The commonest cause of death in patients with end-stage renal disease (ESRD) on maintenance haemodialysis (MHD) is coronary heart disease (CHD). It has been suggested that dyslipidaemia, an important CHD risk factor, may be worsened by dialysis. This study evaluated changes in blood lipoproteins and apolipoproteins after dialysis in ESRD patients on MHD.
The subjects were 57 (20 M, 37 F; 24 diabetic, 33 nondiabetic) patients with ESRD, aged 21-73 years, undergoing MHD at a major Dialysis Unit in Kuwait. Pre- and post-dialysis non-fasting blood samples were collected from each subject on the same day, and analyzed for plasma glucose, urate, triglycerides (TG), total cholesterol (TC), HDL, LDL and apolipoprotein (apo) A1 and B. Pre- and post-dialysis levels for each of the analytes were compared for the diabetic and non-diabetic subgroups of patients and linear correlations sought between Delta values (corresponding to differences between pre- and post-dialysis levels) of the lipoproteins and apolipoproteins.
There was a general trend towards significant increases in post-dialysis TC, HDL, LDL, and non-HDL levels in both sub-groups, and additionally for the non-diabetic, TG, apo A1 and apo B. The pre- to post-dialysis increases were essentially similar for the diabetic and non-diabetic groups-Diabetic: TC 14%, HDL 25%, LDL 19%, non-HDL 16%, apo A1 14%, apo B 10%; Non-diabetic: TC 20%, TG 29%, HDL 25%, LDL 26%, non-HDL 21%, apo A1 14%, apo B 14%. Generally, there were significant correlations between Delta values for the lipoproteins and apolipoproteins (r, 0.50-0.92) in both groups.
Levels of atherogenic lipoproteins increase post-dialysis in diabetic and non-diabetic patients with ESRD and the changing levels of these lipoproteins correlate significantly with corresponding changes in levels of apolipoproteins. The increase in lipid levels is therefore related to retention of apo A1 and B with each dialysis. We speculate that, with repeated dialysis, dyslipidaemia may get progressively worse and further accentuate CHD risk.