Impaired renal function in patients with ischemic and nonischemic chronic heart failure: association with neurohormonal activation and survival

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 ≤.01, for the lowest quartile ≤53 mL/min), and the relative risk for patients with CAD was 1.81 (P = .01 for the lowest quartile ≤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.