KESESUAIAN KOLESTEROL LDL HASIL PERHITUNGAN SEJUMLAH FORMULA DENGAN KOLESTEROL LDL DIREK METODE ENZIMATIK

Increased cholesterol levels are the main cause of coronary heart disease. The results of examining LDL must be precise and accurate, but direct LDL examination (LDL-Direct) is quite expensive to do in a place with limited facilities so various experiments are carried out to get LDL formula (LDL-Cal) that is appropriate than formula commonly used, Friedewald formula. The aimed of this study was to determine the correlation between LDL cholesterol from calculation a number formulas with direct LDL cholesterol in order to obtain the best formula to be applied in laboratory of Lubuk Sikaping Hospital. This research was conducted on 75 patients who did lipid profile examination in laboratory of Lubuk Sikaping Hospital, who meet the inclusion criteria. Examination of total cholesterol, HDL, LDL and triglycerides were carried out by enzymatic methods on clinical chemistry analyzer. LDL cholesterol also calculated by several formulas namely Friedelwald formula (TC- (TG/5) -HDL), Chen formula (90% nonHDLC-10% TG), Anandaraja formula (0.9 TC- (0.9 TG/5) -28), Puavilai formula (TC-HDLC-TG/6), Vujovic formula (TC-HDLC-TG/3), and Cordova formula (3/4 (TC-HDLC.) Bland & Altman plot was used to compare the calculated LDL cholesterol level of each formula with the direct LDL. The mean LDL levels were 136.41 (35.92); 116.64 (32.72); 117.03 (30.83); 121.95 (32.79); 121.83 (33.23); 96.84 (32.47); 109.97 (28.24) for Direct, Friedelwald, Chen, Anandaraja, Puavilai, Vujovic, and Cordova respectively. Based on the Bland & Altman Plot, the calculation of LDL cholesterol from the Chen formula has the best compatibility with LDL-Direk with the mean difference of 19.3867 ± 19.0489 mg / dl at triglyceride levels <400 mg / dl, so it can be applied at RSUD Lubuk Sikaping with limited facilities. Keywords: LDL Cholesterol; LDL-Direct; LDL-CalAbstrakPeningkatan kadar kolesterol merupakan penyebab utama penyakit jantung koroner. Hasil pemeriksaan kadar LDL serum harus tepat dan akurat, namun pemeriksaan kadar LDL secara langsung (LDL-Direk) cukup mahal untuk dilakukan di tempat dengan fasilitas terbatas sehingga dilakukan berbagai percobaan untuk mendapatkan formula perhitungan LDL (LDL-Cal) yang lebih tepat dibandingkan formula yang telah umum digunakan yaitu formula Friedewald. Penelitian ini bertujuan untuk mengetahui kesesuaian antara kolesterol LDL hasil perhitungan sejumlah formula dengan kolesterol LDL direk sehingga diperoleh formula perhitungan terbaik untuk dapat diterapkan di laboratorium RSUD Lubuk Sikaping. Penelitian ini dilakukan terhadap 75 orang pasien yang melakukan pemeriksaan profil lipid lengkap ke Laboratorium RSUD Lubuk Sikaping. yang memenuhi kriteria inklusi. Pemeriksaan kolesterol total, HDL, LDL dan trigliserida dilakukan dengan metode enzimatik pada alat kimia klinik otomatis. Untuk kolesterol LDL juga dihitung dengan beberapa rumus yaitu formula Friedelwald (TC-(TG/5)-HDL). formula Chen (90%nonHDLC-10%TG), formula Anandaraja (0.9 TC- (0.9 TG/5)-28), formula Puavilai (TC-HDLC-TG/6), formula Vujovic (TC-HDLC-TG/3), dan formula Cordova (3/4 (TC-HDLC). Bland & Altman plot digunakan untuk membandingkan antara kadar kolesterol LDL hasil hitung masing-masing formula dengan LDL direk. Rerata kadar LDL (mg/dl) berturut-turut adalah 136,41 (35,92); 116,64 (32,72); 117,03 (30,83); 121,95 (32,79); 121,83 (33,23); 96,84 (32,47); 109,97 (28,24) untuk LDL-Direk, Friedelwald, Chen, Anandaraja, Puavilai, Vujovic, dan Cordova. Berdasarkan Bland & Altman Plot, perhitungan kolesterol LDL Formula Chen memiliki kesesuaian paling baik dengan LDL-Direk dengan selisih rerata 19,3867 ± 19,0489 mg/dl pada kadar trigliserida < 400 mg/dl, sehingga dapat diterapkan di RSUD Lubuk Sikaping dengan fasilitas yang terbatas.

