Results: For conservative group, FGF-23 level correlated positively with level of urea, creatinine and inversely correlated with glomerular filtration rate (GFR); the level of urea, creatinine and GFR are the three most influential factors on FGF-23 level, the changes in level of urea, creatinine and GFR explain 30.6% and 29.5% and 11.2% respectively of change in FGF-23 level with p < 0.05.