function, serum cystatin C was not only a risk factor for stable plaque (OR=1.60, 95% CI: 1.43-1.78, P<.001) but also was a risk factor for unstable plaque (OR=1.21, 95% CI: 1.10-1.32, P<.001). The smoothing function curve and a three-piecewise linear regression revealed that a nonlinear relationship was observed between serum cystatin C and plaque burden. When serum cystatin C was in the range of 0.75-1.30 (mg/L), the plaque burden tended to increase. CONCLUSION In normal renal function, serum cystatin C may confer stability of plaques. In mildly impaired renal function, serum cystatin C is a risk predictor of plaques. In normal renal function circumstances, serum cystatin C may benefit to the stability of plaques. In mild impaired renal function circumstances, serum cystatin C are a risk predictors of plaques.