Comparison of Formula-Based Methods with Diverse TGL: VLDL-C Ratio for Calculating LDL-C in a Tertiary Care Hospital

Background The most popular Friedewald formula (FF) was tailored with a fixed factor of 5 for triglyceride-very low-density lipoprotein cholesterol (TGL:VLDL-C) ratio. Some of the subsequent studies on diverse population demonstrated modified FF with only altered TGL:VLDL-C ratio, comprising either a fixed or an adjustable factor. Hata and Nakajima as well as Puavilai et al proposed fixed factors of 4 and 6, respectively. Recently, Martin et al recommended an adjustable factor derived as N-strata-specific median TGL:VLDL-C ratio based on TGL and non-high-density lipoprotein cholesterol (non-HDL-C). Aim This comparative retrospective study evaluates the efficacy of LDL-C formulae, varying only in TGL-VLDL-C ratio, using direct LDL-C assay as a reference method in a tertiary care hospital. Materials and Methods A total of 1,747 patient records with lipid profile data were procured. Concordance analysis, absolute difference, and post hoc test were employed as analytical tools. The impact of total cholesterol (TChol), TGL, and HDL-C on formulae was also evaluated. Results Overall, Martin equation had relatively the highest concordance, narrowest absolute difference, and minimal influence of TChol, TGL, and HDL-C. On the contrary, the Hata method revealed comparatively the lowest concordance, widest absolute difference, and high influence of TChol, TGL, and HDL-C. The remaining formula-based approaches, that is, FF and Puavilai calculation, executed mostly inconsistent intermittent features between Martin equation and Hata method. Conclusions Relatively dominant and competitive analytical attributes of the Martin equation with an adjustable TGL:VLDL-C factor outweigh the remaining three formulae-based methods with fixed TGL:VLDL-C factor in Indian adults.

Correlation of Direct LDL Versus Friedewald’s, Modified Friedewald’s and Anandraja’s Formula for Estimating LDL Cholesterol Levels along with LDH and Troponin I in Coronary Artery Disease Patients

The objective of the study is to compare the Friedewald formula, Modified Friedewald formula, and Anandaraja formula with direct homogeneous assay for low- density lipoprotein cholesterol (LDL-C) levels in CAD patients. Study Design is Cross-sectional study. Healthy subjects of both the gender, aged 18 - 75 years were included in this study. Lipid profile, LDH and Troponin I of both the controls and patients sample were collected from OPD of Central Hospital laboratory of Gayatri Vidhya Parishad Institute of Health Care and Medical Technology, Visakhapatnam. LDL-C estimation was done by direct homogenous assay and also calculated by using the Friedewald’s Formula, Modified Friedewald’s Formula and Anandaraja’s Formula for assessing and validity of the LDL cholesterol. LDH were measured kinetically UV method by Chem Ultra reagent system Pack and Cardiac Troponin I by JusCheck Rapid card test. One hundred samples were analyzed in this study, Out of that 50 are Known CAD patient samples and 50 are controls. The comparison of Lipid profile of Variable versus group. The P value also > 0.05 statistically significant. The Mean value for LDH in Case (Patients) is 486.2, whereas for control, it was 328.3. It shows highly significant for this parameter. The association between Case (Patients) and Control for Troponin I was highly significant in this study. In our study, we conclude that, modified friedewald’s formula was closure to the direct method. The performance of calculated methods was not uniform at different TG levels. Even though, Modified Friedewald’s formula is closure to Direct LDL, For laboratory setup, Novel and Innovative direct homogeneous assays are most reliable and accurate for the analysis of LDL cholesterol.

Comparing Calculated LDL with Direct Method: A Retrospective, Real-World Evidence Study on Diagnostic Lab Reports from A Single Center in India

Objective: To compare and validate the calculated LDL values from Friedewald and Anandaraja formulas with directly measured values in the Indian population. Material and Methods: The study was conducted on randomly selected 102 individuals of 16 to 88 years of age during December 2019. The direct LDL values were measured using selective solubilization assay, and Friedewald and Anandaraja formulas were used to calculate LDL for comparison. The correlations between direct and calculated methods were assessed using the linear regression method. Receiver operating characteristic analysis with nonparametric distribution was used to compare the sensitivity and specificity of the three methods. Results: The average LDL of direct method, 107.3 mg/dL, Friedewald formula, 89.7 mg/dL, and Anandaraja was 99.0 mg/dL. The relation between direct and calculated values assessed by linear regression showed 97% and 87% of correlation with Friedewald and Anandaraja, respectively. The ROC analysis inferred that direct (AUC 0.74; 95% CI 0.64-0.83) and Friedewald (AUC 0.71; 95% CI 0.61-0.81) methods had shown about 70% efficiency in predicting true positive and true negative dyslipidemia cases. In our dataset, the Anandaraja formula could not well differentiate positives from negative cases of dyslipidemia with merely 60% AUC. Conclusion: The underpredicted values from the Friedewald formula were associated with deranged cholesterol and HDL values, not triglycerides. Anandaraja formula overpredicted by 10 to 30 mg/dL when triglycerides were <150 mg/dL and underpredicted by 10-43 mg/dL while non-HDL was >140 mg/dL.

