Comparison of ten formulae for calculating low-density lipoprotein cholesterol with direct low-density lipoprotein cholesterol measurement

Abstract

Background Accurate lipid profile assessment, mainly low-density lipoprotein cholesterol (LDL-C) measurement, is crucial for diagnosing and managing cardiovascular disease (CVD). The widely used Friedewald formula for LDL-C calculation has limitations, prompting the exploration of alternative equations. Aims This study aims to compare ten LDL-C calculation formulas with direct measurement among study participants attending a tertiary care centre. Materials and Methods Conducted from September 2021 to July 2022 at a tertiary healthcare centre in India, the study involved 114 participants aged 18 years or older. The exclusion criteria were high-serum triglyceride (TG) levels, renal failure, diabetes, liver diseases or unwillingness to participate. Blood samples were analysed for total cholesterol, TG, high-density lipoprotein cholesterol and LDL-C. The very-low-density lipoprotein cholesterol level was calculated. The LDL-C formulas evaluated were Friedewald, Anandaraja, De Cordova, Vujovic, Ahmadi, Puavillai, Chen, Hattori, Martin–Hopkin and Sampson. Results Vujovic’s formula showed a negligible mean difference and strong correlation (r = 0.916, P < 0.001) with direct LDL-C estimation across TG concentrations. Sampson’s formula performed best for TG <150 mg/dL, whereas Vujovic’s formula excelled for 151–399 mg/dL TG concentrations. All formulas were highly correlated with direct LDL-C levels (P < 0.001). Bland–Altman analysis indicated Vujovic’s formula as the closest match to direct measurement, with a mean bias of −1.42 ± 20.59 mg/dL. Conclusion Vujovic’s formula demonstrated the slightest difference and strong correlation with direct LDL-C measurement, outperforming other formulas. This finding enhances the accuracy of LDL-C assessment and improves CVD risk management in clinical practice.

Keywords

• cholesterol
• lipoproteins
• low-density lipoprotein