© 2016 Lee et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Despite the importance of accurate assessment for low-density lipoprotein cholesterol (LDL-C), the Friedewald formula has primarily been used as a cost-effective method to estimate LDL-C when triglycerides are less than 400 mg/dL. In a recent study, an alternative to the formula was proposed to improve estimation of LDL-C. We evaluated the performance of the novel method versus the Friedewald formula using a sample of 5,642 Korean adults with LDL-C measured by an enzymatic homogeneous assay (LDL-C D ). Friedewald LDL-C (LDL-C F ) was estimated using a fixed factor of 5 for the ratio of triglycerides to very-low-density lipoprotein cholesterol (TG:VLDL-C ratio). However, the novel LDL-C (LDL-C N ) estimates were calculated using the N-strata-specific median TG:VLDL-C ratios, LDL-C 5 and LDL-C 25 from respective ratios derived from our data set, and LDL-C 180 from the 180-cell table reported by the original study. Compared with LDL-C F , each LDL-C N estimate exhibited a significantly higher overall concordance in the NCEP-ATP III guideline classification with LDL-C D (p < 0.001 for each comparison). Overall concordance was 78.2% for LDL-C F , 81.6% for LDL-C 5 , 82.3%for LDL-C 25 , and 82.0% for LDL-C 180 . Compared to LDL-C 5 , LDLC25 significantly but slightly improved overall concordance (p = 0.008). LDL-C 25 and LDL-C 180 provided almost the same overall concordance; however, LDL-C 180 achieved superior improvement in classifying LDL-C < 70 mg/dL compared to the other estimates. In subjects with triglycerides of 200 to 399 mg/dL, each LDL-C N estimate showed a significantly higher concordance than that of LDL-C F (p < 0.001 for each comparison). The novel method offers a significant improvement in LDL-C estimation when compared with the Friedewald formula. However, it requires further modification and validation considering the racial differences as well as the specific character of the applied measuring method.
Lee, J., Jang, S., & Son, H. (2016). Validation of the martin method for estimating low-density lipoprotein cholesterol levels in Korean adults: Findings from the Korea national health and nutrition examination survey, 2009-2011. PLoS ONE, 11(1). https://doi.org/10.1371/journal.pone.0148147