Prognostic value of serum cardiac troponin I in ambulatory patients with chronic renal failure undergoing long-term hemodialysis - A two-year outcomeanalysis

OBJECTIVES We sought to evaluate the prognostic value of cardiac troponin I (cTnI) in asymptomatic, ambulatory patients with chronic renal failure tre ated with long-term hemodialysis. BACKGROUND Smaller, short-term follow-up studies on this subject have given conflicting results. METHODS A total of 126 ambulatory patients with chronic renal failure treat ed with long-term hemodialysis were followed for two years for all-cause mo rtality, cardiac mortality, all-cause hospital admissions and cardiac hospi tal admissions. Serum cTnI was measured before dialysis at the time of stud y entry. RESULTS One hundred two patients had normal serum levels of cTnI (less than or equal to0.03 ng/ml) and 24 patients had elevated levels (0.015 +/- 0.00 7 vs. 0.053 +/- 0.029 ng/ml, p < 0.0001). No significant difference in all- cause mortality (20 vs. 4 deaths), cardiac mortality (4 vs. 1 death), all-c ause hospital admissions (1.74 +/- 1.72 vs. 1.25 +/- 1.19 admissions/patien t) or cardiac admissions (0.52 +/- 0.89 vs. 0.33 +/- 0.76 admissions/patien t) was present between the patients with normal cTnI levels and those with elevated cTnI levels. Serum cTnI was not significantly different between pa tients who died versus those who survived (0.022 +/- 0.019 vs. 0.022 +/- 0. 021 ng/ml). Serum cTnI was not an independent predictor of all-cause mortal ity, cardiac mortality, all-cause admissions or cardiac admissions. Age (ol der) and serum albumin (lower) were independent predictors of all-cause mor tality, whereas a history of myocardial infarction was an independent predi ctor of cardiac mortality. Serum sodium (lower) was an independent predicto r of all-cause hospital admissions, whereas hypertension and previous myoca rdial infarction were independent predictors of cardiac admissions. The bes t predictors of the time to death were age (older) and serum sodium level ( lower), irrespective of the serum cTnI levels. CONCLUSIONS Cardiac troponin I has a limited role in predicting mortality a nd hospital admissions in asymptomatic patients with chronic renal failure treated with long-term hemodialysis. (C) 2001 by the American College of Ca rdiology.