title: Evaluation of a new homogenous method for detection of small dense LDL cholesterol: comparison with the LDL cholesterol profile obtained by density gradient ultracentrifugation.
abstract: BACKGROUND
  Small, dense LDL (sdLDL) are highly atherogenic, and evidence indicates that sdLDL are useful predictors of cardiovascular disease. We evaluated a homogeneous method for the quantitative determination of sdLDL cholesterol (sdLDL-C) and compared it to the LDL-cholesterol profile obtained by density gradient ultracentrifugation (DGUC).
  
  
  METHODS
  sdLDL-C was measured in plasma and in lipoprotein fractions obtained by DGUC using the sdLDL-EX "Seiken" kit.
  
  
  RESULTS
  sdLDL-C was only present in dense or intermediate LDL fractions obtained by DGUC. Plasma sdLDL-C levels were inversely corelated to the LDL relative floatation rate. The proportion of LDL-C that is sdLDL-C increases as a function of LDL density from a median of 19% for very buoyant LDL to 91% for very dense LDL particles. Plasma sdLDL-C level was significantly correlated with plasma triglyceride (TG) (n=840, r(s)=0.710, p<0.001). Among subjects with plasma TG>150 mg/dl, 75% had sdLDL-C>30 mg/dl, whereas among those with TG ≤ 150 mg/dl, only 17% had sdLDL-C>30 mg/dl.
  
  
  CONCLUSIONS
  This precise and fully automated method for measuring plasma levels of sdLDL-C will allow the analysis of large number of samples in routine laboratories which will facilitate the evaluation of the clinical usefulness of sdLDL as a risk factor for CHD.
authors.affiliation: Northwest Lipid Metabolism and Diabetes Research Laboratories, Department of Medicine, University of Washington, Seattle, WA 98109-4517, USA.
authors.forename: John J
authors.initials: JJ
authors.lastname: Albers
authors.forename: Hal
authors.initials: H
authors.lastname: Kennedy
authors.forename: Santica M
authors.initials: SM
authors.lastname: Marcovina
mesh_terms: D008078:Cholesterol, LDL / Q000097:blood*; D006801:Humans; D015203:Reproducibility of Results; D014461:Ultracentrifugation / Q000379:methods*
chemical_list: D008078:Cholesterol, LDL