The impact of admission cystatin C levels on in-hospital and three-year mortality rates in acute decompensated heart failure.

Background: Although tremendous advances have been made in preventative and therapeutic approaches in heart failure (HF), the hospitalisation and mortality rates for patients with HF is high. The aim of this study was to investigate the association between cystatin C and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and in- and out-of-hospital mortality rates in acute decompensated HF (ADHF).

Methods: Between February 2008 and November 2011, 57 consecutive patients who were admitted with ADHF were included in this prospective study. These patients were clinically followed up every three months by means of visits or telephone interviews. The primary clinical endpoint of this study was any death from heart failure rehospitalisation and/or other causes.

Results: The subjects who died during the in-hospital follow up were younger than the survivors (47.4 ± 17.5 vs 60.8 ± 15.8, p = 0.043). There was a notable correlation between plasma cystatin C and NT-proBNP levels (r = 0.324, p = 0.014) and glomerular filtration rate (GFR) (r = -0.638, p < 0.001). Multivariate logistic regression analysis revealed that only cystatin C level [odds ratio (OR): 12.311, 95% confidence interval (CI): 1.616-93.764, p = 0.015] and age [OR: 0.925, 95% CI: 0.866-0.990, p = 0.023] were linked to in-hospital mortality rate. In the multivariate Cox proportional hazard model, only admission sodium level appeared as a significant independent predictor of death during the 36-month follow up [hazard ratio: 0.937, 95% CI: 0.880-0.996, p = 0.037].

Conclusion: Evaluation of admission cystatin C levels may provide a reliable prediction of in-hospital mortality, compared to estimated GFR or NT-proBNP levels among patients with ADHF. However, in this trial, during long-term follow up, only admission sodium level significantly predicted death.