High density lipoprotein (HDL) particle composition in patients with end stage renal failure (ESRF) on chronic dialysis.

Abstract

Hypertriglyceridaemia, low high density lipoprotein (HDL) cholesterol level and reduced LDL particle size are the major features of uraemic dyslipidaemia. They are also found in the Insulin Resistance Syndrome. To examine alterations in HDL composition in patients on chronic dialysis and their relationship with insulin resistance. HDL particle size was determined in 33 patients on chronic haemodialysis (HD), 27 on chronic ambulatory peritoneal dialysis (CAPD) and 32 control non-diabetic subjects (C) without renal disease by non-denaturing 3-30% polyacrylamide gradient gel electrophoresis. A weighted HDL particle size score was calculated taking into account both HDL particle size and percentage total HDL protein concentration of each HDL band of the individual. Lipid and apolipoliprotein concentrations were determined in HDL2 and HDL3 particles obtained by sequential ultracentrifugation. In a subset of 24 control subjects and 22 subjects on HD, insulin sensitivity was also determined by an intravenous glucose tolerance test (IVGTT). HDL particles were found to be more triglyceride enriched and apoAI depleted in subjects on HD even though plasma triglyceride level was highest in patients on CAPD. Five subpopulations of HDL particles were identified by gradient gel electrophoresis in all subjects combined. In the subgroup of subjects who underwent IVGTT, the weighted HDL particle size score correlated positively with HDL cholesterol level (r = 0.6, p < 0.0005), LDL particle size (r = 0.47, p < 0.001), and insulin sensitivity (r = 0.48, p < 0.001), and negatively with plasma triglyceride level (r = 0.37, p < 0.01). We conclude that even though HDL cholesterol is reduced to a similar level in subjects on both forms of dialysis for end stage renal failure, abnormalities of HDL composition are more marked in subjects on HD. Reduction in HDL particle size is linked with insulin resistance and accompanies reduction in LDL particle size and hypertriglyceridaemia.