Page 110 - Biomarkers for risk stratification and guidance in heart failure

HF-related readmission or mortality, n (%)
90 days 180 days 365 days
50 (16.2) 77 (24.9) 103 (33.3)
1 (1.6) 2 (3.2) 2 (3.2)
Serial NT-proBNP measurements during and early after HF admission.
Multivariate Analysis
Based on the multivariate analysis on clinical risk factors, previous episode of HF, ischemic etiology of HF, age, and mean arterial pressure (MAP) were included in the clinical model. In addition, renal function at 1 month after discharge (eGFR <30 mL/min, 30-60 mL/min, or >60 mL/min) was added to form the reference model. Adding eGFR as a continuous instead of a categoric variable did not change the predictive performance of the reference model.
When adding the NT-proBNP parameters to this reference model, inpatient change in NT-proBNP concentration (decrease below vs above the median), early outpatient change in NT-proBNP (increase vs decrease), and NT-proBNP concentration at 1 month after discharge (above vs below the median) remained independent prognostic markers, whereas the absolute NT-proBNP concentration at discharge dropped out of the model (Table 3).
The final NT-proBNP prognostic model therefore consisted of the reference model plus inpatient change in NT-proBNP concentration, early outpatient change in NT-proBNP, and the absolute NT-proBNP concentration 1 month after discharge.
Model accuracy and discrimination of the NT-proBNP prognostic model for 5 1-year mortality and 1-year HF readmission or mortality are presented in Table
4. Model accuracy and discrimination for HF readmission and mortality reached
a c-statistic of 0.85 (95% CI 0.81-0.90), with excellent calibration (Hosmer-
Lemeshow: P= .77), and had significantly better model performance than models
with 1 NT-proBNP parameter (IDI ranging from 6% to 13% \[P < .001\], improvement
in c-statistic ranging from 0.03 to 0.07 \[P < .05\]; Table 4). For mortality, the same
trend was seen (Table 4).
Table 2. Mortality and Combined End Point of HF Readmission or Mortality of the Overall Population and According to the composite NT-proBNP Score
Outcome
Mortality, n (%)
90 days 180 days 365 days
Total Group (n = 309)
16 (5.2) 32 (10.4) 55 (17.8)
Group 1: 0 Points (n= 62)
0 (0) 0 (0) 0 (0)
Group 2: 1 Point (n= 94)
2 (2.1) 5 (5.3) 9 (9.6)
8 (8.5) 14 (14.9) 21 (22.3)
Group 3: 2 Points (n= 83)
4 (4.8) 10 (12.0) 17 (20.5)
14 (16.9) 21 (25.3) 27 (32.5)
Group 4: 3 Points (n= 70)
10 (14.3) 17 (24.3) 29 (41.4)
27 (38.6) 40 (57.1) 53 (75.7)
P Value
.001 <.001 <.001
<.001 <.001 <.001
Abbreviations as in Table 1.
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