Reliability of Friedewald formula in patients with type 2 diabetes mellitus and its relation to lipid profile in diabetes regulation

Introduction: Many laboratories utilize Friedewald formula (FF) to analyze LDL cholesterol levels of patients including diabetes mellitus (DM). Therefore, it is essential to consider the coherence of results acquired by FF and direct measurement. The number of studies that investigated the effect of lipid parameters, especially TG/HDL cholesterol ratio, on the difference between the two methods is limited. The study was designed to compare LDL cholesterol values obtained by using FF with direct measurement, and to evaluate the relationship between diabetes regulation and lipid profile. Material and Methods: In the cross-sectional study, 529 type 2 DM patients and 1703 non-DM subjects were divided into four groups regarding TG concentrations. Unlike other studies, the study focuses on direct LDL (DLDL) cholesterol levels obtained with the help of different DLDL cholesterol kits (n=20). The correlations were implemented between HbA1c and lipid profiles. Results: It was determined that the bias% was over 10% in 24% of patients with 100-199 mg/dL TG levels. The parameter revealed that the most significant difference and the strongest correlation with HbA1c was TG/HDL cholesterol ratio in patients with type 2 DM. Conclusions: In patients with type 2 DM, even if it was TG <200 mg/dL, LDL calculated with FF should be evaluated together with the TG/HDL cholesterol ratio. Otherwise, direct measurement can be recommended. This ratio is related to diabetes regulation and may be used to monitor patients..

Does LDL-C or its phenotype actually predict the risk of cardiovascular diseases in the immediate future? An observational study

Background: Cardiovascular diseases (CVDs) are the leading cause of death and disability across the world. Dyslipidemia, and more specifically, elevated LDL-C has been historically attributed to be one of the key modifiable risk factors associated with atherogenesis. The aim of this study was to determine LDL-C and sdLDL-C, for establishment of their predictive value in the development of CVDs, in order for them to be used as clinical tools to guide the management of CVDs. Material and Methods: One hundred sixty-two (162) serum samples sent for the analysis of lipid profile parameters were studied, which were classified into tests and controls based on the values of calculated LDL-C obtained by Friedewald formula. These samples were then anonymized, and direct LDL-C was estimated using assay kits automatically. Then, sdLDL-C was calculated for all the samples using the arithmetic formula. After a period of six months, the samples were then deanonymized, and the various laboratory lipid profile parameters were correlated with the clinical outcomes in the form of cardiovascular events in the patients, to find out which parameter showed the best correlation.Results: It was observed from the present study that, neither calculated LDL-C (p=0.468) nor direct LDL-C (p=0.615) could be used singly as potential marker for the occurrence of a cardiovascular event in the immediate future. The calculated sdLDL-C also failed to demonstrate any such significance (0.642). Instead, the % sdLDL-C, both with respect to calculated and direct LDL-C, proved to be of higher predictive value. Conclusions:It can be concluded that LDL-C levels alone or the levels of its individual phenotypes cannot be singly used as surrogate markers suggestive of occurrence of any CVDs in the immediate future.

Impact of Adoption of Directly Measured Low-Density Lipoprotein-Cholesterol (LDL-C) on Targets of Lipid Control and Its Comparison With Friedewald Formula-Calculated LDL Cholesterol in People With Type-2 Diabetes Mellitus

Objectives: The accurate and precise measurement of low-density lipoprotein-cholesterol (LDL-C) is important in the assessment of atherosclerotic cardiovascular disease risk (ASCVD) in people with diabetes mellitus. This study aimed at comparing directly measured LDL-C with Friedewald formula (FF)-calculated LDL-C (c-LDL-C) in people with type-2 diabetes. Methods: Fasting lipid profiles of 1905 people with type-2 diabetes, whose LDL-C was estimated by direct LDL assay, were chosen for the study. In the same group, LDL-C was calculated with FF. Correlation and agreement between these methods were analyzed at various strata of triglycerides (TGs). The possibility of misclassifying people at various levels of LDL-C targets proposed in literature was calculated. Results: The mean LDL-C levels were lower in the c-LDL-C group across various TG strata. A significant correlation was found between c-LDL-C and direct LDL-C for all the study samples ( r = 0.948, P < .001) and across all TG strata. Analysis of agreement showed a positive bias for direct LDL-C which increased at higher strata of TGs. c-LDL-C underestimated ASCVD by misclassifying people at various LDL-C target levels. Conclusion: There is a difference between direct LDL-C and c-LDL-C values in people with diabetes and this may result in misclassifying ASCVD especially at lower levels of LDL-C and higher levels of TGs.