Association between troponin I levels and mortality in stable hemodialysis patients

Despite modern dialysis methods, the annual mortality in hemodialysis patients is approximately 23%, mainly due to cardiovascular events ( 1 Staffeld C.G. Paslan S.O. Cardiac disease in patients with end stage renal disease. Cardiol Clin. 1995; 13: 209-223 PubMed Google Scholar , 2 United States Renal Data System1994 annual report. Am J Kidney Dis. 1994; 24: 48-56 Google Scholar ). A method to identify which patients would benefit from cardiac evaluation and intervention would be useful. Although elevated levels of creatine kinase and creatine kinase–MB have been reported in renal failure patients without acute coronary events, they do not appear to have prognostic value ( 3 Lee T.H. Goldman L. Serum enzyme assays in the diagnosis of acute myocardial infarction. Recommendations based on a quantitative analysis. Ann Intern Med. 1986; 105: 221-233 Crossref PubMed Scopus (240) Google Scholar , 4 Green T.R. Golper T.A. Swenson R.D. et al. Diagnostic value of creatine kinase and creatine kinase MB isoenzyme in chronic hemodialysis patients a longitudinal study. Clin Nephrol. 1986; 25: 22-27 PubMed Google Scholar , 5 Ma K.W. Brown D.C. Steele B.W. et al. Serum creatine kinase MB isoenzyme activity in long-term hemodialysis patients. Arch Intern Med. 1981; 141: 164-166 Crossref PubMed Scopus (23) Google Scholar , 6 Jaffe A.S. Ritter C. Meltzer V. et al. Unmasking artifactual increases in creatine kinase isoenzymes in patients with renal failure. J Lab Clin Med. 1984; 104: 193-202 PubMed Google Scholar ). Troponin T levels can help in identifying patients who have a poor prognosis ( 7 Dierkes J. Domrose U. Westphal S. et al. Cardiac troponin T predicts mortality in patients with end-stage renal disease. Circulation. 2000; 102: 1964-1969 Crossref PubMed Scopus (242) Google Scholar ), but elevations in these levels have been reported in noncardiac conditions ( 8 Bodor G.S. Survant L. Voss E.M. et al. Cardiac troponin-T composition in normal and regenerating human skeletal muscle. Clin Chem. 1997; 43: 476-484 PubMed Google Scholar ). Troponin I, however, is expressed exclusively in the myocardium ( 9 Adams III, J.E. Abendschein D.R. Jaffe A.S. Biochemical markers of myocardial injury. Is MB creatine kinase the choice for the 1990s?. Circulation. 1993; 88: 750-763 Crossref PubMed Google Scholar , 10 Bodor G.S. Porterfield D. Voss E.M. et al. Cardiac troponin-I is not expressed in fetal and healthy or diseased adult human skeletal muscle tissue. Clin Chem. 1995; 41: 1710-1715 PubMed Google Scholar , 11 Trinquier S. Flecheux O. Bullenger M. et al. Highly specific immunoassay for cardiac troponin I assessed in noninfarct patients with chronic renal failure or severe polytrauma. Clin Chem. 1995; 41: 1675-1676 PubMed Google Scholar ). It was our hypothesis that elevated levels of troponin I might reflect occult myocardial ischemia and identify hemodialysis patients who are at higher risk of 1-year mortality.