The Association of Fibroblast Growth Factor-23 with Mineral Factors (Ca, P, and Mg), Parathyroid Hormone, and 25-Hydroxyvitamin D in Hemodialysis Patients: A Multicenter Study

Background: Fibroblast growth factor-23 (FGF23) is a phosphaturic factor that is released from bone. A variety of bone diseases can occur in renal diseases. Objectives: This study aimed to investigate the association of FGF23 with mineral factors, PTH, and 25-hydroxyvitamin D among hemodialysis patients. Methods: This cross-sectional multicenter study was performed on 135 patients aged 18 years or over with end-stage renal disease treated with hemodialysis maintenance. FGF-23, phosphorus, Ca, Mg, PTH, 25-hydroxyvitaminD, Uric Acid, Na, and K were measured in each patient’s fasting blood sample. We used univariate and multivariate linear regressions. Results: The mean age of patients was 56.45 13.64 years. The mean and median FGF23 concentration in patients were 855.07 43.33 and 762.6 (IQR = 456.6 - 1430.3) pg/mL, respectively. Different variables did not show any significant difference between the two sexes. After adjustment for age, sex, dialysis time, uric acid, Na, K, and kt/V, FGF23 had a linear association with 25-hydroxyvitamin D and every 10-unit (pg/mL) increase in FGF23 was significantly associated with a 0.03 mg/mL increase in 25-hydroxyvitamin D (P = 0.04). In addition, other variables showed no significant association with FGF23. Conclusions: According to the results, FGF23 had a linear association with vitamin D and an increase in FGF23 was significantly associated with an increase in vitamin D. In addition, there was no significant association between mineral factors and PTH, and FGF23.