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A new formula for estimation of low-density lipoprotein cholesterol in an ethnic Chinese population

  • Ching-Yun Hu , Chia-Lin Lee , Wayne H.-H. Sheu , Jun-Sing Wang , I-Te Lee , Yuh-Min Song , Chia-Po Fu , Jiin-Tsae Ling , Yu-Fen Li and Shih-Yi Lin EMAIL logo
Published/Copyright: March 27, 2015
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Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 53 Issue 11

Abstract

Background: Low-density lipoprotein cholesterol (LDL-C) is an established risk factor for cardiovascular disease and is usually estimated by the Friedewald formula (FF) calculated from three parameters, namely, total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C). We aimed to develop a new and simple formula (NF) for LDL-C estimation.

Methods: This cross-sectional study enrolled two study populations (a testing group, n=16,749, and a validation group, n=4940). Linear regression analysis was used in the testing group to investigate the association between measured LDL-C (mLDL-C) and TC concentration, and was verified in the validation group.

Results: The NF yielded an estimated LDL-C (eLDL-C) equal to 0.75×total cholesterol–0.6465 (mmol/L). For the subjects with TC between 2.58 and 7.74 mmol/L, the difference between mLDL-C and eLDL-C using the NF was less than that from the FF (testing group: –0.04 to –0.20 vs. –0.28 to –0.38 mmol/L; validation group: 0.01 to –0.12 vs. –0.23 to –0.30 mmol/L; p<0.001, respectively). The predictability of the NF was not inferior to that of the FF in subjects with different triglyceride and HDL-C concentrations, and was not affected by diabetes diagnosis and statin use. However, the NF performed similar to or worse than the FF at TC concentrations <2.58 mmol/L and >7.74 mmol/L, respectively.

Conclusions: In the Chinese population, the accuracy of eLDL-C measurement with the NF was better than that with the FF, especially in subjects with TC levels between 2.58 and 7.74 mmol/L. The NF is simple and may be used for screening as well as for follow-up of patients on lipid lowering agents.

Keywords: Friedewald formula; low-density lipoprotein cholesterol; total cholesterol
Corresponding author: Shih-Yi Lin, MD, PhD, Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, No. 1650 Taiwan Boulevard Sect. 4, Taichung, Taiwan 40705, ROC, Phone: +886-4-23592525-3066, E-mail: ; and School of Medicine, National Yang Ming University, Taipei, Taiwan
aChing-Yun Hu and Chia-Lin Lee contributed equally to this work.

Acknowledgments

The authors would like to thank the Clinical Informatics Research & Development Center of Taichung Veterans General Hospital, Taichung, Taiwan, for data collection (F14043, F14051). Writing support was provided by Jim Ascencio, a native English speaker.

Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

Financial support: This study was funded by grants from the National Science Council (NSC 101-2314-B-075A-006-MY3) and Taichung Veterans General Hospital, Taichung, Taiwan, ROC (TCVGH-1030101C; TCVGH-1020101C; TCVGH-1013001C; TCVGH-1003001C).

Employment or leadership: None declared.

Honorarium: None declared.

Competing interests: The funding organisation(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

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Received: 2014-10-21
Accepted: 2015-3-1
Published Online: 2015-3-27
Published in Print: 2015-10-1

©2015 by De Gruyter

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https://doi.org/10.1515/cclm-2014-1029
Keywords for this article
Friedewald formula; low-density lipoprotein cholesterol; total cholesterol

Articles in the same Issue

  1. Frontmatter
  2. Editorials
  3. Laboratory medicine does matter in science (and medicine)… yet many seem to ignore it
  4. The standardization of the urine albumin assays: no longer deferrable
  5. Reviews
  6. The role of telomeres and vitamin D in cellular aging and age-related diseases
  7. Atypical hemolytic uremic syndrome: from diagnosis to treatment
  8. Clinical relevance and contemporary methods for counting blood cells in body fluids suspected of inflammatory disease
  9. EFLM Opinion Paper
  10. How to assess the quality of your analytical method?
  11. Genetics and Molecular Diagnostics
  12. Validation of CFTR intronic variants identified during cystic fibrosis population screening by a minigene splicing assay
  13. General Clinical Chemistry and Laboratory Medicine
  14. Uncertainty in measurement for 43 biochemistry, immunoassay, and hemostasis routine analytes evaluated by a method using only external quality assessment data
  15. A study examining the bias of albumin and albumin/creatinine ratio measurements in urine
  16. National survey on appropriateness of clinical biochemistry reporting in China
  17. Potentiometric measurement of urinary iodine concentration in patients with thyroid diseases with and without previous exposure to non-radioactive iodine
  18. Determination of 21-hydroxylase autoantibodies: inter-laboratory concordance in the Euradrenal International Serum Exchange Program
  19. Value of a commercial kit for detecting anti-C1q autoantibodies and correlation with immunological and clinical activity of lupus nephritis
  20. Comparison of the bead-based simultaneous analysis of specific platelet antibodies assay (SASPA) and Pak Lx Luminex technology with the monoclonal antibody immobilization of platelet antigens assay (MAIPA) to detect platelet alloantibodies
  21. Measurement of the inflammatory response in the early postoperative period after hip and knee arthroplasty
  22. Whole blood thromboelastometry profiles in women with preeclampsia
  23. Increased plasma soluble urokinase plasminogen activator receptor levels in systemic sclerosis: possible association with microvascular abnormalities and extent of fibrosis
  24. Reference Values and Biological Variations
  25. Reference ranges of serum bile acids in children and adolescents
  26. Infectious Diseases
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  29. Head-to-head comparison of 10 natriuretic peptide assays
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  34. Letter to the Editors
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  48. 47th National Congress of the Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC – Laboratory Medicine)
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