1
|
Paydaş Hataysal E, Körez MK, Yeşildal F, İşman FK. A comparative evaluation of low-density lipoprotein cholesterol estimation: Machine learning algorithms versus various equations. Clin Chim Acta 2024; 557:117853. [PMID: 38461864 DOI: 10.1016/j.cca.2024.117853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/10/2024] [Accepted: 03/01/2024] [Indexed: 03/12/2024]
Abstract
BACKGROUND Given the critical importance of Low-density lipoprotein cholesterol (LDL-C) levels in determining cardiovascular risk, it is essential to measure LDL-C accurately. Since the Friedewald formula generates incorrect predictions in many circumstances, new equations have been developed to overcome the Friedewald equations' shortcomings. This study aimed to compare estimated LDL-C with directly measured LDL-C (dLDL-C), as well as their performance in predicting LDL-C, utilizing Friedewald, extended Martin-Hopkins, Sampson, de Cordova, and Vujovic formulas and five machine learning (ML) algorithms. METHODS A total of 29,504 samples from the ISLAB-2 Core Laboratory were included in the study. All statistical analysis was performed using R version 4.1.2. Statistical Language. RESULTS Bayesian-Regularized Neural Network (BRNN) (r = 0.957) and Random Forest (RF) (r = 0.957) algorithms showed a higher correlation with dLDL-C than the other equations in all-testing dataset. All ML algorithms demonstrated less bias than pre-existing LDL-C equations with dLDL-C and outperformed the LDL-C estimation equations in terms of concordance in all-testing dataset. CONCLUSIONS The results of our research indicate that when compared to conventional equations, ML algorithms are much more effective in predicting LDL-C. ML algorithms, aided by a vast dataset, could have the capability to predict LDL-C levels even in cases where triglyceride levels are high, unlike the limited usage of Friedewald formula.
Collapse
Affiliation(s)
- Esra Paydaş Hataysal
- Department of Biochemistry, Göztepe Prof. Dr. Süleyman Yalçın City Hospital, Istanbul, Turkey.
| | - Muslu Kazım Körez
- Department of Biostatistics, Selcuk University Faculty of Medicine, Konya, Turkey
| | - Fatih Yeşildal
- Department of Biochemistry, Haydarpaşa Numune Training and Research Hospital, Istanbul, Turkey
| | - Ferruh Kemal İşman
- Department of Biochemistry, Göztepe Prof. Dr. Süleyman Yalçın City Hospital, Istanbul, Turkey
| |
Collapse
|
2
|
Nuwaylati DA, Awan ZA. A novel equation for the estimation of low-density lipoprotein cholesterol in the Saudi Arabian population: a derivation and validation study. Sci Rep 2024; 14:5478. [PMID: 38443422 PMCID: PMC10914719 DOI: 10.1038/s41598-024-55921-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 02/28/2024] [Indexed: 03/07/2024] Open
Abstract
Low-density lipoprotein cholesterol (LDL-C) is typically estimated by the Friedewald equation to guide atherosclerotic cardiovascular disease (ASCVD) management despite its flaws. Martin-Hopkins and Sampson-NIH equations were shown to outperform Friedewald's in various populations. Our aim was to derive a novel equation for accurate LDL-C estimation in Saudi Arabians and to compare it to Friedewald, Martin-Hopkins and Sampson-NIH equations. This is a cross-sectional study on 2245 subjects who were allocated to 2 cohorts; a derivation (1) and a validation cohort (2). Cohort 1 was analyzed in a multiple regression model to derive an equation (equationD) for estimating LDL-C. The agreement between the measured (LDL-CDM) and calculated levels was tested by Bland-Altman analysis, and the biases by absolute error values. Validation of the derived equation was carried out across LDL-C and triglyceride (TG)-stratified groups. The mean LDL-CDM was 3.10 ± 1.07 and 3.09 ± 1.06 mmol/L in cohorts 1 and 2, respectively. The derived equation is: LDL-CD = 0.224 + (TC × 0.919) - (HDL-C × 0.904) - (TG × 0.236) - (age × 0.001) - 0.024. In cohort 2, the mean LDL-C (mmol/L) was estimated as 3.09 ± 1.06 by equationD, 2.85 ± 1.12 by Friedewald, 2.95 ± 1.09 by Martin-Hopkins, and 2.93 ± 1.11 by Sampson-NIH equations; statistically significant differences between direct and calculated LDL-C was observed with the later three equations (P < 0.001). Bland-Altman analysis showed the lowest bias (0.001 mmol/L) with equationD as compared to 0.24, 0.15, and 0.17 mmol/L with Friedewald, Martin-Hopkins, and Sampson-NIH equations, respectively. The absolute errors in all guideline-stratified LDL-C categories was the lowest with equationD, which also showed the best classifier of LDL-C according to guidelines. Moreover, equationD predicted LDL-C levels with the lowest error with TG levels up to 5.63 mmol/L. EquationD topped the other equations in estimating LDL-C in Saudi Arabians as it could permit better estimation when LDL-C is < 2.4 mmol/L, in familial hyperlipidemia, and in hypertriglyceridemia, which improves cardiovascular outcomes in high-risk patients. We recommend further research to validate equationD in a larger dataset and in other populations.
