title: Non-HDL-cholesterol as valid surrogate to apolipoprotein B100 measurement in diabetes: Discriminant Ratio and unbiased equivalence.
abstract: BACKGROUND
  Apolipoprotein B100 (apoB) is a superior indicator of CV risk than total or LDL-C. Non-HDL-C represents a simple surrogate for apoB in hypertriglyceridemic and/or T2DM patients. ApoB and non-HDL-C show high correlation, although the degree of mutual concordance remains debated in CV risk evaluation.
  
  
  OBJECTIVE
  We used the Discriminant Ratio (DR) methodology to compare the performance of non-HDL-C with that of apoB to rank diabetic patients according to dyslipidemia and to establish the underlying relationship between these variables taking measurement noise and intra-/intersubject variation into account, and to derive an unbiased equivalence equation.
  
  
  METHODS
  Fasting total C, HDL-C, apoB and triglycerides were measured in 45 diabetic patients. The DR of the underlying between-subject standard deviation (SD) to the within-subject SD was calculated from duplicates. Correlation coefficients between pairs were adjusted to include an estimate of the underlying correlation.
  
  
  RESULTS
  Mean values [day 1 (1SD)] were 143 (36) mg/dl (non-HDL-C) and 98 (24) mg/dl (apoB). The DR's of both parameters were similar (1.76 and 1.83) (p = 0.83). Pearson's product-moment correlation coefficient between tests was very high (0.94), reaching unity (1.00) after attenuation adjustment. The unbiased equation of equivalence relating apoB to non-HDL-C had a slope of 0.65 and an intercept of 6.3 mg/dl.
  
  
  CONCLUSIONS
  The discrimination power of non-HDL-C is similar to that of apoB to rank diabetic patients according to atherogenic cholesterol and lipoprotein burden. Since true correlation between variables reached unity, non-HDL-C may provide not only a metabolic surrogate but also a candidate biometrical equivalent to apoB, as non-HDL-C calculation is readily available.
authors.affiliation: Endocrinology and Nutrition Unit, Université catholique de Louvain, 10 Avenue Hippocrate, Brussels (1200), Belgium. michel.hermans@diab.ucl.ac.be
authors.forename: Michel P
authors.initials: MP
authors.lastname: Hermans
authors.forename: Frank M
authors.initials: FM
authors.lastname: Sacks
authors.forename: Sylvie A
authors.initials: SA
authors.lastname: Ahn
authors.forename: Michel F
authors.initials: MF
authors.lastname: Rousseau
mesh_terms: D000328:Adult; D000368:Aged; D053299:Apolipoprotein B-100 / Q000097:blood*; D001530:Belgium; D015982:Bias; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology*; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D016002:Discriminant Analysis; D050171:Dyslipidemias / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D053299:Apolipoprotein B-100; D015415:Biomarkers; D008076:Cholesterol, HDL; D014280:Triglycerides; D002784:Cholesterol