Does the Sampson equation improve the accuracy of LDL-C estimation compared to Friedewald and Martin equations, particularly at high and low LDL-C levels and varying triglyceride levels?
The Sampson equation provides more accurate LDL-C estimation than the Friedewald and Martin equations, particularly in patients with elevated triglycerides and at extreme LDL-C clinical decision cut-points.
New more effective lipid-lowering therapies have made it important to accurately determine Low-density lipoprotein-cholesterol (LDL-C) at both high and low levels. LDL-C was measured by the β-quantification reference method (BQ) (N = 40,346) and compared to Friedewald (F-LDL-C), Martin (M-LDL-C), extended Martin (eM-LDL-C) and Sampson (S-LDL-C) equations by regression analysis, error-grid analysis, and concordance with the BQ method for classification into different LDL-C treatment intervals. For triglycerides (TG) 400 mg/dL not only had the least analytical errors but also the lowest frequency of clinically relevant errors at the low (190 mg/dL) LDL-C cut-points (S-LDL-C: 13.5%, F-LDL-C: 23.0%, M-LDL-C: 20.5%) and eM-LDL-C: 20.0%) equations. The S-LDL-C equation also had the best overall concordance to the BQ reference method for classifying patients into different LDL-C treatment intervals. The S-LDL-C equation is both more analytically accurate than alternative equations and results in less clinically relevant errors at high and low LDL-C levels.
Sampson et al. (Tue,) studied this question.