Prognostic value of troponin T in hemodialysis patients is independent of comorbidity

Background. Patients on long-term hemodialysis have a high mortality. Vario us clinical and biochemical markers are of prognostic value. Cardiac tropon in T (cTnT) is a sensitive and specific marker for myocardial damage. Asymp tomatic dialysis patients have a high prevalence of cTnT concentrations abo ve the diagnostic threshold for myocardial damage. There is controversy ove r whether this represents a false positive cTnT or an underlying pathology with a poor outcome. It is not known whether cTnT reflects comorbidity in t hese patients. Methods. A cohort of 73 long-term hospital hemodialysis patients had cTnT e stimated once prior to a mid-week dialysis. Samples were analyzed using the second-generation cTnT assay from Boehringer Mannheim on an Elecsys 1010 a nalyzer. The standard diagnostic threshold for myocardial damage of 0.1 ng/ mL was used. A commonly employed measure of comorbidity (Khan) was applied at the time cTnT was measured. Patients were followed for 15 months. Mortal ity was used as the clinical end point. Kaplan-Meier survival analysis was employed and differences between groups were assessed using the Cox-Mantel log-rank test. Results. Of the 73 patients, 20 were positive for cTnT and 53 were negative , at the cut-off of 0.1 ng/mL. At fifteen months, 65% of the positive patie nts were dead, whereas only 15% of the negative patients were dead. Surviva l analysis confirmed that this difference was statistically significant (P < 0.00001), and that the effect of cTnT on survival was independent of como rbidity. Conclusions. There is a high prevalence of positive cTnT in stable hemodial ysis patients. A single estimation of cTnT in this group has significant pr ognostic value, independent of comorbidity.