To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Comparing a novel equatio… - University of Gothenburg, Sweden Till startsida
To content Read more about how we use cookies on

Comparing a novel equation for calculating low-density lipoprotein cholesterol with the Friedewald equation: A VOYAGER analysis

Journal article
Authors M. K. Palmer
P. J. Barter
P. Lundman
S. J. Nicholls
P. P. Toth
Björn W. Karlson
Published in Clinical Biochemistry
Volume 64
Pages 24-29
ISSN 0009-9120
Publication year 2019
Published at Institute of Medicine, Department of Molecular and Clinical Medicine
Pages 24-29
Language en
Keywords Friedewald, Low-density lipoprotein cholesterol, Non-high-density lipoprotein cholesterol, Very-low-, guidelines, management
Subject categories Clinical Laboratory Medicine


Treating elevated low-density lipoprotein cholesterol (LDL-C) to risk-stratified target levels is recommended in several guidelines. Thus, accurate estimation of LDL-C is required. LDL-C is typically calculated using the Friedewald equation: (total cholesterol) - (non-high-density lipoprotein cholesterol [non-HDL-C]) - (triglycerides [TGs]/5). As the equation uses a fixed value equal to 5 as a divisor for TGs, it does not account for inter-individual variability, often resulting in underestimation of risk and potentially undertreatment. It is specifically inapplicable in patients with fasting triglycerides >= 400 mg/dL. A novel method of LDL-C calculation was derived and validated by Martin et al.: (non-HDL-C) - (triglycerides/adjustable factor). This equation uses an adjustable factor, the median TG:very-low-density lipoprotein cholesterol ratio in strata defined by levels of TG and non-HDLC, as divisor for TGs, and the adjustable factor ranging from 3 to 12 has been shown to provide more accurate estimates of LDL-C compared with the Friedewald equation using a direct assay as the gold standard. We used 70,209 baseline and on-treatment lipid values from the VOYAGER meta-analysis database to determine the difference in calculated LDL-C values using the Friedewald and novel equations. In patients with TGs < 400 mg/dL, LDL-C values calculated using the novel equation were plotted against those calculated using the Friedewald equation. The novel equation generally resulted in LDL-C values greater than the Friedewald calculation, with differences increasing with decreasing LDL-C levels; 23% of individuals who reached a LDL-C target of 70 mg/dL with the Friedewald equation did not achieve this target when the novel equation was used to calculate LDL-C; these figures were 8% and 2% for < 100 mg/dL and < 130 mg/dL targets, respectively. In patients with triglycerides >= 400 mg/dL, in whom the Friedewald equation is not valid, lipid values calculated using the novel equation were compared with those obtained by beta-quantification. Values calculated with the novel equation did not appear to be closely related with those calculated by beta-quantification in these patients. In conclusion, the novel equation provides a higher estimation of exact LDL-C values than the Friedewald equation, particularly in patients with low LDL-C levels, which may result in undertreatment of some patients whose LDL-C was calculated using the Friedewald method. However, neither may be suitable for patients with TG >= 400 mg/dL.

Page Manager: Webmaster|Last update: 9/11/2012

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?