Comparison of Different estimated Formulas with Direct Estimation of Low-density Lipoprotein Cholesterol

ABSTRACT Introduction Recent recommendations of the Adult Treatment Panel and the Adolescents Treatment Panel of the National Cholesterol Education Program make the low-density lipoprotein cholesterol (LDL-C) levels in serum the basis of classification and management of hypercholesterolemia. This makes accurate reporting of LDL-C decisive in the management of coronary heart disease (CHD). Direct measurement of LDL by homogeneous method is accurate but reagent is costly. Therefore, we have to compare different calculated LDL values with direct LDL (D-LDL) values. Aim The aim of this study was (1) to decide if LDL-C level was underestimated/overestimated after it was calculated using the formulae compared with direct measurement of LDL-C and (2) to choose the best calculated method that compares maximum with the direct method. Materials and methods We measured total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), D-LDL by direct homogeneous method in 500 fasting samples. Simultaneously, Friedewald's (F-LDL-C), modified Friedewald's (MF-LDL-C), and Anandaraja's (A-LDL-C) formulas were also used for calculation of LDL-C. Results A good correlation was found between D-LDL-C as compared with F-LDL-C, MF-LDL-C, and A-LDL-C. Pearson's coefficient of correlation between MF-LDL-C and D-LDL-C was 0.94, which was moderately higher than other calculated methods. Pearson's coefficient of correlation between A-LDL-C and D-LDL-C was 0.92 and F-LDL-C and D-LDL was 0.93. Conclusion In conclusion, among the three LDL-C formulas, the Friedewald formula and Anandaraja' s formulas give a higher percentage of error compared with the modified Friedewald formula Therefore, modified Friedewald's formula is better than the other two formulae for calculating LDL-C in a more cost-effective manner and can be used in large population studies. How to cite this article Kanani DN, Mishra A. Comparison of Different Estimated Formulas with Direct Estimation of Low-density Lipoprotein Cholesterol. Indian J Med Biochem 2017;21(2):151-156.