B-type natriuretic peptide concentrations predict the progression of nondiabetic chronic kidney disease: the Mild-to-Moderate Kidney Disease Study - Spanaus, K S; Kronenberg, F; Ritz, E; Schlapbach, R; Fliser, D; Hersberger, M; Kollerits, B; Konig, P; von Eckardstein, A (Clin Chem, 2007)