Association Of The Levels Of Serum High Sensitive C-reactive Protein And Interleukin-6 In CAPD Patients With Cardiac Structural And Function Changes

Objective: The aim of this study is to test the hypothesis that there is a relationship between serum interleukin-6(IL-6),high sensitive C-reactive protein(Hs-CRP)and cardiac structural and function changes in continuous ambulatory peritoneal dialysis ( CAPD ) patients, and that the high inflammatory factors levels may help to distinguish the crisis group with cardiac structural and function changes, so certain their value in the evaluation and prognosis of patients with CAPD.Methods: The subjects consisted of 30 patients with CAPD. Patients with previous myocardial infaction(MI), rheumatic heart disease, thyroid gland disease,tuberculosis, malignancy, acute infection were excluded. In all patients, blood samples were drawn to measure the levels of IL-6 and Hs-CRP. The data of disease history, complication,systolic pressure,diastolic pressure,serum creatinine(SCr),blood urea nitrogen(BUN),triglyceride(TG),total cholesterol(TCh),fasting blood-glucose, serum albumin ( Alb ) were noted in detail. Hospital echocardiogram was performed. The data of Left ventricular end-diastolic (LVEDV) , Left ventricular end-systolic volumes (LVESV) ,left ventricular ejection fraction (LVEF) , Left ventricular posterior wall thickness ( LVPWT ) and interventricular septum thickness( IVST) were obtained. The IL-6 and Hs-CRP levels of 20 healthy persons were measured to determine a threshold by which all the CAPD patients were divided into two groups: low IL-6 group and high IL-6 group. The data from the two CAPD groups were analyzed. A value P<0.05 was considered statistically significant.Results:1. The serum IL-6 level of the control group and the CAPD patients had significance (P<0.05).2. 10 pg/ml was chosen as a threshold to divide all the patients with CAPD into two groups:low IL-6 group(IL-6<10 pg/ml) and high IL-6 group (IL-6≥10pg/ml). The low IL-6 group was consisted of 9 patients and the high IL-6 group was consisted of 21 patients. The age,sex, fasting blood-glucose, diastolic pressure,BUN,SCr,TG between the two groups had no significance (P>0.05).Systolic pressure, TCh and serum Alb had significance (P<0.05).3. Hs-CRP levels in low IL-6 group and high IL-6 group differed significantly (P=0.000). It indicated Hs-CRP level rose with IL-6.4. The results of echocardiogram(LVEF, LVEDV, LVESV, LVESV, LVPWT) in low IL-6 group and the high IL-6 group were measured.All these parameters between two groups had significant difference (P<0.05).5. There were significantly positive correlations between IL-6 and Hs-CRP, LVEDV, LVESV, LVPWT, IVST. The correlation coefficients were respectively 0.534, 0.449,0.543,0.269,0.538 (P=0.000, 0.000, 0.000, 0.032, 0.000). IL-6 correlated negatively with LVEF (r=-0.350, P=0.005).6. Hs-CRP had positively correlation with LVESV, LVPWT and IVST (r=0.494, 0.422,0.489;P=0.000, 0.001,0.000), and had negative correlation with LVEF(r= -0.476, P=0.000),but had no significant correlation with LVEDV (r=0.152, P=0.228).7. Hs-CRP entered as independent variable in the logistic analysis with cardiac structural and function changes , while other parameters were deleted.Conclusion:1. Chronic microinflammatory exists in the CAPD patients, in which serum IL-6 and Hs-CRP rise markedly.2. There is a significantly negative relationship between elevated serum IL-6 and Hs-CRP and lower LVEF, and a significantly positive relationship between elevated serum IL-6 and Hs-CRP and cardiac structural and function changes. Hs-CRP level is an independent predictorof cardiac structural and function changes in CAPD patients. It may be an useful factor to evaluate the cardiac function and prognose the outcome.3. But in this study IL-6 didn't enter the regression equation, so it can't safely be concluded that IL-6 is the independent predictor of cardiac structural and function changes in CAPD patients. It needs further study in large sample.