title: Testosterone and cardiometabolic risk in the general population - the impact of measurement method on risk associations: a comparative study between immunoassay and mass spectrometry.
abstract: OBJECTIVE
  Low total testosterone (TT) serum concentrations in men have been associated with various cardiometabolic risk factors. But given error-prone immunoassays used for TT assessment, upcoming mass spectrometry methods question the validity of these risk associations. Thus, we performed the first comparative study quantifying potential differences in the association of TT with cardiometabolic risk factors between the two methods.
  
  
  METHODS
  We used data from 1512 men aged 20-81 years, recruited for the cross-sectional population-based Study of Health in Pomerania (SHIP), Germany. TT concentrations were repeatedly measured by chemiluminescent immunoassay (CLIA, Immulite 2500) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). We tested for significant differences between coefficients from CLIA- and LC-MS/MS-based multiple linear regression models associating TT with major cardiometabolic risk factors including adiposity, lipid metabolism, blood pressure, diabetic status, and inflammation.
  
  
  RESULTS
  TT measurements by CLIA and LCMS/MS yielded a pearson correlation coefficient of 0.84. only three of the ten tested associations for tt with cardiometabolic risk factor showed significant differences between the two measurement methods: in comparison to LC-MS/MS, CLIA-based TT assessment significantly underestimated risk associations of TT with waist circumference (β: -0.54 vs -0.63), BMI (β: -0.19 vs -0.22), and serum glucose levels (β: -0.006 vs -0.008).
  
  
  CONCLUSIONS
  In this comparative study, the CLIA platform showed a reasonable measurement error and yielded comparable risk associations, providing little support to measure TT concentrations in men from the general population exclusively by LC-MS/MS.
authors.affiliation: Institute of Clinical Chemistry and Laboratory Medicine.
authors.forename: Robin
authors.initials: R
authors.lastname: Haring
authors.forename: Sebastian E
authors.initials: SE
authors.lastname: Baumeister
authors.forename: Matthias
authors.initials: M
authors.lastname: Nauck
authors.forename: Henry
authors.initials: H
authors.lastname: Völzke
authors.forename: Brian G
authors.initials: BG
authors.lastname: Keevil
authors.forename: Georg
authors.initials: G
authors.lastname: Brabant
authors.forename: Henri
authors.initials: H
authors.lastname: Wallaschofski
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology*; D002853:Chromatography, Liquid / Q000379:methods / Q000592:standards; D003430:Cross-Sectional Studies; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007118:Immunoassay / Q000379:methods* / Q000592:standards; D008297:Male; D013058:Mass Spectrometry / Q000379:methods* / Q000592:standards; D008659:Metabolic Diseases / Q000097:blood / Q000453:epidemiology*; D008875:Middle Aged; D015203:Reproducibility of Results; D012307:Risk Factors; D013739:Testosterone / Q000032:analysis* / Q000097:blood / Q000172:deficiency; D055815:Young Adult
chemical_list: D013739:Testosterone