Increased mortality in hemodialyzed patients with elevated serum troponin T: a one-year outcome study

Abstract

Objectives: To determine the significance of elevated serum troponin T (cTnT) occurring in hemodialysis patients in the absence of clinical evidence of acute coronary ischemia. Design and methods: Twelve-month follow-up of cohort of 172 hemodialyzed patients with known serum cTnT concentration. The cohort consisted of patients undergoing hemodialysis in a hospital unit over a 5-month period, with one to four measurements of cTnT. The main outcome measure was death. Cause of death was determined by autopsy in six patients. Results: Of the 31 deaths, 12 were due to acute coronary disease, 14 were noncoronary, and 5 were undefined. Death rates of patients with cTnT < 0.1, 0.1–0.2, and > 0.2 μg/L were 9.9% (11/111), 32.4% (12/37), and 33.3% (8/24), respectively. The increase in death rate with cTnT ≥ 0.1 μg/L was significant ( p < 0.001) for noncoronary deaths, but not for acute coronary deaths. The risk ratios for noncoronary deaths in the subgroups were: nondiabetics 6.6 (95% CI 1.9–23.6), patients with no coronary artery disease 7.3 (1.6–32.4), patients with no peripheral vascular disease 8.9 (2.0–39.7), and hypertensives 9.0 (1.1–76.5). Significant increase in coronary deaths was seen only in patients without hypertension and those aged ≥ 50 years. The risk ratios for these groups were 9.3 (1.2–74.3) and 3.3 (1.0–10.6), respectively. Conclusions: Serum cTnT is a potential prognostic marker of mortality in hemodialyzed patient, with increase in death from coronary and noncoronary causes.