Research On Serum Hepcidin Levels And Its Relationship With Bone Mineral Density In Patients With Chronic Kidney Disease Stage3-5 And Maintenance Hemodialysis

Objective To study the serum levels of hepcidin and its relationship with bone mineral density(BMD) in patients with chronic kidney disease stage3-5 and maintenance hemodialysis.Methods Thirty patients with initial diagnosis chronic kidney disease(CKD) and twenty patients with maintenance hemodialysis(MHD) were randomly selected from our hospital.Patients with initial diagnosis CKD were classified into group A(CKD stage3), group B(CKD stage4) and group C(CKD stage5) by estimation glomerular filtration rate(e GFR). Serum creatinine, calcium, phosphate and CRP were measured by Automatic biochemical analyzer in all patients. Intact parathyroid hormone(i PTH) was measured by Immune chemiluminescence. The levels of serum hepcidin in all patients were measured by ELISA. BMD and T-score for lumbar(L1-4) and femoral neck were measured by dual-energy X-ray absorptiometry in all patients. Differences of various factors in initial diagnosis CKD group(group A, B, C) were tested by One-way ANOVA.All factors in initial diagnosis CKD group and MHD group were compared by t-texts.Pearson correlation analysis and multiple stepwise linear regression analysis were used to examine correlations.Results1. Univariate analysis(1) The age and weight were not significantly different among patients with different groups.(2) The results that the levels of serum creatinine, calcium, phosphate, CRP, i PTH,hepcidin, femoral neck BMD, femoral neck T-score, lumbar BMD and lumbar T-score were not all equal showed by One-way ANOVA.(3) Compared group B with A, the levels of serum creatinine increased significantly(P<0.05), and e GFR, femoral neck BMD and lumbar T-score were lower(P<0.05).While serum calcium, phosphate, CRP, i PTH, hepcidin, femoral neck T-score and lumbar BMD were not significantly different among patients with group A and B.(4) Compared group C with A, the levels of serum creatinine, phosphate, CRP, i PTH and hepcidin increased significantly(P<0.05), while e GFR, serum calcium, femoral neck BMD, femoral neck T-score, lumbar BMD and lumbar T-score were lower(P<0.05).(5) Compared group C with B, the levels of serum creatinine, phosphate, i PTH and hepcidin increased significantly(P<0.05), and e GFR, femoral neck BMD, femoral neck T-score and lumbar T-score were lower(P<0.05).While serum calcium, CRP and lumbar BMD were not significantly different.(6) Compared MHD group with initial diagnosis CKD group, the levels of serum creatinine, phosphate, CRP, i PTH and hepcidin increased significantly(P<0.05),while serum calcium, femoral neck BMD, femoral neck T-score, lumbar BMD and lumbar T-score were lower(P<0.05).2. Pearson correlation analysis(1)In initial diagnosis CKD group, the levels of serum hepcidin was positively correlates with serum phosphate, i PTH and CRP( r=0.515, 0.489, 0.486, P<0.05),and it was negatively correlates with e GFR, serum calcium, femoral neck BMD, femoral neck T-score, lumbar BMD and lumbar T-score(r=-0.685,-0.371,-0.449,-0.478,-0.385,-0.643, P<0.05).(2)In MHD group, the levels of serum hepcidin was positively correlates with serum phosphate, CRP and i PTH(r= 0.460, 0.549, 0.450,P<0.05),and it was negatively correlates with femoral neck BMD, femoral neck T-score lumbar BMD and lumbar T-score(r=-0.554,-0.463,-0.571,-0.478, P<0.05).3. Multiple stepwise linear regression analysis(1) In initial diagnosis CKD group, eGFR and i PTH were independently associated with femoral neck T-score( β =0.352,-0.477; P=0.045, 0.008). Also, e GFR and i PTH were independently associated with lumbar T-score too( β =0.507,-0.366; P=0.026,0.003).(2)In MHD group, the levels of serum hepcidin was independently associated with femoral neck T-score and lumbar T-score(β=-0.463,-0.478,P=0.040, 0.033).Conclusions1. The levels of serum hepcidin will increase with eGFR decreased in patients with CKD, and its in MHD group higher than initial diagnosis CKD group.2. The levels of serum hepcidin was correlates with e GFR, serum calcium, phosphate,i PTH, CRP, femoral neck BMD, femoral neck T-score, lumbar BMD and lumbarT-score in patients with initial diagnosis CKD. e GFR and i PTH are independent factors for bone mass of femoral neck and lumbar in patients with initial diagnosis CKD.3. The levels of serum hepcidin was correlates with serum phosphate, i PTH, CRP,femoral neck BMD, femoral neck T-score, lumbar BMD and lumbar T-score in patients with MHD. Hepcidin may be independent factor for bone mass of femoral neck and lumbar in patients with MHD.