Background: Chronic renal insufficiency is accompanied by specific alterations of the lipoprotein metabolism. It has been suggested that the renal dyslipoproteinaemia of renal insufficiency contributes to the progression of glomerular and tubular lesions, with subsequent deterioration of renal function. The objective of this prospective study was to investigate whether the specific lipoprotein abnormalities of renal insufficiency are associated with the rate of decline of renal function in patients with moderately advanced chronic renal failure.
Methods: A patient population of 73 adult non-diabetic patients with primary chronic renal disease were followed with repeated measurements of the glomerular filtration rate (GFR) for an average of 3.2 (SD 0.7) years. Forty-three of these patients had chronic glomerulonephritis as the underlying renal disease. Patient characteristics including plasma levels of lipids and apolipoproteins were determined at entry and were prospectively related, using linear regression, to the rate of progression.
Results: The mean GFR at entry was 41.3 (SD 15.3) ml/min x 1.73 m2 BSA. The average rate of progression was a decline in GFR of -2.8 (SD 3.7) ml/min x 1.73 m2 BSA per year. In the whole patient study group total cholesterol, low-density lipoprotein (LDL) cholesterol, and apolipoprotein B (apoB) were all significantly associated with a more rapid decline in renal function, whereas triglycerides, high-density lipoprotein (HDL) cholesterol, and apolipoprotein A (apoA) were not. In the more homogeneous subgroup of patients with chronic glomerulonephritis the association between dyslipidaemia and the rate of progression was even more pronounced. In this subgroup of patients also serum triglycerides and apoE were significantly associated with a higher rate of progression. Both the initial blood pressure and proteinuria were also significantly associated with a more rapid decline in renal function in the whole study group as well as in patients with chronic glomerulonephritis. The associations between these variables with the rate of progression were all independent of the entry GFR values.
Conclusions: These results indicate that the lipoprotein abnormalities of renal insufficiency contribute to the progression of renal failure in human chronic renal disease.