title: Monthly reference change value of cardiac troponin in hemodialysis patients as a useful tool for long-term cardiovascular management.
abstract: OBJECTIVE
  Circulating cardiac troponin (cTn) has been identified as a risk factor for cardiovascular and overall mortality in patients undergoing hemodialysis. However, its interpretation remains difficult due to the high prevalence of patients with cTn level beyond the 99th percentile. Determining the cTn reference change value (RCV) may help in assessing a clinically significant change of cTn during regular follow-up of patients. We aimed to determine the long-term RCV of cTn in such patients and to calculate the perdialytic reduction rate of cTn.
  
  
  METHODS
  To calculate RCV, high-sensitivity (hs)-cTnT (Roche), hs-cTnI (Abbott), and cTnI-ultra (Siemens) were determined every month before the midweek dialysis session over a 3-month period in 36 stable hemodialysis patients. cTn was also measured after the midweek dialysis session to calculate the cTn removal rate.
  
  
  RESULTS
  The mean RCV (95% confidence interval) was 22% (18-26) for hs-cTnT versus 53% (34-73) for hs-cTnI versus 65% (45-84) for cTnI-ultra. Log-normal RCV (%) was -19/+25 for hs-cTnT, -33/+96 for hs-cTnI, and -39/+115 for cTnI-ultra. The index of individuality was <0.6 regardless of the cTn assay used. A significantly greater reduction rate was observed for hs-cTnT (48%) than for hs-cTnI (30%, p<0.001) and cTnI-ultra (29%, p<0.05).
  
  
  CONCLUSIONS
  These results underline the need to use the RCV approach rather than cutoff points to identify the critical change in long-term serial cTn levels. In addition, RCV should be determined for each available assay due to significant differences between assays. Removal of cTn during hemodialysis sessions should also be considered if acute coronary syndrome is suspected during a session.
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France; PhyMedExp, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34295 Montpellier Cedex 5, France.
authors.forename: S
authors.initials: S
authors.lastname: Badiou
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France.
authors.forename: A
authors.initials: A
authors.lastname: Boudet
authors.affiliation: Nephrology, GCS HELP Dialysis Center, Montpellier, France; Dialysis Research and Training Institute, Montpellier, France.
authors.forename: H
authors.initials: H
authors.lastname: Leray-Moragues
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France; Dialysis Research and Training Institute, Montpellier, France.
authors.forename: A
authors.initials: A
authors.lastname: Rodriguez
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France; PhyMedExp, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34295 Montpellier Cedex 5, France.
authors.forename: A S
authors.initials: AS
authors.lastname: Bargnoux
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France.
authors.forename: A M
authors.initials: AM
authors.lastname: Dupuy
authors.affiliation: Department of Biochemistry, Montpellier University Hospital, Montpellier, France; PhyMedExp, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34295 Montpellier Cedex 5, France. Electronic address: jp-cristol@chu-montpellier.fr.
authors.forename: J P
authors.initials: JP
authors.lastname: Cristol
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000628:therapy*; D005260:Female; D006801:Humans; D057230:Limit of Detection; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D006435:Renal Dialysis; D014336:Troponin / Q000097:blood*
chemical_list: D014336:Troponin
keywords: Acute coronary syndrome; Cardiovascular risk; Hemodialysis; Hs-troponin; Reference change value