Background: Renal dysfunction is a strong predictor of mortality in chronic heart failure (CHF). Most patients with CHF have atherosclerotic vascular disease, and several authors have suggested that impaired renal function is only a marker of advanced atherosclerosis. We compared renal function in patients with ischemic and nonischemic CHF and examined associations with prognosis and extent of neurohormonal activation.
Methods: In a large survival study (1906 patients), patients with documented coronary artery disease (CAD, n = 995), were compared with patients with idiopathic dilated cardiomyopathy (IDC, n = 429). In a smaller substudy, plasma neurohormones were determined in 270 patients and 37 patients (CAD and IDC, respectively). All patients had advanced CHF (New York Heart Association functional class III-IV). At baseline, the mean patient age was 64 +/- 10 years, and the mean left ventricular ejection fraction was 0.26 +/- 0.08. The baseline glomerular filtration rate was calculated with the Cockcroft-Gault equation (GFRc).
Results: GFRc was a strong predictor for mortality in both groups on multivariate analysis. The relative risk was 3.04 for patients with IDC (P < or =.01, for the lowest quartile < or =53 mL/min), and the relative risk for patients with CAD was 1.81 (P =.01 for the lowest quartile < or =42 mL/min). Plasma neurohormones showed a relation with GFRc in both groups.
Conclusions: GFRc is related to survival and plasma neurohormones in both patient groups. In patients with IDC, this association appears to be at least as strong as in patients with CAD.