title: Low-density lipoprotein particle concentration and size as determined by nuclear magnetic resonance spectroscopy as predictors of cardiovascular disease in women.
abstract: BACKGROUND
  Nuclear magnetic resonance (NMR) offers an alternative, spectroscopic means of quantifying LDL and of measuring LDL particle size.
  
  
  RESULTS
  We conducted a prospective nested case-control study among healthy middle-aged women to assess LDL particle size (NMR) and concentration (NMR) as risk factors for future myocardial infarction, stroke, or death of coronary heart disease. Median baseline levels of LDL particle concentration (NMR) were higher (1597 vs 1404 nmol/L; P= 0.0001) and LDL particle size (NMR) was lower (21.5 vs 21.8 nm; P=0.046) among women who subsequently had cardiovascular events (n=130) than among those who did not (n= 130). Of these 2 factors, LDL particle concentration (NMR) was the stronger predictor (relative risk for the highest compared with the lowest quartile=4.17, 95% CI 1.96-8.87). This compared with a relative risk of 3.11 (95% CI 1.55-6.26) for the ratio of total cholesterol to HDL cholesterol and a relative risk of 5.91 (95% CI 2.65-13.15) for C-reactive protein. The areas under the receiver operating characteristic curves for LDL particle concentration (NMR), total cholesterol to HDL cholesterol ratio, and C-reactive protein were 0.64, 0.64, and 0.66, respectively. LDL particle concentration (NMR) correlated with several traditionally assessed lipid and nonlipid risk factors, and thus adjustment for these tended to attenuate the magnitude of association between LDL particle concentration (NMR) and risk.
  
  
  CONCLUSIONS
  In this cohort, LDL particle concentration measured by NMR spectroscopy was a predictor of future cardiovascular risk. However, the magnitude of predictive value of LDL particle concentration (NMR) was not substantively different from that of the total cholesterol to HDL cholesterol ratio and was less than that of C-reactive protein.
authors.affiliation: Center for Cardiovascular Disease Prevention, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass 02215, USA.
authors.forename: Gavin J
authors.initials: GJ
authors.lastname: Blake
authors.forename: James D
authors.initials: JD
authors.lastname: Otvos
authors.forename: Nader
authors.initials: N
authors.lastname: Rifai
authors.forename: Paul M
authors.initials: PM
authors.lastname: Ridker
mesh_terms: D002097:C-Reactive Protein / Q000032:analysis; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D016022:Case-Control Studies; D003327:Coronary Disease / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008055:Lipids / Q000097:blood; D008077:Lipoproteins, LDL / Q000097:blood* / Q000737:chemistry*; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010316:Particle Size; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology
chemical_list: D008055:Lipids; D008077:Lipoproteins, LDL; D002097:C-Reactive Protein