Effects of conventional versus biocompatible peritoneal dialysis solutions on peritoneal and systemic inflammation, malnutrition and atherosclerosis in CAPD patients

Background: Chronic inflammation, malnutrition and atherosclerosis (MIA syndrome) are important predictors of high mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. We aimed to evaluate the effects of PD solutions (standard vs. biocompatible) on some parameters of MIA syndrome in patients undergoing CAPD. Methods: 42 stable patients who were on CAPD at least 2.5 years participated in this cross-sectional study. Patients who had severe anemia (Hb < 10 g/l), immunomodulatory therapy, peritonitis or any inflammatory conditions for at least 3 months before the analysis, malignant disease and acute exacerbation of heart failure, were excluded. 21 (50%) patients were treated with standard PD solutions (CAPDP-1), while the remaining 21(50% of patients) were treated with biocompatible PD solutions (neutral solutions with lower level of glucose degradation products and lower concentration of calcium, CAPDP-2). All patients underwent echocardiography and B-mode ultrasonography of common carotid arteries together with assessments of nutrition status and parameters of systemic and local inflammation. Results: There were no significant differences between the groups concerning age, gender, underlying disease, residual renal function, peritoneal transport characteristics, comorbidity or therapy applied. Patients from group CAPDP-2 had a significantly lower serum level of hs-CRP (3.7 +/- 2.6 mg/l vs. 6.3 +/- 4.5 mg/l; p = 0.023) and significantly better nutritional status confirmed by mid-arm circumference (p = 0.015), mid-arm muscle circumference (p = 0.002) and subjective global assessment (14.28% of patients in CAPDP-2 vs. 71% of patients in CAPDP-1 were malnourished; p = 0.000). Group CAPD-2 had less frequent left ventricular hypertrophy (p = 0.039), thinner intima-media thickness (p = 0.005), smaller carotid narrowing (p = 0.000) and fewer calcified plaques of common carotide arteries (p = 0.003). No significant difference between the CAPDP groups was observed in serum and effluent levels of inflammatory cytokines (IL-1, IL-6 and TNF-alpha) and CA-125 effluent level. Logistic regression analysis did not confirm that biocompatibility of PD solutions was an independent predictor of any parameter of MIA syndrome. Conclusions: According to the present study and logistic regression analysis, the effect of biocompatible CAPD solutions on parameters of malnutrition, inflammation and atherosclerosis have to be confirmed by well-designed and controlled studies in a higher number of patients.