The predictive value of cardiac troponin T measurements in subjects on regular haemodialysis.
BACKGROUND
Cardiac troponin T (cTnT) is a subunit of the cardiac actin-myosin complex, which leaks into the circulation when myocardial necrosis is present. Detection of cTnT is associated with a poor outcome in patients with unstable angina, and is a useful tool for risk stratification. The value of cTnT determination in patients with renal failure has been questioned, and the specificity of cTnT in this particular group has not been established.


METHODS
In the present study, 94 patients at a single centre were followed prospectively after three determinations of cTNT, at 1-month intervals. The outcome after 12 months was chosen as the end-point. cTnT was measured using both a quantitative chemiluminiscence immunoassay and a qualitative rapid bedside immunoassay on a test strip. The maximum of three measurements was used and was correlated with different parameters and outcome. The following statistical tests were performed: Kaplan-Meier analysis, Cox's proportional regression analysis for measuring survival and logistic regression for analysing factors influencing cTnT.


RESULTS
Forty seven of the 94 patients had a positive cTnT by test strip defined as >0.10 ng/ml. Twenty four patients died in the follow-up period (14 from cardiovascular causes). Twenty of the 24 non-survivors had an increased cTnT by test strip and 23 had increased cTnT by laboratory immunoassay. The outcome analysed by a Cox's proportional regression analysis showed that the factors which influenced survival significantly were cTnT, the presence of ischaemic heart disease, C-reactive protein (CRP) and prealbumin. A logistic multivariate analysis revealed that age and CRP significantly influenced cTnT. A good correlation was found between cTnT determined by test strip and in the laboratory.


CONCLUSIONS
cTnT is elevated in a large number of patients on regular haemodialysis and is a significant independent predictor of outcome. Increased cTnT is significantly predicted by age and CRP.
Stolear
J C
JC
Department of Nephrology, Institut Medico-Chirurgical de Tournai, Belgium.
Georges
B
B
Shita
A
A
Verbeelen
D
D
D000375:Aging / Q000097:blood; D005260:Female; D006801:Humans; D007158:Immunologic Techniques; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000097:blood; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012044:Regression Analysis; D006435:Renal Dialysis; D016019:Survival Analysis; D020107:Troponin T / Q000097:blood*
D020107:Troponin T