The Correlation Between Serum Uric Acid And Serum Calcium,Phosphorus,iPTH In Non Dialysis Patients With Chronic Kidney Disease Stage 4-5

Objectives:The prevalence rate of chronic kidney disease（CKD）increase with years in the world,which has developed into a major public health problem affecting human health.Chronic kidney disease-mineral and bone disorder（CKD-MBD）is one of the common complications of chronic kidney disease.To investigate the correlation between serum uric acid（SUA）and calcium,phosphorus,,iPTH in non dialysis patients with chronic kidney disease stage 4-5,we are conducting a retrospective study by collecting and analysing patients’data in Yiyang Central Hospital.Methods:Collecting the clinical data of 109 patients with chronic kidney disese stage 4-5 non dialysis（57males and 52females）who were treated in the Department of Nephrology of Yiyang Central Hospital of Hunan Province from July 2020 to July 2021,Including age,sex,weight,primary disease,and biochemical results such as Uric acid（UA）,creatinine（CR）,urea nitrogen（BUN）,hemoglobin（HB）,neutrophil,lymphocyte,platelet,albumin（ALB）,potassium（K⁺）,sodium（Na⁺）,chlorine（Cl^-）,magnesium(Mg²⁺),Serum iron,calcium,phosphorus,total cholesterol（TC）,triglyceride（TG）,high density lipoprotein（HDL）,low density lipoprotein（LDL）,parathyroid hormone（PTH）.Patients were divided into normal uric acid group（240 umol/L≤UA≤420 umol/L）and high uric acid group（UA>420 umol/L）,according to the SUA level.Comparing the differences of the general data and biochemical results between the two groups,and analysis the correlation between serum uric acid and serum calcium,phosphorus,iPTH.Results:1.This study has collected 109 patients totally,57 males and 52 females were included.And there were 50 patients in normal uric acid group,containing 18 cases of chronic nephritis,21 cases of diabetic nephropathy,5 cases of hypertensive nephropathy,2 cases of obstructive nephropathy,1 cases of congenital polycystic kidney,and 3 cases of other cases.The hyperuricemia group（HUA）has 59 patients,containing 21cases of chronic nephritis,20 cases of diabetic nephropathy,10 cases of hypertensive nephropathy,3 cases of obstructive nephropathy,2 cases of congenital polycystic kidney,1 cases of chronic interstitial nephritis,and 2cases of other cases.2.Cr,BUN,phosphorus,iPTH,neutrophil,platelet and neutrophil/lymphocyte ratio in HUA group were higher than the group with normal uric acid,while the calcium,e GFR and low density lipoprotein were lower than this（P<0.05）.No significant difference were found in primary disease,age,sex,weight,Hb,lymphocyte,platelet/lymphocyte ratio,ALB,K⁺,Na⁺,Cl^-,Mg²⁺,Serum iron,TG,TC,HDL,LDL between the two groups（P>0.05）.3.Uric acid was used as an independent variable,Pearson correlation analysis showed that UA was positively correlated with Cr,BUN,iPTH,phosphorus,neutrophil,neutrophil/lymphocyte ratio,and negatively correlated with e GFR,calcium（P<0.05）.There was no significant correlation between LDL and platelet,LDL（P>0.05）.4.Taking serum calcium,phosphorus and iPTH as dependent variables,multiple linear regression analysis was carried out by stepwise regression method.The results showed that e GFR（β=0.015,P=0.000）,UA（β=-0.000395,P=0.038）was an independent influencing factor of blood calcium.e GFR（β=-0.022,P=0.000）,BUN（β=0.018,P=0.001）was an independent influencing factor of blood phosphorus.e GFR（β=-10.294,P=0.000）,UA（β=0.296,P=0.009）is an independent influencing factor of iPTH.Conclusions:1.Serum uric acid in CKD4-5 patients was positively correlated with phosphorus and iPTH,and negatively correlated with calcium.2.Serum uric acid may have an effect on the occurrence and development of mineral metabolism disorder in CKD-MBD.3.In patients with CKD,serum uric acid may cause mineral metabolism disorder through inflammatory mechanism.