Novel Biomarkers Assessing Renal Function in Heart Failure: Relation to Inflammatory Status and Cardiac Remodelling

Background: Patients with heart failure (HF) have a significant decline of renal function. We investigate the association between novel biomarkers of renal dysfunction and indices of inflammatory status and cardiac remodeling in patients with HF. Methods: We enrolled 79 consecutive patients with HF and 79 healthy subjects, adjusted for age and sex. Serum levels of neutrophil gelatinase-associated lipocalin (NGAL), cystatin-C, b-type natriuretic peptide (BNP), tumor necrosis factor alpha (TNFα) and matrix metalloproteinase-9 (MMP-9) were measured by ELISA. Creatinine clearance was estimated using Cockcroft-Gault formula (eCcl). Left ventricular ejection fraction was determined by echocardiography. Results: Patients with HF, compared to healthy subjects, had significantly higher NGAL (p=0.007) and cystatin-C levels (p=0.005). In HF patients, NGAL levels were positively correlated with Creatinine levels (r=0.40, p<0.001), TNFa levels (r=0.43, p<0.001), BNP levels (r=0.36, p=0.003), MMP-9 levels (r=0.37, p=0.02) and inversely correlated with left ventricle ejection fraction (r=-0.23, p=0.045). Interestingly, the association between NGAL and MMP-9 levels was independent from confounders such as age, gender, left ventricle ejection fraction, body mass index, TNFα levels, and BNP levels. Moreover, in HF patients, cystatin-C levels were inversely correlated with eCcl (r=-0.21, p=0.04). Cystatin-C levels were not correlated with TNFa, BNP, MMP-9 levels and with left ventricle ejection fraction (p=NS for all). Conclusions: NGAL is associated with left ventricle ejection fraction, and biomarkers of inflammation and cardiac remodeling in patients with HF. These findings highlight a possible common pathogenetic mechanism of renal dysfunction, inflammatory process and cardiac dysfunction in HF.