B-type Natriuretic Peptide And High Sensitivity C-reaction Protein In Relation To Left Ventricular Function In Patients With Chronic Kidney Disease

Objective:To observe B-type natriuretic peptide(BNP) and high sensitivity C-reaction protein(hs-CRP) in relation to left ventricular function and clinical parameters in patients with chronic kidney disease(CKD).Methods:Step 1: 72 chronic kidney disease(CKD) patients with 51 males and 21 females, aged 16-69 , average age 41.58±14.1 years were selected. Primary disease included chronic glomerulonephritis 58 cases, diabetic nephropathy 10 cases, hypertension kidney 3 cases, polycystic kidney 1 case. Glomerular filtration rate (GFR) was examined. The CKD patients were divided into three groups according to the GFR(units: ml/min/1.73m2): CKDⅢstage(30≤GFR<60)17 cases(14 males and 3 females) , CKDⅣstage(15≤GFR<30)20 cases(12 males and 8 females),and CKDⅤstage (GFR<15) 35 cases(25 males and 10 females). 15 cases were collected from healthy subjects with normal urine routine, normal liver function and renal function, without cerebrovascular disease, without cardiovascular disease, without high blood pressure history and without diabetes mellitus history. Step 2: Enzyme linked immunosorbent assay (ELISA)was applied to detect the plasma levels of BNP and hs-CRP of CKD patients and the control group. Each CKD patients underwent doppler echocardiography investigations. Doppler echocardiographic parameter included LVDd (left ventricular end diastolic dimension),LAD (left atrial dimension),LVPW (left ventricular posterior wall),IVS (interventricular septum) and EF (ejection fraction). left ventricular (LV) mass index(LVMI) were measured by Devereux formula {1.04×[(LVST+LVPWT+LVDd)~3-LVDd~3]-13.6}/BAS. According to the LVMI divide the subjects into groups with and without left ventricular hypertrophy. Step 3: Analyzed BNP and hs-CRP in relation to left ventricular function and clinical parameters in CKD patients. Clinical parameters included serum creatinine, uric acid, cholesterol, triglyceride, high density lipoprotein (HDL), low density lipoprotein(LDL), serum albumin, hemoglobin, immunoreactive parathyroid hormone(iPTH) and so on. Correlation analysis was processed between ELISA result and clinical parameters respectively. Step 4: To determine BNP and hs-CRP the significance between group means in the analysis of variance. Spearman correlation was used to determine the relationship between BNP and clinical, echocardiographic parameter. SPSS 13.0 statistical software was used to analyze the above-mentioned data, in which process the significance was set at p<0.05.Results1 The levels of BNP and hs-CRP in CKD patients :The levels of BNP in CKD patients were increased significantly compared to controls(1.59±0.59 vs 1.10±0.29) ng/ml (p<0.05). There was a trend of an increase in the levels of BNP with decreasing GFR. The levels of BNP in CKDⅢstage, CKDⅣstage and CKDⅤstage were as follows(1.10±0.33,1.49±0.58,1.82±0.59)ng/ml. CKDⅣstage and CKDⅤstage were significantly higher compared to controls (p<0.05). No significantly different was found between the patients of CKDⅢstage and the control groups (p>0.05).The levels of BNP in CKDⅤstage were increased significantly in patients compared to CKDⅢstage (p<0.05) and CKDⅣstage (p<0.05). BNP in CKDⅣstage were not significantly different from CKDⅢstage (p>0.05).The levels of hs-CRP were significantly higher in CKD patients in comparison with controls(12.23±10.49 vs 4.0±3.23) ug /ml (p<0.05). There was a trend of an increase in the levels of hs-CRP with decreasing GFR. The levels of hs-CRP in CKDⅢstage, CKDⅣstage and CKDⅤstage were as follows(7.83±5.63,12.47±10.97,14.23±11.57)ug /ml. Hs-CRP level of between groups were not significantly differents in CKD patients(p>0.05).2 Ventricular structure and function in CKD patients: There was a trend that echocardiographic parameter of LAD, LVDd, IVS and LVPW increased with the decrease of the level of eGFR, being contradictory to EF. Compared to CKDⅢstage, LVPW was significantly higher in CKDⅣstage(10±1.43vs 8.88±2.18) mm(p<0.05).The levels of LVMI progressive increased from CKDⅢpatients to CKDⅤpatients. The levels of LVMI in CKDⅤstage were increased significantly in patients compared to CKDⅢstage(163.50±49.65vs 133.64±46.73) g/m2 (p<0.05)and CKDⅣstage(163.50±49.65vs 130.04±39.17) g/m2 (p<0.05). LVMI in CKDⅣstage were not significantly different from CKDⅢstage.3 The relationship of BNP, hs-CRP and left ventricular hypertrophy(LVH) in CKD patients: The incidence of LVH progressive increased from CKDⅢpatients to CKDⅤpatients (29.41% vs55% vs71.43%), as well as the plasma levels of BNP in LVH patients. In CKD patients, BNP were significantly higher in patients with LVH in comparison to patients without LVH (1.75±0.64vs 1.29±0.43) ng/ml (p<0.05) and control groups (1.75±0.64vs 1.10±0.29) ng/ml (p<0.05). The levels of BNP in without LVH were increased significantly in patients compared to controls (p<0.05). In CKD patients, hs-CRP were significantly higher in patients with LVH in comparison to patients without LVH (15.24±11.61vs 8.02±6.89) ug /ml (p<0.05) and control groups (15.24±11.61vs 4.00±3.23) ug /ml (p<0.05). The levels of hs-CRP in without LVH were increased significantly in patients compared to controls (p<0.05).4 Spearman correlation with BNP and clinical, echocardiographic parameter in CKD patients: The BNP plasma levels in CKD patients were positively correlated with serum creatinine(r = 0.571,p<0.01),LAD(r=0.331, p<0.01),LVDd(r=0.351, p<0.01),IVS(r=0.351, p<0.01),LVPW(r=0.293, p<0.05),LVMI(r=0.406, p<0.01),serum creatinine(r = 0.571,p<0.01) and immunoreactive parathyroid hormone (r=0.481, p<0.01); as well as significant negative correlated of BNP plasma levels with hemoglobin(r=-0.327, p<0.01), EF(r=-0.243, p<0.01)and GFR(r=-0.564, p<0.01). No relationship was found between the levels of BNP and other clinical parameters (p>0.05).Conclusions 1 Plasma BNP and hs-CRP levels are elevated with the declining eGFR level.2 In CKD patients, plasma BNP and hs-CRP levels are significantly correlated with LVH. And they are significantly higher in patients with LVH.3 Plasma BNP levels provides strong predictive information about the future onset of CV events in CKD subjects.