The level of serum Klotho in patients with chronic kidney disease and its relationship with renal function

Objective To detect the level of serum Klotho in chronic kidney disease (CKD) 3-5 stage patients and explore its relationship with the progress of renal function.Methods Twenty-nine patients with CKD 3-5 stage (CKD group) and 10 cases of age-matched non-CKD patients (control group) were enrolled in the study.The level of serum Klotho and fibroblast growth factor 23 (FGF23) were measured by enzyme-linked immunosorbent assay.Results The level of serum Klotho in CKD group was significantly lower than that in control group [(670.07 ± 146.22) ng/L vs.(1 125.50 ± 126.96) ng/L] (P ＜ 0.01).The level of serum FGF23 in CKD group was significantly higher than that in control group[(48.89 ± 44.28) ng/L vs.(10.48 ± 8.93) ng/L] (P ＜ 0.01).Pearson correlation analysis showed that the level of Klotho in CKD patients was positively correlated with estimated glomerular filtration rate (eGFR) and hemoglobin,and Klotho was negatively correlated with log urea nitrogen,log serum creatinine,log FGF23 and phosphate.Multiple regression analysis showed that log FGF23 and serum phosphorus were independent factors for serum Klotho level in patients with CKD.CKD patients were divided into rapid progression of renal function group (10 cases) and renal stability group (19 cases) according to annual rate of eGFR dechne.The patients in rapid progression of renal function group with lower serum Klotho [(580.27 ± 162.15) ng/L vs.(717.33 ± 115.22) ng/L],higher uric acid and more severe proteinuria [(448.00 ±65.21) mmol/L vs.(368.32 ±78.80) mmol/L,(1.99 ± 1.57) g/d vs.(0.60 ± 1.00) g/d] (P ＜0.05).Conclusions Serum Klotho level of CKD 3-5 stage patients decreases with the decline in renal function.Serum phosphate and FGF23 are the independent factors for serum Klotho.Serum Klotho may become the prediction index of renal function progress for patients with CKD. Key words: Nephrosis;  Fibroblast growth factors;  Influencing factors