The EPIC-Norfolk Study
Value of low-density lipoprotein particle number and size as predictors of coronary artery disease in apparently healthy men and women: the EPIC-Norfolk Prospective Population Study.
Journal of the American College of Cardiology 2006 ; 49: 547-53.
El Harchaoui K, van der Steeg WA, Stroes ES, Kuivenhoven JA, Otvos JD, Wareham NJ, Hutten BA, Kastelein JJ, Khaw KT, and Boekholdt SM
DOI : 10.1016/j.jacc.2006.09.043
PubMed ID : 17276177
PMCID : 0
Abstract
We assessed relations of low-density lipoprotein (LDL) particle number (LDL-P) and LDL particle size as measured by nuclear magnetic resonance spectroscopy with LDL cholesterol (LDL-C) and the risk of future coronary artery disease (CAD).
Whereas LDL-C is an established risk factor for CAD, its discriminative power is limited. Measuring LDL-P and size may have stronger associations with CAD than LDL-C.
A nested case-control study was performed in the prospective EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk study, which comprises 25,663 subjects. Cases (n = 1,003) were individuals who developed CAD during 6 year follow-up. Control subjects (n = 1,885) were matched for age, gender, and enrollment time. Odds ratios (ORs) for future CAD were calculated, and we also evaluated whether LDL-P could improve the Framingham risk score (FRS) to predict CAD.
In univariate analyses, LDL-P (OR 2.00, 95% confidence interval [CI] 1.58 to 2.59) and non-high-density lipoprotein cholesterol (non-HDL-C) (OR 2.14, 95% CI 1.69 to 2.69) were more closely associated with CAD than LDL-C (OR 1.73, 95% CI 1.37 to 2.18). The additional value of LDL-P was lost after adjustment for HDL-C and triglyceride levels. Whereas LDL size was inversely related to CAD (OR 0.60, 95% CI 0.47 to 0.76), this relation was abolished upon adjustment for LDL-P. In a model adjusted for the FRS, LDL-P retained its association with CAD (p for trend 0.02).
In this large study of individuals with moderately elevated LDL-C, LDL-P was related to CAD on top of FRS as well as after adjusting for LDL-C. The additional value of LDL-P was comparable to non-HDL-C, and it was abolished after adjusting for triglycerides and HDL-C.