A new accurate, simple formula for LDL-cholesterol estimation based on directly measured blood lipids from a large cohort

Abstract

Background Low-density lipoprotein cholesterol (LDL-c) is the major measured parameter for cardiovascular risk assessment. The generally accepted formula (LDL-F) for estimating LDL-c developed by Friedewald and colleagues in 1972 using data from 448 individuals suffers from known inaccuracies at extremes of triglyceride (TG) and total cholesterol (TC) values. Methods We generated new formulas based on a large Brazilian database containing directly measured lipid values from 10,664 fasted individuals. This database LDL-c was measured by the LDL-C Select FS (DiaSys) system, a homogeneous method without centrifugation. The formulas were generated using linear and non-linear approaches, and the formula with the highest accuracy and simplicity for general clinical use was selected. Results The simple formula LDL-c = 3/4 (TC - HDL-c) provided an accurate estimate of LDL-c, a higher correlation with directly measured LDL (r = 0.93) compared with LDL-F (r = 0.87), and also a higher accuracy. Conclusions The new formula outperformed several other LDL-c formulas over a wide range of TC, HDL-c and TG values. The validation and application of this formula in other populations is warranted.