Applicability of Martin-Hopkins formula and comparison with Friedewald formula for estimated low-density lipoprotein cholesterol in e_COR study population

Abstract

Introduction

Low-density lipoprotein cholesterol (LDL) is essential in managing cardiovascular disease risk. Since 1972, the Friedewald formula has been used to estimate LDL concentration, although with some limitations. In 2013, Martin et al. proposed a similar but more accurate formula for calculating LDL.

Aim

To assess the applicability of the new formula, which we have named the Martin-Hopkins formula, in the Portuguese population and compare it with the Friedewald formula using direct LDL.

Methods

Cross-sectional study, including 1689 participants from the e_COR study. We applied the Martin-Hopkins and Friedewald formulas for estimated LDL (LDL-M and LDL-F). The Friedewald formula was not applied in 12 cases due to triglycerides ≥400 mg/dL. Direct LDL was measured and the accepted significance level was p<0.05.

Results

Of the total subjects, 50.2% were male and had a median age of 51 (34) years. LDL-D was 117.0 (44.0) mg/dL, LDL-M was 114.6 (43.7) mg/dL and LDL-F was 113.8 (43.2) mg/dL. The Spearman coefficient (ρ) between LDL-M/LDL-D was 0.987 and between LDL-F/LDL-D was 0.983, p=0.001. This strong correlation was maintained in the group with diabetes (LDL-M/LDL-D ρ=0.987; LDL-F/LDL-D ρ=0.978, p=0.001) and hypertriglyceridemia (LDL-M/LDL-D ρ=0.983; LDL-F/LDL-D ρ=0.982, p=0.001). In terms of agreement, the highest value of κ=0.90 was obtained for LDL-M when LDL-D <100 mg/dL.

Conclusion

The Martin-Hopkins formula performed well and had good applicability, showing superiority in relation to the Friedewald formula, especially for LDL-D values <100 mg/dL, diabetes, and hypertriglyceridemia.