Abstract: Objective · To explore the relationship of fibroblast growth factor-23 (FGF-23) and soluble klotho (sKL) with cardiac valve calcification in patients with continuous ambulatory peritoneal dialysis (CAPD). Methods · 147 CAPD patients the dialysis center of the First Affiliated Hospital of Soochow University were enrolled. The concentrations of FGF-23 and sKL were measuredenzyme-linked immunosorbent assays (ELISA). Echocardiography was applied to evaluate cardiac valve calcification. The patients were divided into normal cardiac valve group (group A) and cardiac valve calcification group (group B). SPSS 23.0 software was used for data analysis. Results · The incidence of cardiac valve calcification in CAPD patients was 54.42%. The risk of cardiac valve calcification showed positive correlation with age, dialysis age, serum creatinine, corrected calcium, serum phosphorus, serum alkaline phosphatase, parathyroid hormone, and the level of FGF-23 (P0.045, P0.022, P0.006, P0.024, P0.000, P0.017, P0.022, P0.000), and negative correlation with urea clearance index, the level of sKL and residual renal function (P0.045, P0.000, P0.011). Multivariate Logistic regression analysis showed that the increase of FGF-23 (OR5.007, 95% CI 1.446-17.339, P0.011) and serum phosphorus (OR7.433, 95% CI 1.558-35.470, P0.012) were two independent risk factors for cardiac valve calcification in CAPD patients, and the decrease of sKL (OR0.310, 95% CI 0.108-0.891, P0.030) was another independent risk factor as well. Receiver operator characteristic curves (ROC) indicated that to predict cardiac valve calcification in patients with CAPD, the optimal cut off points of FGF-23 and sKL were 2 172.64 pg/mL (sensitivity was 91.3%, specificity was 91%) and 231.88 pg/mL (sensitivity was 88.8%, specificity was 92.5%), respectively. Conclusion · The high level of FGF-23 and low level of sKL are two independent risk factors for cardiac valve calcification in CAPD patients. FGF-23 and sKL can be used to diagnose cardiac valve calcification in CAPD patients.

Key words: peritoneal dialysis, cardiac valve calcification, fibroblast growth factor-23 (FGF-23), soluble klotho (sKL)