BACKGROUND

Accumulating studies have shown that cystatin C may play important roles in the pathogenesis of arteriosclerosis. However, the association between serum cystatin C and the characteristics of carotid plaques has not been elucidated. Furthermore, the diagnostic value of serum cystatin C in carotid stenosis has not been studied.

METHODS

Serum cystatin C in 156 patients with acute ischemic stroke (AIS) in the carotid artery was measured by ELISA. Intima-media thickness (IMT), stenosis of the symptomatic common carotid artery (CCA), extra/intracranial internal carotid artery (ICA) stenosis, and plaque characteristics were measured and recorded. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value of serum cystatin C in carotid stenosis.

RESULTS

One hundred fifty-six patients were divided into two groups based on their cystatin C levels. The degree of arteriosclerosis, the severity of plaques, and stenosis of the symptomatic CCA were significantly higher in the patients with high cystatin C levels. In addition, the rate of unstable plaques was significantly higher in those with high cystatin C. Serum cystatin C levels of 1.075 and 1.125 mg/L had diagnostic value in distinguishing stenosis of CCA and extracranial ICA, respectively.

CONCLUSIONS

Higher cystatin C levels were strongly correlated with symptomatic CCA stenosis and the rate of unstable plaques. Analysis of cystatin C levels may be useful for the identification of CCA stenosis and extracranial ICA in patients with AIS.