Table 3.
Multivariable predictors of mortality
| Parameter | Model 1 |
Model 2 |
Model 3 |
Model 4 |
||||
|---|---|---|---|---|---|---|---|---|
| NRI, P-value | 3.0%, P = 0.25 | 14.3%, P = 0.0007 | 14.3%, P = 0.0007 | |||||
| IDI, P-value | 0.13, P = 0.13 | 0.69, P = 0.01 | 0.69, P = 0.01 | |||||
| C-statistic | 0.77 | 0.76 | 0.78 | 0.78 | ||||
| AIC |
2403 |
2402 |
2386 |
2386 |
||||
| |
HR (95% CI) |
P-value |
HR (95% CI) |
P-value |
HR (95% CI) |
P-value |
HR (95% CI) |
P-value |
| Age | 1.67 (1.41–1.97) | <0.0001 | 1.72 (1.45–2.04) | <0.0001 | 1.69 (1.43–1.99) | <0.0001 | 1.69 (1.43–1.99) | <0.0001 |
| Female | 0.66 (0.47–0.93) | 0.02 | 0.66 (0.47–0.94) | 0.02 | 0.61 (0.43–0.86) | 0.01 | 0.61 (0.43–0.86) | 0.01 |
| Diabetes | 0.89 (0.59–1.34) | 0.58 | 0.93 (0.62–1.41) | 0.74 | 0.96 (0.64–1.46) | 0.86 | 0.96 (0.64–1.46) | 0.86 |
| LVEF | 0.76 (0.66–0.87) | <0.0001 | 0.76 (0.66–0.87) | <0.0001 | 0.78 (0.68–0.89) | 0.0003 | 0.78 (0.68–0.89) | 0.0003 |
| Diuretic | 1.32 (0.92–1.90) | 0.13 | 1.31 (0.92–1.89) | 0.14 | 1.27 (0.88–1.83) | 0.20 | 1.27 (0.88–1.83) | 0.20 |
| Beta-blocker | 0.78 (0.55–1.09) | 0.14 | 0.78 (0.55–1.09) | 0.15 | 0.71 (0.51–1.01) | 0.06 | 0.71 (0.51–1.01) | 0.06 |
| Rest SBP | 0.97 (0.88–1.06) | 0.46 | 1.09 (0.93–1.28) | 0.28 | 1.14 (0.97–1.33) | 0.12 | 1.14 (0.97–1.33) | 0.12 |
| Duke treadmill score | 0.94 (0.90–0.97) | 0.0007 | 0.94 (0.90–0.97) | 0.0007 | 0.95 (0.91–0.99) | 0.01 | 0.95 (0.91–0.99) | 0.01 |
| Peak heart rate | 0.86 (0.78–0.94) | 0.002 | 0.85 (0.77–0.94) | 0.001 | 0.87 (0.79–0.96) | 0.004 | 0.87 (0.79–0.96) | 0.004 |
| Heart rate recovery | 0.96 (0.95–0.98) | <0.0001 | 0.96 (0.95–0.98) | <0.0001 | 0.97 (0.95–0.98) | <0.0001 | 0.97 (0.95–0.98) | <0.0001 |
| Smoking | 1.51 (1.03–2.22) | 0.04 | 1.55 (1.05–2.28) | 0.03 | 1.58 (1.08–2.33) | 0.02 | 1.58 (1.08–2.33) | 0.02 |
| Rest-PP | 0.84 (0.70–1.01) | 0.07 | 0.92 (0.76–1.12) | 0.41 | 0.76 (0.63–0.92) | 0.01 | ||
| Exercise-PP | 0.83 (0.76–0.91) | <0.0001 | ||||||
| Reserve-PP | 0.83 (0.76–0.91) | <0.0001 | ||||||
The variables included in model 1 were: cardiovascular risk factors [age (10 year increments), gender, history of diabetes, smoking], medication use (diuretic and beta blocker use), haemodynamics (rest systolic blood pressure, 10 unit increments), exercise stress parameters (peak heart rate, DTS, HRR), and left ventricular ejection fraction (10 unit increments). Models 2, 3, and 4 included all the variables in model 1 and rest-PP, exercise-PP, and reserve-PP (10 unit increments), respectively. NRI and IDI were computed for the same models including events in 3.12 years of follow-up.
NRI, net reclassification improvement; IDI, integrated discrimination improvement; LVEF, left ventricular ejection fraction; SBP, systolic blood pressure.