Collapse
Affiliation(s)
- Dena A Nuwaylati
- Department of Clinical Biochemistry, Faculty of Medicine, University of Jeddah, 21959, Jeddah, Saudi Arabia.
| | - Zuhier A Awan
- Department of Clinical Biochemistry, Faculty of Medicine, University of Jeddah, 21959, Jeddah, Saudi Arabia
- Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, 21465, Jeddah, Saudi Arabia
| |
Collapse
|
3
|
Teiti I, Aubry M, Fernandes-Pellerin S, Patin E, Madec Y, Boucheron P, Vanhomwegen J, Torterat J, Lastère S, Olivier S, Jaquaniello A, Roux M, Mendiboure V, Harmant C, Bisiaux A, Rijo de León G, Liu D, Bossin H, Mathieu-Daudé F, Gatti C, Suhas E, Chung K, Condat B, Ayotte P, Conte E, Jolly N, Manuguerra JC, Sakuntabhai A, Fontanet A, Quintana-Murci L, Cao-Lormeau VM. Unravelling the determinants of human health in French Polynesia: the MATAEA project. Front Epidemiol 2023; 3:1201038. [PMID: 38455935 PMCID: PMC10911015 DOI: 10.3389/fepid.2023.1201038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/15/2023] [Indexed: 03/09/2024]
Abstract
Background French Polynesia is a French overseas collectivity in the Southeast Pacific, comprising 75 inhabited islands across five archipelagoes. The human settlement of the region corresponds to the last massive migration of humans to empty territories, but its timeline is still debated. Despite their recent population history and geographical isolation, inhabitants of French Polynesia experience health issues similar to those of continental countries. Modern lifestyles and increased longevity have led to a rise in non-communicable diseases (NCDs) such as obesity, diabetes, hypertension, and cardiovascular diseases. Likewise, international trade and people mobility have caused the emergence of communicable diseases (CDs) including mosquito-borne and respiratory diseases. Additionally, chronic pathologies including acute rheumatic fever, liver diseases, and ciguatera, are highly prevalent in French Polynesia. However, data on such diseases are scarce and not representative of the geographic fragmentation of the population. Objectives The present project aims to estimate the prevalence of several NCDs and CDs in the population of the five archipelagoes, and identify associated risk factors. Moreover, genetic analyses will contribute to determine the sequence and timings of the peopling history of French Polynesia, and identify causal links between past genetic adaptation to island environments, and present-day susceptibility to certain diseases. Methods This cross-sectional survey is based on the random selection of 2,100 adults aged 18-69 years and residing on 18 islands from the five archipelagoes. Each participant answered a questionnaire on a wide range of topics (including demographic characteristics, lifestyle habits and medical history), underwent physical measurements (height, weight, waist circumference, arterial pressure, and skin pigmentation), and provided biological samples (blood, saliva, and stool) for biological, genetic and microbiological analyses. Conclusion For the first time in French Polynesia, the present project allows to collect a wide range of data to explore the existence of indicators and/or risk factors for multiple pathologies of public health concern. The results will help health authorities to adapt actions and preventive measures aimed at reducing the incidence of NCDs and CDs. Moreover, the new genomic data generated in this study, combined with anthropological data, will increase our understanding of the peopling history of French Polynesia. Clinical trial registration https://clinicaltrials.gov/, identifier: NCT06133400.
Collapse
Affiliation(s)
- Iotefa Teiti
- Laboratory of Research on Emerging Viral Diseases, Institut Louis Malardé, Papeete, French Polynesia
| | - Maite Aubry
- Laboratory of Research on Emerging Viral Diseases, Institut Louis Malardé, Papeete, French Polynesia
| | | | - Etienne Patin
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
| | - Yoann Madec
- Institut Pasteur, Université Paris Cité, Epidemiology of Emerging Diseases Unit, Paris, France
| | - Pauline Boucheron
- Institut Pasteur, Université Paris Cité, Epidemiology of Emerging Diseases Unit, Paris, France
| | - Jessica Vanhomwegen
- Environment and Infectious Risk Unit, Laboratory for Urgent Response to Biological Threats, Institut Pasteur, Paris, France
| | - Jérémie Torterat
- Institut de la Statistique de la Polynésie Française, Papeete, French Polynesia
| | - Stéphane Lastère
- Clinical Laboratory, Centre Hospitalier de la Polynésie Française, Pirae, French Polynesia
| | - Sophie Olivier
- Clinical Laboratory, Institut Louis Malardé, Papeete, French Polynesia
| | - Anthony Jaquaniello
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
- Institut Pasteur, Data Management Core Facility, Paris, France
| | - Maguelonne Roux
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
- Institut Pasteur, Université de Paris, Bioinformatics and Biostatistics Hub, Paris, France
| | - Vincent Mendiboure
- Institut Pasteur, Université Paris Cité, Epidemiology of Emerging Diseases Unit, Paris, France
| | - Christine Harmant
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
| | - Aurélie Bisiaux
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
| | - Gaston Rijo de León
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
| | - Dang Liu
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
| | - Hervé Bossin
- Laboratory of Research in Medical Entomology, Institut Louis Malardé, Paea, French Polynesia
| | - Françoise Mathieu-Daudé
- Laboratory of Research in Medical Entomology, Institut Louis Malardé, Paea, French Polynesia
- UMR MIVEGEC-Infectious Diseases and Vectors, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Clémence Gatti
- Laboratory of Marine Biotoxins, UMR241-Ecosystèmes Insulaires Océaniens (EIO) (IFREMER, ILM, IRD, UPF), Institut Louis Malardé, Papeete, French Polynesia
| | - Edouard Suhas
- Unit on non-Communicable Diseases, UMR241-Ecosystèmes Insulaires Océaniens (EIO) (IFREMER, ILM, IRD, UPF), Institut Louis Malardé, Papeete, French Polynesia
| | - Kiyojiken Chung
- Laboratory of Research on Emerging Viral Diseases, Institut Louis Malardé, Papeete, French Polynesia
| | - Bertrand Condat
- Department of Gastroenterology, Centre Hospitalier de la Polynésie Française, Pirae, French Polynesia
| | - Pierre Ayotte
- Centre de Toxicologie du Québec, Institut National de Santé Publique du Québec, QC, Canada
| | - Eric Conte
- Maison des Sciences de l’Homme du Pacifique, Université de la Polynésie Française, Punaauia, French Polynesia
| | - Nathalie Jolly
- Center for Translational Sciences, Institut Pasteur, Paris, France
| | - Jean-Claude Manuguerra
- Environment and Infectious Risk Unit, Laboratory for Urgent Response to Biological Threats, Institut Pasteur, Paris, France
| | - Anavaj Sakuntabhai
- Functional Genetics of Infectious Diseases Unit, Department of Global Health, Institut Pasteur, Paris, France
| | - Arnaud Fontanet
- Institut Pasteur, Université Paris Cité, Epidemiology of Emerging Diseases Unit, Paris, France
- PACRI Unit, Conservatoire National des Arts et Métiers, Paris, France
| | - Lluis Quintana-Murci
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Human Evolutionary Genetics Unit, Paris, France
- Chair Human Genomics and Evolution, Collège de France, Paris, France
| | - Van-Mai Cao-Lormeau
- Laboratory of Research on Emerging Viral Diseases, Institut Louis Malardé, Papeete, French Polynesia
| |
Collapse
|
4
|
Ghalichi F, Saghafi-Asl M, Kafil B, Faghfouri AH, Jourshari MR, Naserkiadeh AA, Ostadrahimi A. Insulin Receptor Substrates Regulation and Clinical Responses Following Vanadium-Enriched Yeast Supplementation in Obese Type 2 Diabetic Patients: a Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Biol Trace Elem Res 2023; 201:5169-5182. [PMID: 36826713 DOI: 10.1007/s12011-023-03604-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 02/15/2023] [Indexed: 02/25/2023]
Abstract
Increasing evidence suggests that organic vanadium compounds are bioavailable and safe therapeutic agents with insulin-mimetic and insulin-enhancing features. The objective of the current study was to examine the effect of vanadium-enriched yeast (VEY) supplementation on the gene expression level of insulin receptor substrates and clinical manifestations of obese type 2 diabetic mellitus (T2DM) patients. In this randomized, double-blind, placebo-controlled clinical trial, 44 obese T2DM patients were randomly allocated into either VEY (0.9 mg/day vanadium pentoxide) or placebo group for 12 weeks. The mRNA expression level of protein tyrosine phosphatase 1B (PTP1B), phosphatase and tensin homolog (PTEN), mitogen-activated protein kinase (MAPK), ribosomal protein S6 kinase (S6K), and nuclear factor kappa-light-chain-enhancer of activated B cells (NFƘB) genes in the peripheral blood mononuclear cells, serum levels of metabolic parameters, anthropometric indices, as well as the quality of life, and dietary intake were collected at pre- and post-intervention phases. Analysis of covariance was performed to obtain the corresponding effect size. Results showed that VEY administration significantly decreased anthropometric indices and glycemic parameters and increased insulin sensitivity after adjusting for potential covariates (p < 0.05), in comparison to the placebo group. Additionally, VEY supplementation was significantly effective on MAPK, PTP1B, and NFƘB gene expression level, compared to the placebo group. No significant changes were noticed for dietary intake, quality of life, and lipid profile in the VEY group, compared to the placebo group. Overall, VEY supplementation can be considered as a promising safe adjunct therapy for improving anthropometric indices and glycemic parameters in T2DM patients.
Collapse
Affiliation(s)
- Faezeh Ghalichi
- Faculty of Nutrition and Food Sciences, Department of Clinical Nutrition, Tabriz University of Medical Sciences, Tabriz, Iran
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Saghafi-Asl
- Nutrition Research Center, Drug Applied Research Center, Department of Clinical Nutrition, Faculty of Nutrition & Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behnam Kafil
- Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Hossein Faghfouri
- Maternal and Childhood Obesity Research Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Mahtab Rajabi Jourshari
- Faculty of Nutrition and Food Sciences, Department of Clinical Nutrition, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amin Akbari Naserkiadeh
- Faculty of Nutrition and Food Sciences, Department of Clinical Nutrition, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Ostadrahimi
- Faculty of Nutrition and Food Sciences, Department of Clinical Nutrition, Tabriz University of Medical Sciences, Tabriz, Iran.
| |
Collapse
|
5
|
Sobhani SA, Kheirandish M, Rafati S, Rafat M, Shahbazi R, Azarbad A, Mahmoodi M, Eftekhar E, Kheirandish S. Development of a Modified Friedewald's Formula to Calculate Low-Density Lipoprotein in an Iranian Population. Iran J Med Sci 2023; 48:484-492. [PMID: 37786463 PMCID: PMC10541546 DOI: 10.30476/ijms.2022.95469.2683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 10/02/2022] [Accepted: 11/01/2022] [Indexed: 10/04/2023]
Abstract
Background Elevated low-density lipoprotein cholesterol (LDL-C) is a significant risk factor for cardiovascular diseases. LDL-C can be directly measured using various methods, but this requires expensive equipment. Currently, clinical laboratories estimate LDL-C based on Friedewald's formula (FF). We aimed to develop a modified formula based on directly measured LDL-C (D-LDL-C) values in a large population in Southern Iran and compare the results with various other estimation formulas. Methods The participants of this cross-sectional study were adults aged >18 years living in Southern Iran. Blood samples from 15,200 individuals were collected, and the measured lipid parameters were randomly divided into training (n=10,184) and validation (n=5,016) datasets. A new formula was developed using a linear regression model, and its accuracy was validated. Pearson's correlation and Cohen's kappa were used to determin the relationship between D-LDL-C and calculated LDL-C (C-LDL-C). Results The developed formula for the estimation of LDL-C was 0.857 total cholesterol (TC)-0.915 high-density lipoprotein cholesterol (HDL-C)-0.115 triglycerides (TG). Based on our proposed formula, for TG<150 and TG≥150 mg/dL, there was a significant correlation between mean values of D-LDL-C and C-LDL-C (r=0.985 and r=0.974, respectively). Compared to other formulas, C-LDL-C obtained from the proposed formula had the highest correlation with D-LDL-C. The agreement between D-LDL-C and C-LDL-C for TC<200, 200-239, and ≥240 mg/dL was 80.8%, 63.2%, and 67.4%, respectively, indicating a higher level of agreement than other formulas. Conclusion The new formula appears to be more accurate than FF when applied to the population of Southern Iran.
