Is direct method of low density lipoprotein cholesterol measurement appropriate for targeting lipid lowering therapy?

Abstract

Objectives The aim of this study was to compare the Friedewald Formula with direct homogeneous low density lipoprotein cholesterol (LDL-C) assay for the detection of LDL-C levels. Methods Fasting serum samples were obtained for lipid analysis from 1001 patients. Total cholesterol (TC) and triglyceride (TG) levels were measured with enzymatic methods and the measurements of high density lipoprotein cholesterol (HDL-C) and LDL-C levels were detected using direct methods. Results The mean levels of serum TC, TG, HDL-C and LDL-C were detected with in the reference range. The LDL-C estimated by the Friedewald formula was significantly correlated ( P < 0.01) with the direct method but there was a negative bias among them. Conclusion Laboratories cannot use direct method as a substitute for Friedewald formula because direct method has not been standardized in large populations and increase cholesterol assay costs.