Figure 4

Association of sequentially measured NT-proCNP concentrations with long-term mortality. (a) Serum amino-terminal pro-C-type natriuretic peptide (NT-proCNP) concentrations are significantly associated with the overall survival of critically ill patients. Survivors have significantly lower serum NT-proCNP levels on admittance to the ICU (P = 0.002) and on day 3 (P = 0.013). Box plot are displayed, where the bold line indicates the median per group, the box represents 50% of the values, and horizontal lines show minimum and maximum values of the calculated non-outlier values; asterisks and open circles indicate outlier values. (b and c) Kaplan-Meier survival curves of ICU patients are displayed, showing increased overall mortality in the long-term follow up of patients with high NT-proCNP levels (on admission > 8 pmol/L, grey) as compared with patients with low NT-proCNP serum concentrations. P-values are given in the figure. (d) Likewise in patients surviving ICU treatment, long-term survivors showed a significant decline of NT-proCNP serum between day 1 and day 3 (P = 0.010).