Impact of the Martin/Hopkins modified equation for estimating LDL-C on lipid target attainment in a high risk patient population

Abstract

Objective: To evaluate the Martin/Hopkins equation for estimating LDL-C as target in a population composed of high cardiac risk patients.

Methods: Lipid profile data from patients with TG ≤ 4.52 mmol/L (<400 mg/dl) were used. The high cardiac risk group (N 4150) consisted of patients over 40 years of age that had an A1C level of 6.5% or above and patients with a history of atherosclerotic cardiovascular disease (ASCVD). Comparisons were made between the Martin/Hopkins formula (MH-LDL-C), the Friedewald formula (F-LDL-C), Non-HDL-C and ApoB.

Results: Higher LDL-C values (0.15 mmol/L or 7.3%) were obtained using MH-LDL-C compared to the F-LDL-C. The % within target (%WT) values for F-LDL-C, MH-LDL-C, Non-HDL-C and ApoB were similar when TG levels were ≤ 1.5 mmol/L with a high degree of concordance as measured by the kappa statistic. When compared to F-LDL-C, Non-HDL-C and ApoB showed a profound decrease in the WT value as TG levels increased from normal (67.7%) to intermediate (39.1%) and high levels (20.8%). MH-LDL-C showed an attenuated decrease in the WT value as TG increased from normal (61.4%) intermediate (43.4%) and high levels (32.7%). Concordance with the alternate target parameters was higher for MH-LDL-C than for F-LDL-C when triglycerides levels were increased.

Conclusion: The Martin/Hopkins modified equation for estimating LDL-C is a significant improvement on the decade's old Friedewald formula; however it remains an imperfect tool to estimate the atherogenic load in patients with high TG levels.

Keywords: Diabetes; Estimation of LDL-C; Lipid profile; Martin/Hopkins equation.