Collapse
Affiliation(s)
- Seyed Alireza Sobhani
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
- Department of Pathology, School of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Masoumeh Kheirandish
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Shideh Rafati
- Social Determinants in Health Promotion Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Milad Rafat
- Department of Medical Genetics, School of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Roghayeh Shahbazi
- Department of Cellular and Molecular Medicine, School of Medicine, University of Ottawa, Ottawa, Canada
| | - Abnoos Azarbad
- Department of Pharmacology, School of Pharmacy, Eastern Mediterranean University, Famagusta, North Cyprus, via Mersin 10, Turkey
| | - Masoumeh Mahmoodi
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Ebrahim Eftekhar
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Somayeh Kheirandish
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| |
Collapse
|
6
|
Martins J, Steyn N, Rossouw HM, Pillay TS. Best practice for LDL-cholesterol: when and how to calculate. J Clin Pathol 2023; 76:145-152. [PMID: 36650044 DOI: 10.1136/jcp-2022-208480] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/23/2022] [Indexed: 01/19/2023]
Abstract
The lipid profile is important in the risk assessment for cardiovascular disease. The lipid profile includes total cholesterol, high-density lipoprotein (HDL)-cholesterol, triglycerides (TGs) and low-density lipoprotein (LDL)-cholesterol (LDL-C). LDL-C has traditionally been calculated using the Friedewald equation (invalid with TGs greater than 4.5 mmol/L and is based on the assumption that the ratio of TG to cholesterol in very- low-density lipoprotein (VLDL) is 5 when measured in mg /dL). LDL-C can be quantified with a reference method, beta-quantification involving ultracentrifugation and this is unsuitable for routine use. Direct measurement of LDL-C was expected to provide a solution with high TGs. However, this has some challenges because of a lack of standardisation between the reagents and assays from different manufacturers as well as the additional costs. Furthermore, mild hypertriglyceridaemia also distorts direct LDL-C measurements. With the limitations of the Friedewald equation, alternatives have been derived. Newer equations include the Sampson-National Institutes of Health (NIH) equation 2 and the Martin-Hopkins equation. The Sampson-NIH2 equation was derived using beta-quantification in a population with high TG and multiple least squares regression to calculate VLDL-C, using TGs and non-HDL-C as independent variables. These data were used in a second equation to calculate LDL-C. The Sampson-NIH2 equation can be used with TGs up to 9 mmol/L. The Martin-Hopkins equation uses a 180 cell stratification of TG/non-HDL-C to determine the TG:VLDL-C ratio and can be used with TGs up to 4.5 mmol/L. Recently, an extended Martin-Hopkins equation has become available for TGs up to 9.04 mmol/L.This article discusses the best practice approach to calculating LDL-C based on the available evidence.
Collapse
Affiliation(s)
- Janine Martins
- Chemical Pathology, University of Pretoria, Pretoria, South Africa
| | - Nicolene Steyn
- Chemical Pathology, University of Pretoria, Pretoria, South Africa
| | - H Muller Rossouw
- Chemical Pathology, University of Pretoria, Pretoria, South Africa
| | - Tahir S Pillay
- Chemical Pathology, University of Pretoria, Pretoria, South Africa .,Chemical Pathology, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
7
|
Dintshi M, Kone N, Khoza S. Comparison of measured LDL cholesterol with calculated LDL-cholesterol using the Friedewald and Martin-Hopkins formulae in diabetic adults at Charlotte Maxeke Johannesburg Academic Hospital/NHLS Laboratory. PLoS One 2022; 17:e0277981. [PMID: 36516155 PMCID: PMC9749991 DOI: 10.1371/journal.pone.0277981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 11/07/2022] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATP III) and the European Society of Cardiology recommend using low-density lipoprotein cholesterol (LDL-C) as a treatment target for cholesterol lowering therapy. The Friedewald formula underestimates LDL-C in non-fasted and hypertriglyceridemia patients. This study aimed to compare measured LDL-C to calculated LDL-C in diabetic patients using the Friedewald and Martin-Hopkins formulae. METHODS The data of 1 247 adult diabetes patients were retrospectively evaluated, and included triglycerides (TG), LDL-C, total cholesterol, and high-density lipoprotein cholesterol that were measured on the Roche Cobas® c702. Passing-Bablok regression analysis was used to determine the degree of agreement between measured LDL-C and calculated LDL-C using both formulae. The Bland-Altman plots were used to assess the bias at medical decision limits based on the 2021 European Society of Cardiology (ESC) guidelines on cardiovascular disease prevention in clinical practice. RESULTS Both formulae showed a good linear relationship against measured LDL-C. However, the Martin-Hopkins formula outperformed the Friedewald formula at LDL-C treatment target <1.4mmol/L. The Friedewald formula and the Martin-Hopkins formula had 14.9% and 10.9% mean positive bias, respectively. At TG-C ≥1.7 mmol/L, the Martin-Hopkins formula had a lower mean positive bias of 4.2% (95% CI 3.0-5.5) compared to the Friedewald formula, which had a mean positive bias of 21.8% (95% CI 19.9-23), which was higher than the NCEP ATP III recommended total allowable limit of 12%. CONCLUSION The Martin-Hopkins formula performed better than the Friedewald formula at LDL-C of 1.4 mmol/L and showed the least positive bias in patients with hypertriglyceridemia.
Collapse
Affiliation(s)
- Mogomotsi Dintshi
- Departement of Chemical Pathology, National Health Laboratory Services and University of Witwatersrand, Johannesburg, South Africa
- * E-mail:
| | - Ngalulawa Kone
- Departement of Chemical Pathology, National Health Laboratory Services and University of Witwatersrand, Johannesburg, South Africa
| | - Siyabonga Khoza
- Departement of Chemical Pathology, National Health Laboratory Services and University of Witwatersrand, Johannesburg, South Africa
| |
Collapse
|
8
|
Fan G, Zhang S, Wu Q, Song Y, Jia A, Li D, Yue Y, Wang Q. A machine learning-based approach for low-density lipoprotein cholesterol calculation using age, and lipid parameters. Clin Chim Acta 2022; 535:53-60. [PMID: 35970405 DOI: 10.1016/j.cca.2022.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/05/2022] [Accepted: 08/04/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND Low-density lipoprotein cholesterol (LDL-C) is a critical biomarker for cardiovascular disease. However, no consensus exists on the best method for estimating LDL-C in Chinese laboratories. This study aimed to develop a machine learning (ML) method for LDL-C estimation. METHODS An extensive data set of 111,448 samples were randomized into five equal subsets. ML-based equations were developed using age, sex, and lipid parameters based on five-fold cross-validation. The trained ML equations were externally validated in three different data sets. The performance of the ML equations was compared with the Friedewald, Martin/Hopkins, and Sampson equations. RESULTS The selected ML equations showed less bias with direct LDL-C than other LDL-C equations in the Chinese population, including those with triglycerides (TG) ≥ 400 mg / dL and LDL-C < 40 mg / dL. The performance of the ML equations was less susceptible to age. External validation showed the generalization of the ML equations. CONCLUSIONS This study highlights the potential of integrating sex, age, and lipid parameters into the ML equations to obtain a more robust and reliable LDL-C calculation.
Collapse
Affiliation(s)
- Gaowei Fan
- Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Shunli Zhang
- Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Qisheng Wu
- Division of Pathology & Laboratory Medicine, Lu Daopei Hospital, Beijing, China
| | - Yan Song
- Department of Clinical Laboratory, Beijing Shangdi Hospital, Beijing, China
| | - Anqi Jia
- Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Di Li
- Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, China-Japan Friendship Hospital, Beijing, China
| | - Yuhong Yue
- Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Qingtao Wang
- Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.
| |
Collapse
|
9
|
Khan M, Ain QT, Nawaz A, Iqbal Khan M, Sadiq F. Indirect calculation of LDL using thirteen equations in Pakistani population. Clin Chim Acta 2022; 536:77-85. [PMID: 36165861 DOI: 10.1016/j.cca.2022.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/07/2022] [Accepted: 09/06/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND Owing to the atherogenic properties, low density lipoprotein cholesterol (LDL-C) is the primary target for treatment and diagnosis of cardiovascular diseases (CVDs), hence accurate measurement of LDL-C is critical. Despite the availability of direct measurement assays for LDL-C, it is routinely calculated by Friedewald equation in clinical settings in Pakistan mostly due to financial constraints. However, the validity of this equation is impacted by several factors, therefore several other equations have been developed for the calculation of LDL-C. MATERIALS AND METHODS LDL-C of 39,385 individuals measured directly by homogenous assays (dLDL) was compared with LDL-C calculated by thirteen equations (cLDL-C). Stratifications based on different lipids i.e., triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL) were made to check the validity of these equations across all ranges of lipid profile. The correlation and median difference between dLDL and cLDL-C was statistically analyzed. RESULTS Overall Teerakanchana equation displayed a strong positive correlation (ρ = 0.967) and least median difference (-8.81) with dLDL, followed by Martin equation (ρ = 0.967). For higher TG ranges (>500 mg/dL), Teerakanchana equation had the least median difference (1.31) and a strong correlation (ρ = 0.800). CONCLUSION Our data suggest that Teerakanchana equation may be employed as an alternative to Friedewald equation for Pakistani population.
Collapse
Affiliation(s)
- Madeeha Khan
- Directorate of Research, Shifa Tameer-e-Millat University, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan
| | - Qura Tul Ain
- Directorate of Research, Shifa Tameer-e-Millat University, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan
| | - Amjad Nawaz
- Directorate of Research, Shifa Tameer-e-Millat University, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan
| | - Mohammad Iqbal Khan
- Shifa Tameer-e-Millat University, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan; Department of Vascular Surgery, Shifa International Hospital, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan
| | - Fouzia Sadiq
- Directorate of Research, Shifa Tameer-e-Millat University, Pitras Bukhari Road, H-8/4, Islamabad 44000, Pakistan.
| |
Collapse
|
10
|
Abstract
PURPOSE OF REVIEW The reference method for low-density lipoprotein-cholesterol (LDL-C) quantitation is β-quantification, a technically demanding method that is not convenient for routine use. Indirect calculation methods to estimate LDL-C, including the Friedewald equation, have been used since 1972. This calculation has several recognized limitations, especially inaccurate results for triglycerides (TG) >4.5 mmol/l (>400 mg/dl). In view of this, several other equations were developed across the world in different datasets.The purpose of this review was to analyze the best method to calculate LDL-C in clinical practice by reviewing studies that compared equations with measured LDL-C. RECENT FINDINGS We identified 45 studies that compared these formulae. The Martin/Hopkins equation uses an adjustable factor for TG:very low-density lipoprotein-cholesterol ratios, validated in a large dataset and demonstrated to provide more accurate LDL-C calculation, especially when LDL <1.81 mmol/l (<70 mg/dl) and with elevated TG. However, it is not in widespread international use because of the need for further validation and the use of the adjustable factor. The Sampson equation was developed for patients with TG up to 9 mmol/l (800 mg/dl) and was based on β-quantification and performs well on high TG, postprandial and low LDL-C samples similar to direct LDL-C. SUMMARY The choice of equation should take into the level of triglycerides. Further validation of different equations is required in different populations.
Collapse
Affiliation(s)
- Janine Martins
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division
- Department of Public Health Medicine, School of Health System & Public Health, University of Pretoria, Pretoria, South Africa
| | - H Muller Rossouw
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division
| | - Tahir S Pillay
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division
| |
Collapse
|
11
|
Sankanagoudar S, Tomo S, Shukla RKG, Sharma P. Comparative Study of Calculated LDL-Cholesterol Levels with the Direct Assay in Patients with Hypothyroidism. J Lab Physicians 2022; 14:456-464. [DOI: 10.1055/s-0042-1748628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Abstract
Background Hypothyroidism is one among the many factors that predisposes one to coronary artery disease. As low-density lipoprotein-cholesterol (LDL-C) is associated with cardiovascular risk, calculated LDL-C should have good accuracy with minimal bias. Hypothyroidism alters the lipid composition of lipoproteins by the secretion of triglyceride-rich lipoproteins, which affects the calculation of LDL-C. The present study aimed to compare 13 different formulae for the calculation of LDL-C including the newly derived Martin's formula by direct assay in patients of hypothyroidism.
Method In this analytical cross-sectional study, a total of 105 patients with laboratory evidence of hypothyroidism, from January to June 2019, were studied, and blood samples were subjected for lipid profile analysis at central biochemistry laboratory. Calculated LDL-C was assessed by different formulae.
Result We observed that calculated LDL-C by Friedewald's, Cordova's, Anandaraja's, Hattori's, and Chen's formulae has bias less than ± 5 compared with direct LDL-C, with Anandaraja's formula having the lowest bias (2.744) and Cordova's formula having lowest bias percentage (−1.077) among them. According to the Bland–Altman plots, the bias in Friedewald's and Anandraja's were equally distributed below and above the reference line of direct LDL-C.
Conclusion This is the first study comparing different formulae for LDL-C calculation in patients with hypothyroidism. Anandaraja's formula was as equally effective as Friedewald's formula when used as an alternative cost-effective tool to evaluate LDL-C in hypothyroid patients. The recently proposed Martin's formula for calculated LDL-C had a higher bias when compared with Friedewald's and Anandaraja's formulae in patients with hypothyroidism.
Collapse
Affiliation(s)
| | - Sojit Tomo
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Ravindra Kumar G. Shukla
- Department of Endocrinology and Metabolism, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Praveen Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| |
Collapse
|
12
|
Waśkiel-burnat A, Niemczyk A, Chmielińska P, Muszel M, Zaremba M, Rakowska A, Olszewska M, Rudnicka L. Lipocalin-2 and insulin as new biomarkers of alopecia areata. PLoS One 2022; 17:e0268086. [PMID: 35639706 PMCID: PMC9154110 DOI: 10.1371/journal.pone.0268086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 04/21/2022] [Indexed: 11/19/2022] Open
Abstract
Lipocalin-2 and visfatin are proinflammatory adipokines involved in the regulation of glucose homeostasis. Their role has been described in numerous inflammatory skin diseases such as atopic dermatitis and psoriasis. Recently, an increased prevalence of metabolic abnormalities has been reported in patients with alopecia areata. The aim of the study is to determine the serum levels of lipocalin-2 and visfatin in patients with alopecia areata in comparison with healthy controls. Moreover, the serum levels of total cholesterol, low-density lipoprotein cholesterol (LDL-cholesterol), high-density lipoprotein cholesterol (HDL-cholesterol), triglycerides, fasting glucose, insulin, c-peptide, and homeostasis model assessment for insulin resistance (HOMA-IR) were evaluated. Fifty-two patients with alopecia areata and 17 control subjects were enrolled in the study. The serum levels of lipocalin-2 [mean ± standard deviation, SD: 224.55 ± 53.58 ng/ml vs. 188.64 ± 44.75, p = 0.01], insulin [median (interquartile range, IQR): 6.85 (4.7–9.8) μIU/ml vs. 4.5 (3.5–6.6), p<0.05], c-peptide [median (IQR): 1.63 (1.23–2.36) ng/ml vs. 1.37 (1.1–1.58), p<0.05)], and HOMA-IR [median (IQR): 1.44 (0.98–2.15) vs. 0.92 (0.79–1.44), p<0.05) were significantly higher in patients with alopecia areata compared to the controls. The serum concentration of insulin and HOMA-IR correlated with the number of hair loss episodes (r = 0.300, p<0.05 and r = 0.322, p<0.05, respectively). Moreover, a positive correlation occurred between insulin, HOMA-IR, c-peptide and BMI (r = 0.436, p <0.05; r = 0.384, p<0.05 and r = 0.450, p<0.05, respectively). In conclusion, lipocalin-2 and insulin may serve as biomarkers for alopecia areata. Further studies are needed to evaluate the role of insulin as a prognostic factor in alopecia areata.
Collapse
|
13
|
Waśkiel-Burnat A, Kotowska M, Dorobek WM, Smyk J, Gąsecka A, Niemczyk A, Blicharz L, Filipiak KJ, Olszewska M, Rudnicka L. Patients with alopecia areata are at risk of endothelial dysfunction: results of a case-control study. Clin Exp Dermatol 2022; 47:1517-1522. [PMID: 35357040 DOI: 10.1111/ced.15206] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/28/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Alopecia areata is an autoimmune form of hair loss which may affect any hair-bearing area. It has been suggested that alopecia areata is associated with an increased risk of metabolic and cardiovascular comorbidities. OBJECTIVES The aim of the study was to evaluate the early predictors of cardiovascular diseases (endothelial function and arterial stiffness) in patients with alopecia areata without prior cardiovascular disease in comparison with healthy controls. METHODS Fifty-two patients with alopecia areata (38 women and 14 men, mean age: 41 [30 - 52]) and 34 healthy controls matched for age, gender and body mass index were enrolled in the study. Endothelial dysfunction expressed as reactive hyperemia index (RHI) and arterial stiffness identified by augmentation index (AI@75) were assessed with the use of the Endo-PAT 2000 device. RESULTS Endothelial dysfunction was observed in 22/52 (42%) patients with alopecia areata and in 4/34 (12%) healthy controls (p=0.002). Moreover, mean RHI was lower in patients with alopecia areata in comparison with control subjects (1.90 ± 0.31 vs 2.11 ± 0.45; p=0.03). No significant difference was present in AI@75 between patients with alopecia areata and the controls. CONCLUSIONS Patients with alopecia areata show abnormalities in the early predictors of cardiovascular diseases. Regular cardiovascular screening might be appropriate in every patient with alopecia areata.
