title: Early diagnosis of acute myocardial infarction in the elderly using more sensitive cardiac troponin assays.
abstract: OBJECTIVE
  To examine the diagnostic accuracy of sensitive cardiac troponin (cTn) assays in elderly patients, since elevated levels with sensitive cTn assays were reported in 20% of elderly patients without acute myocardial infarction (AMI).
  
  
  RESULTS
  In this multi-centre study, we included 1098 consecutive patients presenting with symptoms suggestive of AMI, 406 (37%) were >70 years old. Measurement of three investigational sensitive cTn assays [Roche high-sensitive cTnT (hs-cTnT), Siemens cTnI-Ultra, and Abbott-Architect cTnI) and the standard assay (Roche cTnT) was performed in a blinded fashion. The final diagnosis was adjudicated by two independent cardiologists. Acute myocardial infarction was the adjudicated final diagnosis in 24% of elderly patients. Among elderly patients without AMI, baseline cTn levels were elevated above the 99th percentile in 51% with Roche hs-cTnT, in 17% with Siemens TnI-Ultra, and 13% with Abbott-Architect cTnI. The diagnostic accuracy as quantified by the area under the receiver operating characteristic (ROC) curve (AUC) was significantly greater for the sensitive cTn assays compared with the standard assay (AUC for Roche hs-cTnT, 0.94; Siemens cTnI-Ultra, 0.95; and Abbott-Architect cTnI, 0.95 vs. AUC for the standard assay, 0.90; P < 0.05 for comparisons). The best cut-offs for the sensitive cTn-assays determined by the ROC-curve in elderly patients differed clearly from those in younger patients. Furthermore, the prognostic value regarding 90-day mortality varied among the sensitive cTn assays.
  
  
  CONCLUSIONS
  Sensitive cTn assays have high diagnostic accuracy also in the elderly. Mild elevations are common in elderly non-AMI patients, therefore the optimal cut-off levels are substantially higher in elderly as compared with younger patients. Furthermore, sensitive cTn assays yielded different prognostic value.
authors.affiliation: Department of Internal Medicine, University Hospital, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Miriam
authors.initials: M
authors.lastname: Reiter
authors.forename: Raphael
authors.initials: R
authors.lastname: Twerenbold
authors.forename: Tobias
authors.initials: T
authors.lastname: Reichlin
authors.forename: Philip
authors.initials: P
authors.lastname: Haaf
authors.forename: Frederico
authors.initials: F
authors.lastname: Peter
authors.forename: Julia
authors.initials: J
authors.lastname: Meissner
authors.forename: Willibald
authors.initials: W
authors.lastname: Hochholzer
authors.forename: Claudia
authors.initials: C
authors.lastname: Stelzig
authors.forename: Michael
authors.initials: M
authors.lastname: Freese
authors.forename: Corinna
authors.initials: C
authors.lastname: Heinisch
authors.forename: Tobias
authors.initials: T
authors.lastname: Breidthardt
authors.forename: Heike
authors.initials: H
authors.lastname: Freidank
authors.forename: Katrin
authors.initials: K
authors.lastname: Winkler
authors.forename: Isabel
authors.initials: I
authors.lastname: Campodarve
authors.forename: Joaquim
authors.initials: J
authors.lastname: Gea
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis*; D015588:Observer Variation; D011446:Prospective Studies; D012372:ROC Curve; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
chemical_list: D019210:Troponin I; D020107:Troponin T