title: Non-HDL cholesterol shows improved accuracy for cardiovascular risk score classification compared to direct or calculated LDL cholesterol in a dyslipidemic population.
abstract: BACKGROUND
  Our objective was to evaluate the accuracy of cardiovascular disease (CVD) risk score classification by direct LDL cholesterol (dLDL-C), calculated LDL cholesterol (cLDL-C), and non-HDL cholesterol (non-HDL-C) compared to classification by reference measurement procedures (RMPs) performed at the CDC.
  
  
  METHODS
  We examined 175 individuals, including 138 with CVD or conditions that may affect LDL-C measurement. dLDL-C measurements were performed using Denka, Kyowa, Sekisui, Serotec, Sysmex, UMA, and Wako reagents. cLDL-C was calculated by the Friedewald equation, using each manufacturer's direct HDL-C assay measurements, and total cholesterol and triglyceride measurements by Roche and Siemens (Advia) assays, respectively.
  
  
  RESULTS
  For participants with triglycerides<2.26 mmol/L (<200 mg/dL), the overall misclassification rate for the CVD risk score ranged from 5% to 17% for cLDL-C methods and 8% to 26% for dLDL-C methods when compared to the RMP. Only Wako dLDL-C had fewer misclassifications than its corresponding cLDL-C method (8% vs 17%; P<0.05). Non-HDL-C assays misclassified fewer patients than dLDL-C for 4 of 8 methods (P<0.05). For participants with triglycerides≥2.26 mmol/L (≥200 mg/dL) and<4.52 mmol/L (<400 mg/dL), dLDL-C methods, in general, performed better than cLDL-C methods, and non-HDL-C methods showed better correspondence to the RMP for CVD risk score than either dLDL-C or cLDL-C methods.
  
  
  CONCLUSIONS
  Except for hypertriglyceridemic individuals, 7 of 8 dLDL-C methods failed to show improved CVD risk score classification over the corresponding cLDL-C methods. Non-HDL-C showed overall the best concordance with the RMP for CVD risk score classification of both normal and hypertriglyceridemic individuals.
authors.affiliation: National Institutes of Health, Department of Laboratory Medicine, Bethesda, MD 20892-1508, USA.
authors.forename: Hendrick E
authors.initials: HE
authors.lastname: van Deventer
authors.forename: W Greg
authors.initials: WG
authors.lastname: Miller
authors.forename: Gary L
authors.initials: GL
authors.lastname: Myers
authors.forename: Ikunosuke
authors.initials: I
authors.lastname: Sakurabayashi
authors.forename: Lorin M
authors.initials: LM
authors.lastname: Bachmann
authors.forename: Samuel P
authors.initials: SP
authors.lastname: Caudill
authors.forename: Andrzej
authors.initials: A
authors.lastname: Dziekonski
authors.forename: Selvin
authors.initials: S
authors.lastname: Edwards
authors.forename: Mary M
authors.initials: MM
authors.lastname: Kimberly
authors.forename: William J
authors.initials: WJ
authors.lastname: Korzun
authors.forename: Elizabeth T
authors.initials: ET
authors.lastname: Leary
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Nakajima
authors.forename: Masakazu
authors.initials: M
authors.lastname: Nakamura
authors.forename: Robert D
authors.initials: RD
authors.lastname: Shamburek
authors.forename: George W
authors.initials: GW
authors.lastname: Vetrovec
authors.forename: G Russell
authors.initials: GR
authors.lastname: Warnick
authors.forename: Alan T
authors.initials: AT
authors.lastname: Remaley
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D002318:Cardiovascular Diseases / Q000097:blood / Q000145:classification* / Q000209:etiology; D016022:Case-Control Studies; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D003627:Data Interpretation, Statistical; D050171:Dyslipidemias / Q000097:blood* / Q000150:complications; D005215:Fasting / Q000097:blood; D006801:Humans; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014280:Triglycerides / Q000097:blood*; D014461:Ultracentrifugation
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides