RESUMO
Oxidative stress has been shown in (ESRD) patients specially those receiving regular haemodialysis (HD) in relation with an increased production of toxic free radicals due to membrane-induced complement leukocyte activation. An imbalance between oxidants and antioxidans has been suggested in uremic patients on HD. The respective influence of uremia and dialysis procedure has not been evaluated. Studies that have probed into the mechanism of oxygen radical production have implicated the bio-incompatibility of dialysis membranes. The effect of different dialysis membranes on lipid, lipoproteins, lipid peroxidation and total antioxidant capacity in ESRD patients on regular HD was studied. One hundred subjects were selected; 20 healthy controls, 20 chronic renal failure (CRF) patients on conservative drug management and 60 CRF patients on maintenance HD (20 dialyzed by polysulfone, 20 by hemophan and 20 by cuprophane membranes). All patients were matched for age, sex, gender and etiology of ESRD and HD patients for duration of dialysis. In addition to routine tests (Hb% and creatinine clearance in healthy control group and CRF patients on conservative management), total cholesterol, triglycerides, high density lipoprotein (HDL-C) and low density lipoprotein (LDL-C), apolipoprotein A (Apo A), apolipoprotein B (Apo B), serum malondialdehyde (MDA) and plasma total antioxidant status (TAS) were estimated. MDA was significantly higher and TAS was lower in uremic patients treated conservatively or by HD than in controls. MDA was significantly higher in HD than CRF patients on conservative management with least significant difference in HD patients treated by polysulfone followed by hemophan and then cuprophane membrane, while only cuprophane group showed lower levels of TAS compared to CRF patients on conservative management. HDL-C and Apo A was higher in polysulfone and hemophan than cuprophane group while triglyderide was lower. Polysulfone group showed lower levels of LDL-C than both cuprophane and hemophane groups thus providing less atherogenic lipid profile. There was a positive correlation between Hb% and TAS and a significant negative correlation between MDA and Hb%. There was a significant negative correlation between TAS and duration of dialysis in HD patients. In CRF patients on conservative management we obtained a significant positive correlation with TAS and a significant negative correlation with MDA.