Collapse
Affiliation(s)
- Anna Waśkiel-Burnat
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Maja Kotowska
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Wioleta M Dorobek
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Julia Smyk
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Aleksandra Gąsecka
- 1st Chair and Department of Cardiology, Medical University of Warsaw, Banacha 1a, 02-097, Warsaw, Poland
| | - Anna Niemczyk
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Leszek Blicharz
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Krzysztof J Filipiak
- Institute of Clinical Sciences, Maria Sklodowska-Curie Medical Academy, Pałac Lubomirskich, Plac Żelaznej Bramy 10, 00-136, Warsaw, Poland
| | - Małgorzata Olszewska
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| | - Lidia Rudnicka
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warsaw, Poland
| |
Collapse
|
14
|
Abstract
OBJECTIVES To summarize and assess the literature on the performances of methods beyond the Friedewald formula (FF) used in routine practice to determine low-density lipoprotein cholesterol (LDL-C). METHODS A literature review was performed by searching the PubMed database. Many peer-reviewed articles were assessed. RESULTS The examined methods included direct homogeneous LDL-C assays, the FF, mathematical equations derived from the FF, the Martin-Hopkins equation (MHE), and the Sampson equation. Direct homogeneous assays perform inconsistently across manufacturers and disease status, whereas most FF-derived methods exhibit variable levels of performance across populations. The MHE consistently outperforms the FF but cannot be applied in the setting of severe hypertriglyceridemia. The Sampson equation shows promise against both the FF and MHE, especially in severe hypertriglyceridemia, but data are still limited on its validation in various settings, including disease and therapeutic states. CONCLUSIONS There is still no consensus on a universal best method to estimate LDL-C in routine practice. Further studies are needed to assess the performance of the Sampson equation.
Collapse
Affiliation(s)
- Jean Pierre E Ghayad
- Laboratory Medicine Department, Hôtel Dieu de France University Hospital, Beirut, Lebanon
| | - Vanda P Barakett-Hamadé
- Laboratory Medicine Department, Hôtel Dieu de France University Hospital, Beirut, Lebanon
- Faculty of Medicine, Université Saint Joseph, Beirut, Lebanon
| |
Collapse
|
15
|
P P A, Kumari S, Rajasimman AS, Nayak S, Priyadarsini P. Machine learning predictive models of LDL-C in the population of eastern India and its comparison with directly measured and calculated LDL-C. Ann Clin Biochem 2021; 59:76-86. [PMID: 34612076 DOI: 10.1177/00045632211046805] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND LDL-C is a strong risk factor for cardiovascular disorders. The formulas used to calculate LDL-C showed varying performance in different populations. Machine learning models can study complex interactions between the variables and can be used to predict outcomes more accurately. The current study evaluated the predictive performance of three machine learning models-random forests, XGBoost, and support vector Rregression (SVR) to predict LDL-C from total cholesterol, triglyceride, and HDL-C in comparison to linear regression model and some existing formulas for LDL-C calculation, in eastern Indian population. METHODS The lipid profiles performed in the clinical biochemistry laboratory of AIIMS Bhubaneswar during 2019-2021, a total of 13,391 samples were included in the study. Laboratory results were collected from the laboratory database. 70% of data were classified as train set and used to develop the three machine learning models and linear regression formula. These models were tested in the rest 30% of the data (test set) for validation. Performance of models was evaluated in comparison to best six existing LDL-C calculating formulas. RESULTS LDL-C predicted by XGBoost and random forests models showed a strong correlation with directly estimated LDL-C (r = 0.98). Two machine learning models performed superior to the six existing and commonly used LDL-C calculating formulas like Friedewald in the study population. When compared in different triglycerides strata also, these two models outperformed the other methods used. CONCLUSION Machine learning models like XGBoost and random forests can be used to predict LDL-C with more accuracy comparing to conventional linear regression LDL-C formulas.
