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

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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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