title: Elevated cardiac troponin T in predialysis patients is associated with inflammation and predicts mortality.
abstract: OBJECTIVE
  Cardiac troponin T (cTnT) is a highly sensitive and specific marker of myocardial damage. It has been shown that elevated serum concentrations of cTnT in haemodialysis (HD) patients are associated with poor prognostic outcome. The aim of the present study was to investigate the predictive value of cTnT in samples from predialysis patients and to investigate associations between cTnT and inflammatory markers, such as C-reactive protein (CRP) and interleukin-6 (IL-6).
  
  
  METHODS
  Cohort, follow-up study.
  
  
  METHODS
  Huddinge University Hospital, Sweden.
  
  
  METHODS
  A total of 115 (62% males, 28% diabetic patients) end-stage renal disease (ESRD) patients (52 +/- 1 years), of which 29% had cardiovascular disease (CVD), were studied shortly before the onset of dialysis therapy. Sixty-four patients started peritoneal dialysis (PD) as renal replacement therapy, whilst 49 started HD during the follow-up.
  
  
  METHODS
  The cTnT was analysed with the third generation TnT assay on Elecsys 2010. The prognostic value was calculated for cTnT, IL-6, age, CVD, malnutrition, diabetes mellitus (DM) and gender. Survival analyses were made with Kaplan-Meier and Cox regression analyses, with all-cause mortality as the clinical end point (mean follow-up period 2.7 +/- 0.1 years).
  
  
  RESULTS
  Significant correlations were found between cTnT and CKMB (rho = 0.52, P < 0.0001), IL-6 (rho = 0.23, P < 0.05), CRP (rho = 0.30, P < 0.05), and serum albumin (rho = -0.31, P < 0.001), respectively. Diabetic patients had higher median serum cTnT level (0.09 microg L-1; range <0.01-0.51 vs. 0.04 microg L-1; range <0.01-0.67 microg L-1; P < 0.005) compared with nondiabetic patients. Likewise, patients with CVD had a significantly higher median level (0.08 microg L-1; range <0.01-0.67 microg L-1 vs. 0.04 microg L-1; range <0.01-0.61 microg L-1; P < 0.01) of cTnT compared with patients without CVD. Patients with cTnT > or =0.10 microg L-1 had a higher cumulative mortality rate than patients with cTnT < 0.10 microg L-1 (chi2 = 7.04; P < 0.01). Whilst age, CVD, malnutrition, DM, IL-6, cTnT and male gender were associated with poor outcome in the univariate analysis, only DM (P < 0.05) and cTnT (P < 0.05) were independently associated with mortality in a multivariate analysis.
  
  
  CONCLUSIONS
  The present study demonstrates that serum concentrations of cTnT > or =0.10 microg L-1 is a significant predictor of mortality in patients starting dialysis. Moreover, the positive correlations between cTnT and IL-6, and CRP, respectively, suggest an association between inflammation and cTnT levels. Finally, the results of the present study suggest that cTnT is an independent predictor of mortality in ESRD patients starting dialysis.
authors.affiliation: Division of Clinical Chemistry, Department of Medical Laboratory Sciences and Technology, Karolinska Institutet at Huddinge University Hospital, Stockholm, Sweden. christian.lowbeer@medilab.se
authors.forename: C
authors.initials: C
authors.lastname: Löwbeer
authors.forename: P
authors.initials: P
authors.lastname: Stenvinkel
authors.forename: R
authors.initials: R
authors.lastname: Pecoits-Filho
authors.forename: O
authors.initials: O
authors.lastname: Heimbürger
authors.forename: B
authors.initials: B
authors.lastname: Lindholm
authors.forename: S A
authors.initials: SA
authors.lastname: Gustafsson
authors.forename: A
authors.initials: A
authors.lastname: Seeberger
mesh_terms: D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis; D009202:Cardiomyopathies / Q000097:blood / Q000401:mortality; D015331:Cohort Studies; D003928:Diabetic Nephropathies / Q000097:blood / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D007676:Kidney Failure, Chronic / Q000097:blood / Q000401:mortality* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D006435:Renal Dialysis / Q000401:mortality*; D015996:Survival Rate; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D020107:Troponin T; D002097:C-Reactive Protein