Application of cystatin C to diagnosis of early renal impairment in patients with hypertension

Objective To evaluate the applicability of serum cystatin C to diagnosis of early renal impairment in patients with hypertension.Methods Serum cystatin C and urine microprotein(UMP) were measured in 645 patients with normal serum Cr and BUN.The data and the blood pressure of the patients were analysed together.The patients were divided into normal renal function group(412 cases) and early renal impairment group(233 cases) according to their UMP results.Based on their blood pressure,the patients in the normal renal function group were further divided into normal blood pressure group(208 cases) and hypertension group(204 cases),and the patients in the early renal impairment group were further divided into normal blood pressure group(109 cases) and hypertension group(124 cases).Results When the renal function had no distinguishable impairment,cystatin C had no significant statistical difference between the hypertension group and normal blood pressure group(P0.05).When the renal function had early impairment,the mean of cystatin C in the group with hypertension [(1.06±0.23) mg/L)] was higher than that in the group with normal blood pressure[(1.02±0.22) mg/L,P0.05].Conclusion Analysis of serum cystatin C and UMP together would be helpful to estimating the early renal impairment of patients with hypertension effectively.