NPPB and heart failure: Plasma NGAL values at presentation of this heart failure cohort were significantly correlated with age (r = 0.27, P < 0.0001), admission hemoglobin levels (r = -0.23, P = 0.0002), admission creatinine values (r = 0.52, P < 0.0001) and baseline creatinine (r = 0.45, P < 0.0001), but not to BNP levels (r = 0.11, P = 0.16), leukocyte count (r = 0.15, P = 0.06), C-reactive protein values (r = 0.11, P = 0.135), body mass index (r = -0.12, P = 0.13) or central venous pressure (r = -0.07, P = 0.49) measured by non-invasive compression sonography.