Effect of fluvastatin on intermediate density lipoprotein (remnants) and other lipoprotein levels in hypercholesterolemia

Abstract

The accelerated atherosclerosis in diseases associatedwith elevated remnant lipoprotein levels has directed interest toward the response of this lipoprotein species to lipid-lowering treatment. The effect of fluvastatin—a synthetic 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor—was compared with that of placebo on parameters of remnant metabolism in 57 patients with moderate hypercholesterolemia, but not heterozygous familial hypercholesterolemia, type III hyperlipidemia, or endogenous hypertriglyceridemia. Fluvastatin therapy resulted in decreases versus baseline in plasma total cholesterol, low density lipoprotein cholesterol (LDL-C) and LDL apolipoprotein (apo) B levels of 18%, 20%, and 18%, respectively (p < 0.01). Plasma parameters related to remnant metabolism were also significantly decreased: intermediate density lipoprotein by 43% and apo E by 22% (p < 0.01). The percent decrease in plasma intermediate density lipoprotein cholesterol level was twice that of LDL-C and 50% greater than the decrease seen in very low density lipoprotein cholesterol (VLDL-C), which was decreased by 28%. Total triglycerides were reduced by 11% and VLDL apo B by 24%, whereas high density lipoprotein cholesterol (HDL-C) rose significantly by 8%, HDL2-C by 24%, and HDL3-C by 3%. There were no increases in apo A-I levels compared with placebo nor any significant change in plasma lipoprotein(a) levels. The composition of LDL and VLDL particles did not appear to be altered by therapy, as assessed by the LDL-C:LDL-B, VLDL-C:VLDL-B, ortriglyceride:VLDL-B ratios. Further, there was no correlation between baseline triglycende levels and percent changes in remnant parameters. In conclusion, the HMG-CoA reductase inhibitor fluvastatin induced major reductions in indices of remnant lipoprotein concentrations, including intermediate density lipoprotein cholesterol and apo E. The total plasma apo E levels fell despite the increased HDL-C level, where more than half of the total apo E resides. The marked reduction in remnant lipoprotein, in addition to LDL-C with fluvastatin, may contribute to the antiatherosclerotic effect associated with this class of agents.