Indian Journal of Medical Biochemistry

Register      Login

VOLUME 21 , ISSUE 2 ( July-December, 2017 ) > List of Articles

RESEARCH ARTICLE

Comparison of Different estimated Formulas with Direct Estimation of Low-density Lipoprotein Cholesterol

Dhara N Kanani, Avanish Mishra

Citation Information : Kanani DN, Mishra A. Comparison of Different estimated Formulas with Direct Estimation of Low-density Lipoprotein Cholesterol. Indian J Med Biochem 2017; 21 (2):151-156.

DOI: 10.5005/jp-journals-10054-0040

License: CC BY 3.0

Published Online: 01-12-2013

Copyright Statement:  Copyright © 2017; The Author(s).


Abstract

Introduction

Recent recommendations of the Adult Treatment Panel and the Adolescents Treatment Panel of the National Cholesterol Education Program make the low-density lipoprotein cholesterol (LDL-C) levels in serum the basis of classification and management of hypercholesterolemia. This makes accurate reporting of LDL-C decisive in the management of coronary heart disease (CHD). Direct measurement of LDL by homogeneous method is accurate but reagent is costly. Therefore, we have to compare different calculated LDL values with direct LDL (D-LDL) values.

Aim

The aim of this study was (1) to decide if LDL-C level was underestimated/overestimated after it was calculated using the formulae compared with direct measurement of LDL-C and (2) to choose the best calculated method that compares maximum with the direct method.

Materials and methods

We measured total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), D-LDL by direct homogeneous method in 500 fasting samples. Simultaneously, Friedewald's (F-LDL-C), modified Friedewald's (MF-LDL-C), and Anandaraja's (A-LDL-C) formulas were also used for calculation of LDL-C.

Results

A good correlation was found between D-LDL-C as compared with F-LDL-C, MF-LDL-C, and A-LDL-C. Pearson's coefficient of correlation between MF-LDL-C and D-LDL-C was 0.94, which was moderately higher than other calculated methods. Pearson's coefficient of correlation between A-LDL-C and D-LDL-C was 0.92 and F-LDL-C and D-LDL was 0.93.

Conclusion

In conclusion, among the three LDL-C formulas, the Friedewald formula and Anandaraja' s formulas give a higher percentage of error compared with the modified Friedewald formula Therefore, modified Friedewald's formula is better than the other two formulae for calculating LDL-C in a more cost-effective manner and can be used in large population studies.

How to cite this article

Kanani DN, Mishra A. Comparison of Different Estimated Formulas with Direct Estimation of Low-density Lipoprotein Cholesterol. Indian J Med Biochem 2017;21(2):151-156.


HTML PDF Share
  1. Serum cholesterol, lipoproteins, and the risk of coronary heart disease. The Framingham study. Ann Intern Med 1971 Jan;74(1):1-12.
  2. Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA 2001 May;285(19):2486-2497.
  3. Cholesterol reference method laboratory network (CRMLN). Atlanta (GA): Centers for Disease Control and Prevention; 2016. [cited 2016 Aug]. Available from: http://www.cdc.gov/labstandards/crmln_clinical.html.
  4. Analytical performance of a direct assay for LDL-cholesterol: a comparative assessment versus Friedewald's formula. Anadolu Kardiyol Derg 2005 Mar;5(1):13-17.
  5. Evaluation of methods for the measurement of low-density lipoprotein cholesterol. J Cardiovasc Pharmacol Ther 2005 Mar;10(1):45-54.
  6. Methods for measurement of LDL-cholesterol: a critical assessment of direct measurement by homogeneous assays versus calculation. Clin Chem 2002 Feb;48(2):236-254.
  7. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem 1972 Jun;18(6):499-502.
  8. Calculated values for low density lipoprotein cholesterol in the assessment of lipid abnormalities and coronary disease risk. Clin Chem 1990 Jan;36(1):36-42.
  9. A modified formula for calculating low-density lipoprotein cholesterol values. Lipids Health Dis 2010 May;9:52.
  10. Low-density lipoprotein cholesterol estimation by a new formula in Indian population. Int J Cardiol 2005 Jun;102(1):117-120.
  11. The accuracy in using modified Friedewald equation to calculate LDL from non-fast triglyceride: a pilot study. J Med Assoc Thai 2009 Feb;92(2):182-187.
  12. The 4-hydroxybenzoate/4-aminophenazone chromogenic system used in the enzymatic determination of serum cholesterol. Clin Chem 1978 Dec;24(12):2161-2165.
  13. Quantitative determination of serum triglycerides by use of enzymes. Clin Chem 1973 May;19(5):476-482.
  14. Serum triglycerides determined colorimetrically with an enzyme that produces hydrogen peroxide. Clin Chem 1982 Oct;28(10):2077-2080.
  15. Homogenous enzymatic direct assay for serum HDL cholesterol. J Clin Lab Inst Reag 1996;19:349-353.
  16. Homogenous assay of serum LDL Cholesterol on an auto analyzer. Clin Chem 1997 Jan;43(6):S260-S261.
  17. A leap above Friedewald formula for calculation of low-density lipoprotein-cholesterol. J Lab Physicians 2015 Jan-Jun;7(1):11-16.
  18. A comparison of calculated with direct measurement of low density lipoprotein cholesterol level. JCMCTA 2009;20(2):19-23.
  19. Does LDL-C estimation using Anandaraja's formula give a better agreement with direct LDL-C estimation than the Friedewald's formula? Indian J Clin Biochem 2012 Apr;27(2):127-133.
  20. Comparison of two methods of estimation of low density lipoprotein cholesterol, the direct versus Friedewald estimation. Indian J Clin Biochem 2005 Jul;20(2):54-61.
  21. Evaluation of different formulas for LDL-C calculation. Lipids Health Dis 2010 Mar;9:27.
  22. A direct measurement for LDL-cholesterol increases hypercholesterolemia prevalence: comparison with Friedewald calculation. J UOEH 2010 Sep;32(3):211-220.
  23. Abnormalities of lipoprotein metabolism in patients with the nephrotic syndrome. N Engl J Med 1990 Aug;323:579-584.
  24. Limitations of the Friedewald formula for estimating low-density lipoprotein cholesterol in alcoholics with liver disease. Clin Chem 1994 Mar;40(3):404-406.
  25. Calculated low-density lipoprotein cholesterol should not be used for management of lipoprotein abnormalities in patients with diabetes mellitus. Diabetes Care 1993 Aug;16(8):1081-1086.
  26. Effects of total cholesterol and triglyceride on the percentage difference between the low-density lipoprotein cholesterol concentrations measured directly and calculated using the Friedewald formula. Clin Chem Lab Med 2008 Feb;46(3):371-375.
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.