Serum cystatin C levels correlate with vascular endothelial function in patients with essential hypertension

Objective: To investigate the association between serum cystatin C and vascular endothelial function in patients with essential hypertension. Methods: A total of 434 cases (male 228, female 206) with an average age of (56.5 +/- 12.0) years were enrolled in the first hospital of Shanxi Medical University, including 343 patients with essential hypertension and 100 patients without hypertension, ranging from May 2014 to October 2015. All patients were divided into the FMD >= 6.0% group (n=232) or FMD<6.0% group (n=202) according to flow mediated vasodilation (FMD) measured by ultrosound. The serum cystatin C, fasting blood glucose, serum lipid level, creatinine and urine micro albumin were measured in the morning after 12 hours fasting. The relationship between serum cystatin C and FMD was analyzed using the multiple linear regression analysis. Results: Serum cystatin C was significantly lower in the normal vascular endothelial function group than in the impaired vascular endothelial function group [(0.98 +/- 0.26) vs (1.05 +/- 0.23) mg/L, P<0.05]. Compared to the patients with grade 3 hypertension, FMD was significantly higher while serum cystatin C was significantly lower in the patients with grade 1 and 2 hypertension group (both P<0.05). FMD was negatively correlated with serum cystatin C, age and systolic blood pressure (r=-0.196, -0.347 and -0.205, all P<0.01). After adjusting for various confounders, muitiple linear regression analysis revealed that cystatin C was significantly associated with FMD (B=-2.310, P<0.01). Conclusion: Serum cystatin C was negatively correlated with vascular endothelial function in patients with essential hypertension.