Measurement of the Red Blood Cell Distribution Width Improves the Risk Prediction in Cardiac Resynchronization Therapy
Table 5
Multivariable Cox regression analysis 2 of the 5-year survival with validation, calibration, and reclassification.
Basic model with RDW + NT-proBNP
Basic model + RDW
Basic model
Basic model + NT-proBNP
Basic model with NT-proBNP + RDW
Cox regression
HR of RDW
2.42 (1.22–4.76)
2.07 (1.38–5.29)
2.42 (1.22–4.76)
(RDW)
0.01
0.004
0.01
HR of NT-proBNP
1.88 (0.95–3.69)
2.21 (1.13–4.33)
1.88 (0.95–3.69)
(NT-proBNP)
0.06
0.02
0.06
Validation
Overall
46.08
43.52
33.90
39.10
46.08
(overall)
<0.0001
<0.0001
<0.0001
<0.0001
<0.0001
(changes)
0.05
0.002
0.01
0.006
Calibration
HL test
4.65
1.78
11.75
4.71
4.65
(HL test)
0.79
0.98
0.16
0.78
0.79
Performance
Brier score
0.18
0.18
0.19
0.19
0.18
Nagelkerke’s
0.34
0.32
0.25
0.29
0.34
Reclassification
-statistics
0.80 (0.72–0.87)
0.78 (0.70–0.85)
0.74 (0.66–0.82)
0.76 (0.68–0.84)
0.80 (0.72–0.87)
(-statistics)
0.39
0.20
0.29
0.11
NRI (95% CI)
0.24 (–0.03–0.34)
0.64 (0.33–0.95)
0.54 (0.23–0.84)
0.64 (0.33–0.95)
(NRI)
0.19
<0.0001
0.0005
<0.0001
IDI (95% CI)
0.01 (–0.01–0.03)
0.05 (0.01–0.09)
0.03 (−0.00–0.06)
0.04 (0.01–0.07)
(IDI)
0.18
0.004
0.05
0.01
The basic multivariable Cox regression model included age, male gender, NYHA class III/IV, LBBB, beta-blocker therapy, diabetes mellitus, and creatinine > 88.5 μmol/L. The RDW > 13.35% and NT-proBNP > 1975 pg/mL were adjusted separately to the basic model in a forward stepwise manner. The final common model included all variables. HR = hazard ratio; = chi squared; HL test = Hosmer-Lemeshow test; 95% CI = 95% confidence interval; -statistics = overall areas under the curve, assessed by the DeLong test; NRI = net reclassification improvement; IDI = integrated discrimination improvement. NT-proBNP = N-terminal pro-B-type natriuretic peptide; RDW = red blood cell distribution width.
