Abstract:

Objective：To detect the serum level of FGF23 in CKD subjects with various degree of renal function and analyze the relationship between FGF23 and other biochemical parameters to explore the significance of serum FGF23 on mineral metabolism disorder in patients with CKD. Methodology: Intact serum FGF23 and other biochemical parameters were analyzed in seventy eight patients with various stages of CKD (eGFR ranged from 4～96 ml/min.), and 20 health volunteers were regarded as control. Results: (1) The level of serum FGF23 was elevated in all stages of CKD, LogFGF23 and inorganic phosphate (pi) showed significant higher in CKD 3, 4 and 5 comparing with that in CKD 1～2 but also happened in CKD 3, 4 and 5 themselves (P<0.01), which however did not occurred in CKD 3 with 1～2（P>0.05）; LogPTH showed significant differences in all stages while other biochemical parameters had none. (2)LogFGF23 was significantly and positively correlated with Pi（r=0.54, P<0.0001）, LogPTH（r=0.61, P<0.01） and 1,25(OH)2D3（r=0.32, P<0.01）, while negatively correlated with eGFR（r=-0.64, P< 0.0001）.(3)The difference of LogFGF23 between CKD with secondary hyperparathyroidism (SHPT) (4372± 1997pg/ml) and non- SHPT (2944± 19814 pg/ml) was also significant (P<0.01). The correlation between FGF23 and PTH was significant only in SHPT group（r=0.569, P <0.01）; while significant correlation between FGF23 and 1,25(OH)2D3 was only in non-SHPT group（r=0.437, P<0.05）. The negative correlations between FGF23 and eGFR in two sets were both significant and so were the positive correlations between FGF23 and Pi. (4) Multivariate linerar regression indicated that age, 1,25(OH)2D3, eGFR，serum albumin and “with SHPT”were significant impacting factor to FGF23 (P<0.05). Conclusions 1) The serum FGF23 was abnormal in early stage of CKD, and increased in parallel with the decline of renal function, which was significantly higher in end-stage renal disease. 2) Serum Pi was increased observably in end-stage of CKD, which stimulated FGF23 more significantly. The high level of serum FGF23 showed relationship to the happening of SHPT. 3) FGF23 can be affected by Age, 1,25(OH)2D3, renal function, nutritional quality and “with SHPT”.