Lipoprotein abnormalities without hyperlipidaemia in moderate renal insufficiency

摘要

To characterize lipoprotein metabolism during early renal insufficiency, plasma lipid and apolipoprotein profiles were determined in normotriglycer-idaemic (NTG,n=31) and hypertriglyceridaemic (HTG,n=30) middle-aged patients with primary renal disease and with moderately impaired renal function (GFR 20–55 ml/min, mean: 37.2). Mean GFR was similar in the two patient groups. They were compared with 102 normolipidaemic control subjects. In comparison with controls the NTG patients (plasma triglycer-ides TG≤1.7 mmol/l, mean TG: 1.16 mmol/l) had significantly increased plasma concentrations of apo C-III and apoB. The apoA-I levels tended to be lower and as a consequence the apoA-I/apoC-III ratio, considered to represent the hallmark of the altered apoli-poprotein profile in renal dyslipoproteinaemia, was markedly lower in NTG patients (8.7 versus 16.8,P<0.001). There was also a reduction of the antiatherogenic ratio apoA-I/apoB and an increase of the apoC-III/apoE ratio. The HTG patients (mean TG: 3.22 mmol/1) showed the same, but even more accentuated, qualitative changes as the NTG patients. There was a fourfold increase of apoC-III in VLDL-LDL lipoprotein fractions with little change in HDL in the HTG patients. In NTG patients the increase of apoC-III was found in VLDL-LDL and in HDL. Plasma insulin and PTH levels both correlated with the apoA-I/apoC-III ratio independently of GFR and BMI. This suggests a pathogenetic relationship between PTH-mediated alterations of insulin metabolism and the lipoprotein abnormalities. The findings of this study indicate that dyslipoproteinaemia in early renal insufficiency shares the same qualitative characteristics of that in advanced renal failure with accumulation of apoB-containing lipoproteins at various stages of delipidizat