Newly-developed De Cordova’s Formula for Calculation of LDL Cholesterol in Bangladeshi Population

Abstract

Raised serum LDL cholesterol is an important modifiable risk factor for the development of atherosclerosis and cardiovascular disease. So the management of dyslipidaemia is mostly based on the concentration of LDL cholesterol. Friedewald’s formula is commonly used method to estimate LDL cholesterol in most clinical laboratories. However, this formula cannot reflect the actual figure of LDL cholesterol. In 2013, de Cordova developed a new simple formula to calculate LDL cholesterol without using serum TG which is said to be more accurate than Friedewald’s formula. The present study was designed to compare the formula-based calculated LDL cholesterol (Friedewald’s formula and de Cordova’s formula) with direct homogenous estimation. The objective of the present study was to evaluate of applicability of de Cordova’s formula for calculation of LDL cholesterol. By using non-probability sampling technique, 460 individuals were enrolled in the study who were attending in the one-point collection centre of BSMMU for lipid profile estimation. Subjects were categorized as normolipidaemic individuals and dyslipidaemic patients. Serum TC, TG, HDL cholesterol and LDL cholesterol were measured by direct automated method. LDL cholesterol was also calculated by Friedewald’s formula and de Cordova’s formula. Results were expressed as mean ± SD. Comparison was done by Pearson’s correlation test, agreement was done by BlandAltman agreement test between measured and calculated LDL cholesterol. The mean ± SD of measured LDL cholesterol was 132.99 ± 36.65 mg/ dL. LDL cholesterol calculated by Friedewald’s formula and de Cordova’s formula were 121.39 mg/dL and 116.81 mg/dL respectively. The limits of agreement between measured LDL cholesterol (direct method) and calculated LDL cholesterol by de Cordova’s formula were lowest and agreement was better for all dyslipidaemic subjects. de Cordova’s formula showed better agreement with measured LDL cholesterol (direct method) than Friedewald’s formula for approximate calculation of LDL cholesterol without using triglycerides.Keywords: LDL cholesterol, de Cordova’s formula, Friedewald’s formula