Collapse
Affiliation(s)
- Anudeep P P
- Department of Biochemistry, 410775All India Institute of Medical Sciences Bhubaneswar, Bhubaneswar, India
| | - Suchitra Kumari
- Department of Biochemistry, 410775All India Institute of Medical Sciences Bhubaneswar, Bhubaneswar, India
| | - Aishvarya S Rajasimman
- Department of Radiodiagnosis, 410775All India Institute of Medical Sciences Bhubaneswar, Bhubaneswar, India
| | - Saurav Nayak
- Department of Biochemistry, 410775All India Institute of Medical Sciences Bhubaneswar, Bhubaneswar, India
| | - Pooja Priyadarsini
- Department of Biochemistry, 410775All India Institute of Medical Sciences Bhubaneswar, Bhubaneswar, India
| |
Collapse
|
16
|
Rossouw HM, Nagel SE, Pillay TS. Comparability of 11 different equations for estimating LDL cholesterol on different analysers. Clin Chem Lab Med 2021; 59:1930-1943. [PMID: 34384146 DOI: 10.1515/cclm-2021-0747] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/29/2021] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Low-density lipoprotein cholesterol (LDL-C) estimation is critical for risk classification, prevention and treatment of atherosclerotic cardiovascular disease (ASCVD). Predictive equations and direct LDL-C are used. We investigated the comparability between the Martin/Hopkins, Sampson, Friedewald and eight other predictive equations on two analysers, to determine whether the equation or analyser influences predicted LDL-C result. METHODS In two unpaired datasets, 9,995 lipid profiles were analysed by the Abbott Architect and 4,782 by the Roche Cobas analysers. Non-parametric statistics and Bland Altman plots were used to compare LDL-C. RESULTS On the Abbott analyser; the Martin/Hopkins, Sampson and Friedewald LDL-C were comparable (median bias ≤1.8%) over a range of 1-4.9 mmol/L. On the Roche platform, Martin/Hopkins LDL-C was comparable to Friedewald (median bias 0.3%) but not to Sampson LDL-C (median bias 25%). In patients with LDL-C <1.8 mmol/L and triglycerides (TG) ≤1.7 mmol/L, predicted LDL-C using Abbott reagents was similar between Martin/Hopkins, Sampson and Friedewald equations but not comparable using Roche reagents. Abbott reagents classified 10-20% of patients in the 1.0-1.8 mmol/L range (Martin/Hopkins 13.4%; Sampson 14.5%; Friedewald 16%; direct LDL-C 13.2%). Roche reagents classified 11-30% in the 1.0-1.8 mmol/L range (Martin/Hopkins 23%; Sampson 11%; Friedewald 25%; direct LDL-C 17%). CONCLUSIONS Performance of predictive equations is influenced by the choice of analyser for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and TG. Replacement of the Friedewald equation with Martin/Hopkins estimation to improve quality of LDL-C results can be safely implemented across analysers, whereas caution is advised regarding the Sampson equation.
Collapse
Affiliation(s)
- Helgard M Rossouw
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa
| | - Susanna E Nagel
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa
| | - Tahir S Pillay
- Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa.,Division of Chemical Pathology, University of Cape Town, Pretoria, South Africa
| |
Collapse
|
17
|
Martínez-Morillo E, García-García M, Concha MAL, Varas LR. Evaluation of a new equation for estimating low-density lipoprotein cholesterol through the comparison with various recommended methods. Biochem Med (Zagreb) 2020; 31:010701. [PMID: 33380888 PMCID: PMC7745159 DOI: 10.11613/bm.2021.010701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 09/09/2020] [Indexed: 11/12/2022] Open
Abstract
Introduction The accurate estimation of low-density lipoprotein cholesterol (LDL) is crucial for management of patients at risk of cardiovascular events due to dyslipidemia. The LDL is typically calculated using the Friedewald equation and/or direct homogeneous assays. However, both methods have their own limitations, so other equations have been proposed, including a new equation developed by Sampson. The aim of this study was to evaluate Sampson equation by comparing with the Friedewald and Martin-Hopkins equations, and with a direct LDL method. Materials and methods Results of standard lipid profile (total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL) and triglycerides (TG)) were obtained from two anonymized data sets collected at two laboratories, using assays from different manufacturers (Beckman Coulter and Roche Diagnostics). The second data set also included LDL results from a direct assay (Roche Diagnostics). Passing-Bablok and Bland-Altman analysis for method comparison was performed. Results A total of 64,345 and 37,783 results for CHOL, HDL and TG were used, including 3116 results from the direct LDL assay. The Sampson and Friedewald equations provided similar LDL results (difference ≤ 0.06 mmol/L, on average) at TG ≤ 2.0 mmol/L. At TG between 2.0 and 4.5 mmol/L, the Sampson-calculated LDL showed a constant bias (- 0.18 mmol/L) when compared with the Martin-Hopkins equation. Similarly, at TG between 4.5 and 9.0 mmol/L, the Sampson equation showed a negative bias when compared with the direct assay, which was proportional (- 16%) to the LDL concentration. Conclusions The Sampson equation may represent a cost-efficient alternative for calculating LDL in clinical laboratories.
Collapse
Affiliation(s)
| | - María García-García
- Department of Clinical Biochemistry, Hospital del Oriente de Asturias, Arriondas, Asturias, Spain
| | | | - Luis Rello Varas
- Department of Clinical Biochemistry, Hospital Universitario Miguel Servet, Zaragoza, Spain
| |
Collapse
|
18
|
Abstract
Background & Objective: Concentration of low-density lipoprotein (LDL) is a known risk factor for cardiovascular disease which is routinely measured or calculated as LDL-C in clinical laboratories. In order to decrease the cost, instead of its measuring, it is recommended to calculate it using multiple formulas that have been introduced up to now. The aim of this study was to assess the results of various formulas and comparison of these results with those of measuring method and to clarify the best formula for the Iranian population. Methods: Concentrations of total cholesterol (TC), triglyceride (TG), cholesterol of high-density lipoprotein (HDL-C) and LDL-C in serums of 471 overnight fasting individuals were measured and also LDL-Cs of these samples were calculated by eleven different formulas according to their TC, TG, and HDL-C concentrations. Subsequently, results of measured and calculated LDL-C were analyzed statistically by paired t-test, correlation coefficient, and Passing-Bablok regression. In addition, for clinical evaluation, the differences between calculated and measured mean results were calculated and compared with an allowable total error. Results: Paired t-test unraveled a significant difference between the results of measured and calculated LDL-C by various formulas. But for some formulas, these differences were not clinically significant. The best clinical and statistical agreement (correlation coefficient) was obtained by the Friedewald equation. Conclusion: By using validated methods which have correct calibration and control system for measuring TC, TG, and HDL-C, we can use the Friedewald formula for calculating LDL-C in serum samples with TG up to 400 mg/dL.
Collapse
Affiliation(s)
- Fereshteh Atabi
- Department of Biochemistry and Biophysics, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Reza Mohammadi
- Department of Biochemistry, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| |
Collapse
|