title: What have we learnt about high-density lipoprotein cholesterol measurements during 32 years? Experiences in Finland 1980-2012.
abstract: BACKGROUND
  High-density lipoprotein cholesterol (HDL-C) is important in risk assessment for cardiovascular disease or metabolic syndrome; however, different direct HDL-C assays may lead to erroneous risk estimates and potentially misclassify people.
  
  
  METHODS
  Data for 30-year HDL-C trends in Finland were obtained from the national FINRISK surveys during 1982-2012 (n=45766) taking into account biases from three external quality assessment programs (EQA). We also compared two different direct HDL-C and turbidimetric apolipoprotein A-I methods using 413 fresh serum samples.
  
  
  RESULTS
  HDL-C concentrations in the Finnish population were on average 1.33 (±0.04) mmol/l for men and 1.62 (±0.05) mmol/l for women after bias-correction. Positive HDL-C trends were observed for both sexes with original data, but trends disappeared after bias-correction. Comparison of two direct HDL-C methods demonstrated concentration-dependent difference. When HDL-C concentrations were <1.0 mmol/l, the mean bias was -12.0% (95% CI -13.5 to -10.0) whereas HDL-C concentrations >1.55 mmol/l showed mean bias of 9.0% (95% CI 7.0-10.5).
  
  
  CONCLUSIONS
  Accurate reporting of HDL-C concentrations at the population level requires proper and regular attendance to reliable EQA programs. We found evidence for a concentration-dependent difference between some direct HDL-C methods, which may cause misclassification of people in cardiovascular risk assessment.
authors.affiliation: Department of Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland. jaana.leiviska@thl.fi
authors.forename: Jaana
authors.initials: J
authors.lastname: Leiviskä
authors.forename: Jouko
authors.initials: J
authors.lastname: Sundvall
authors.forename: Georg
authors.initials: G
authors.lastname: Alfthan
authors.forename: Riitta
authors.initials: R
authors.lastname: Tähtelä
authors.forename: Veikko
authors.initials: V
authors.lastname: Salomaa
authors.forename: Matti
authors.initials: M
authors.lastname: Jauhiainen
authors.forename: Erkki
authors.initials: E
authors.lastname: Vartiainen
mesh_terms: D000328:Adult; D000368:Aged; D016632:Apolipoprotein A-I / Q000097:blood*; D002318:Cardiovascular Diseases / Q000097:blood / Q000175:diagnosis; D008076:Cholesterol, HDL / Q000097:blood*; D057075:Enzyme Assays / Q000592:standards* / Q000706:statistics & numerical data; D005260:Female; D005387:Finland; D006306:Health Surveys; D006801:Humans; D007118:Immunoassay / Q000592:standards* / Q000706:statistics & numerical data; D008137:Longitudinal Studies; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000175:diagnosis; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry / Q000592:standards* / Q000706:statistics & numerical data; D011786:Quality Control; D012306:Risk
chemical_list: D016632:Apolipoprotein A-I; D008076:Cholesterol, HDL