A comparison of direct measurement of low density lipoprotein cholesterol level in serum with standard Friedewald, De-Long and modified Friedewald equation

Authors

  • Ahmad Khosravi دانشگاه علوم پزشکي شاهرود- کارشناس ارشد اپيدميولوژي
  • Majid Noorian بيمارستان امام حسين(ع) شاهرود -متخصص پاتولوژي باليني
  • Hossein Khosravi-Broojeni دانشگاه علوم پزشکي زنجان- گروه بیوشیمی و تغذیه
  • Hamid Kalalian-Moghaddam دانشگاه علوم پزشکي شاهرود- گروه علوم پایه
  • Hossein Ebrahimi دانشگاه علوم پزشکی شاهرود- گروه پرستاری

DOI:

https://doi.org/10.22100/jkh.v2i3.248

Keywords:

Low density lipoprotein, Triglyceride, Friedewald, Modified Friedewa-ld, De-long and direct measurement.

Abstract

Introduction: Reduction of low density lipoprotein cholesterol (LDL-C) in persons with coronary heart disease (CHD) is targeted. First step in treatment of lowering the LDL-C level is lifestyle modification including diet, weight reduction and exercise. At second step, the lipid lowering drug should be added. Although direct measurement of LDL-C from serum is most accurate, but it is not cost-effective, so laboratories usually use the Friedewald equation that suffers from several limitations such as hypertriglyceridemia and variability of lipoprotein composition. The authors compared and determined the correlation of LDL-C from enzymatic measurement with LDL-C from calculating.

 

Methods and Materials: A total of 475 fasting serum samples (199 males and 276 females with mean age of 56.3 years) with TG less than 400 mg/ dl in Imam Hossein hospital (Shahroud) were analyzed. According to serum TG levels, samples divided in four groups (<100, 100-199, 200-299, 300-400). Authors calculated the LDL-C and then compared with direct measurement. Data analyzed with SPSS and table curve packages.

 

Results: The comparison between direct and calculated methods showed that: 1) Concordance with the difference of 0±20 mg/dl is low. 2) Friedewald showed more accuracy compared with other calculated methods (51.2% versus 38.7% and 42.7%). 3) with the raising of TG, the accuracy declines and the overestimation increases. Correlation coefficient was 0.66.

 

Conclusion: An overestimation of approximately 0±20 mg/dl was found in over 50% of samples comparison with direct LDL-C. Therefore; direct measurement of LDL-C in patients with CHD is recommented.

References

صفا بخش شیدا، محمدي تربتی پیمان. مقایسه نتایج سنجش سطح سرمیLDL کلسترول به روش آنزیماتیک با روش محاسباتی فرید والد و دلونگ در بیمارستان لبافی نژاد در سال 84- 83. پژوهنده 1384؛ شماره 43: صفحات 19 تا 24.

Sempos C, Fulwood R, Haines C. The prevalence of high blood cholesterol levels among adults in the US. JAMA 1989; 262: 45- 52.

US Departement of health and human services. Report of the expert panel on population strategies for blood cholesterol reduction Bethesda Md: National heart, lung and blood institute 1990; NIH publication 90- 3047.

American heart association. What are healthy levels of cholesterol? [Cited September 6, 2006] Available from:http/www.americanheart.org/presenter.jhtml?identifier=183.

Bernard Henry J. Clinical diagnosis and management by laboratory methods. 20th ed. WB. Saunders Company; 2001.

Okada M, Ishida R. Direct measurement of low densi-ty-lipoprotein cholesterol is more effective than total cholesterol for the purpose of lipoprotein screening. Preventive Medicine 2001; 32: 224- 29.

McNamara JR, Cohn JS, Schaefer EJ. Calculated valu-es for low-density lipoprotein cholesterol in the assessment of lipid abnormalities and disease risk. Clin Chem 1990; 36(1): 36- 42.

Executive summary of the third report of national chol-esterol education program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (adult treatment panel III. JAMA 2001; 285: 2486- 97.

Puaviliai W, laoragpongse D. IS calculated LDL-C by using the new modified Friedewald equation better than the standard Friedewald equation? J Med Assoc Thai 2004; 87(6): 589- 92.

Nauck M, Warnick GR, Raffia N. Methods for measurement of LDL-C: A critical assessment of direct measurement by homogeneous assays versus calculation. Clin Chim 2002; 48(2): 236- 254.

Rifai N, Bachorik PS, Albers JJ. Lipids, lipoproteins. In: Burtis CA, Ashwood ER, editors. Tietz texbook of clinical chemistry. 3rd ed. Philadelphia: WB Saunders Company; 1999.p. 809- 61.

Bachorik PS, Ross JW. National cholesterol education program recommendations for measurements of low-density lipoprotein cholesterol: Executive summary national cholesterol education program working group on lipoprotein measurement. Clin Chem 1995; 41: 1414- 20.

Friedewald WT, Levy RI, Friedewald DS. Estimation of the concentration of low density lipoprotein cholesterol in plasma without use of the preparative ultracentrifuge. Clin Chem 1972; 18: 499- 502.

De Long DM, De Long ER, Wood PD. A comparison of methods for the estimation of plasma low- and very low density lipoprotein cholesterol: The lipid research clinics prevalence study. JAMA, 1986; 256: 2372- 2377.

Trembly AJ, Morrissette H, Gagne JM, Bergeron J, Gogne G, Couture P. Validation of the Friedewald formula for the determination of low-density lipoprotein cholesterol compared with ß-quantification in a large population. Clin Biochem, 2004; 37: 785- 790.

The long-term intervention with pravastatin in ische-mic disease (LIPID) study group. Prevention of cardiovascular events and death with pravastatin in patients with coronary heart disease and a board range of initial cholesterol levels. N Eng J Med 1998; 339: 1349- 57.

De Cordova CM.M. Schneider CR, Juttel ID, De Cor-dova MM. Comparison of LDL- cholesterol direct measurement with the estimate using the Friedewald formula in a sample of 10664 patients. Arquivos Brasileiros de Cardiologia 2004; 83(6): 482- 487.

Rifai N, Iannoti E, De Angelis K. Analytical and clin-ical performance of the homogenous enzymatic LDL- cholesterol assay compared with ultracentrifugation-dextran sulfate- Mg2+ method. Clin Chem1998; 44: 1242- 1250.

Nauck M, Graziani MS, Bruton D. Analytical and clinical performance of a detergent-based homogenous LDL-cholesterol assay: A multi center evaluation. Clin Chem 2000; 46: 506- 514.

Hata Y, Nakajima K. Application of Friedewald LDL- cholesterol estimation formula to serum lipids in Japanese population. Jpn Circ J1986; 20(12): 1191- 200.

Lindsey CC, Graham MR, Johnston TP, Kiroff CG, Freshly A. A clinical comparison of calculated versus direct measurement of low-density lipoprotein cholest- erol level. Pharmacotherapy 2004; 24(2):167- 172.

Rubies-Prat J, Reverter JL, Senti M, Pedro-Boter j, Salinas I, Lucas A, et al. Calculated low-density lipoprotein cholesterol should not be used for management of lipoprotein abnormalities in patients with diabetes mellitus. Diabetes Care,1993; 16: 1081- 6.

Hirany S, Li D, Jialal I. A more valid measurement of Low-density lipoprotein cholesterol in diabetic patients. Am J Med.1997; 102: 48- 53.

Winocour PH, Ishola M, Durrington PN. Validation of the friedewald formula for the measurement of low density lipoprotein cholesterol in insulin-dependent diabetes mellitus. Clin Chem Acta 1989; 79: 79- 83.

Branchi A, Torri A, Rovellini A, Sommariva D. Accuracy of calculated serum low-density lipoprotein cholesterol for the assessment of coronary heart disease risk in NIDDM patients. Diabetes Care 1998; 21(9): 1397- 1402.

Anandaraja S, Narang R, Godeswar r, laksmy R, Talwar KK. Low-density lipoprotein cholesterol estimation by a new formula in Indian population. Int J Cardiol, 2005; 102: 117- 120.

Tighe DA, Okene IS, Reed G, Nicolosi R. Calculated low density lipoprotein cholesterol levels frequently underestimated directly measured low density lipoprotein cholesterol determinations in patients with serum triglyceride levels =< 4.52 mmol/ l: An analysis comparing the Lipid direct magnetic LDL assay with the Friedewald calculation. Clinica Chimica Acta, 2006; 365: 236- 242.

Turkalp I, Cil Z, Ozkazank D. Analytical performance of direct assay for LDL-cholestrol: A comparative assessment versus Friedewald’s formula. Anadolu Kardyol Derg 2005; 5(1): 13- 17.

Branchi A, Rovellini A, Fiorenza AM, Torri A, Prandi W, Tomella C, et al. Estimation of cardiovascular risk: Total cholesterol versus lipoprotein profile. Int J Clin Lab Res1994; 24: 106- 112.

Smets EM, Pequeriaux NC, Blaton V, Goldschmidt HM. Analytical performance of a direct assay for LDL-cholesterol. Clin chem Lab Med 2001; 39: 270- 280.

Scharnagl H, Nauck M, Weiland H, Marz W. The Friedewald,s formula underestimates LDL-cholestrol at low concentrations. Clin Chem Lab Med 2001; 39: 426- 31.

Esteban-Salan M, Guimon-Usandizage I, Amoroto-Del-Rio E. Analytical and clinical evaluation of two homogenous assays for LDL-C in hyperlipidemic patients. Clin Chim. 2000; 46(8): 1121- 31.

Published

2007-12-10

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Section

Original Article(s)

How to Cite

A comparison of direct measurement of low density lipoprotein cholesterol level in serum with standard Friedewald, De-Long and modified Friedewald equation. (2007). Knowledge and Health in Basic Medical Sciences, 2(3), 47-55. https://doi.org/10.22100/jkh.v2i3.248

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