title: High sensitivity troponin T in acute medicine; more questions than answers?
abstract: BACKGROUND
  Troponin testing in acute medicine is routine. The introduction of a high sensitivity assay (hs Tn T) has created uncertainty regarding the clinical significance of 'abnormal' troponin T levels. The previous assay could not detect troponin levels <30 ng/l.
  
  
  OBJECTIVE
  To characterize those with a hs Tn T ≥14 ng/l. Prospective cohort study of consecutive admissions to an acute medical unit.
  
  
  RESULTS
  Troponin was measured in 564 consecutive patients (∼50% of all admissions) over 1 month; was ≥14 ng/l in 224 (40%) of which 220 patients had demographic data for this analysis. Median (inter-quartile range) peak troponin was 47.5 ng/l (24-130) and 36% had a Tn T between 14 and 30 ng/l. Mean [standard deviation (SD)] age was 72 (12) years and 57% were male. Only 44 patients (20%) had an acute myocardial infarction, reflecting the increased sensitivity but reduced specificity of the assay. Prognosis was poor with 31% mortality at 1 year. Over a mean (SD) follow-up of 648 (61) days, there were 87 deaths (40%). Those with a primary non-cardiac diagnosis (n = 126) had poorer survival than those with a primary cardiac diagnosis (n = 94). Troponin elevation related to sepsis conferred a very poor prognosis with 24 deaths (70%) over the follow-up period.
  
  
  CONCLUSIONS
  Elevated hs Tn T is very common in acute medicine, but myocardial infarction as an explanation is uncommon. Overall, the prognosis is poor with a tendency to worse outcomes in those with a primary 'non-cardiac' diagnosis.
authors.affiliation: Department of Cardiology, Monklands Hospital, Monkscourt Avenue, Airdrie, ML6 0JS, Glasgow. colinjamespetrie@yahoo.co.uk.
authors.forename: C J
authors.initials: CJ
authors.lastname: Petrie
authors.forename: R A P
authors.initials: RA
authors.lastname: Weir
authors.forename: M S
authors.initials: MS
authors.lastname: Anwar
authors.forename: M A
authors.initials: MA
authors.lastname: Ali
authors.forename: M
authors.initials: M
authors.lastname: Kerr
authors.forename: J A
authors.initials: JA
authors.lastname: Abed
mesh_terms: D000208:Acute Disease; D000368:Aged; D002637:Chest Pain / Q000209:etiology; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000209:etiology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D020107:Troponin T / Q000378:metabolism*
chemical_list: D020107:Troponin T