Table 3. Subgroup analysis of the effect of NT-proBNP levels on in-hospital mortality and length of stay, Lausanne university hospital, 2013–2015.
| First to fourth quintile | Fifth quintile | p-value | |
|---|---|---|---|
| Heart failure | (n = 275) | (n = 199) | |
| In-hospital mortality 1 | |||
| Bivariate | 18 (6.6) | 27 (13.6) | 0.010 |
| Multivariable-adjusted 3 | 1 (ref.) | 1.48 (0.80–2.74) | 0.217 |
| Length of stay (days) 2 | |||
| Bivariate | 14.4 ± 23.1 | 19.0 ± 24.7 | 0.002 |
| Multivariable-adjusted 3 | 14.3 ± 1.4 | 19.1 ± 1.7 | 0.002 |
| Other heart disease | (n = 712) | (n = 139) | |
| In-hospital mortality 1 | |||
| Bivariate | 24 (3.4) | 19 (13.7) | <0.001 |
| Multivariable-adjusted 3 | 1 (ref) | 1.77 (0.93–3.37) | 0.082 |
| Length of stay (days) 2 | |||
| Bivariate | 9.0 ± 10.7 | 20.6 ± 25.8 | <0.001 |
| Multivariable-adjusted 3 | 9.2 ± 0.5 | 19.2 ± 1.2 | <0.001 |
| Pneumonia | (n = 185) | (n = 44) | |
| In-hospital mortality 1 | |||
| Bivariate | 12 (6.5) | 5 (11.4) | 0.267 |
| Multivariable-adjusted 3 | 1 (ref.) | 0.82 (0.23–2.95) | 0.762 |
| Length of stay (days) 2 | |||
| Bivariate | 10.0 ± 10.6 | 15.6 ± 14.2 | 0.002 |
| Multivariable-adjusted 3 | 9.9 ± 0.8 | 16.3 ± 1.7 | <0.001 |
| COPD | (n = 94) | (n = 8) | |
| In-hospital mortality 1 | |||
| Bivariate | 1 (1.1) | 1 (12.5) | 0.151 |
| Multivariable-adjusted 3 | NA | NA | |
| Length of stay (days) 2 | |||
| Bivariate | 11 ± 18.2 | 10.9 ± 11.9 | 0.801 |
| Multivariable-adjusted 3 | NA | NA | |
| Other diagnosis | (n = 1802) | (n = 375) | |
| In-hospital mortality 1 | |||
| Bivariate | 143 (7.9) | 103 (27.5) | <0.001 |
| Multivariable-adjusted 3 | 1 (ref.) | 2.20 (1.68–2.87) | <0.001 |
| Length of stay (days) 2 | |||
| Bivariate | 17.9 ± 31.9 | 22.7 ± 24.0 | <0.001 |
| Multivariable-adjusted 3 | 18.0 ± 0.7 | 22.2 ± 1.6 | <0.001 |
1 expressed as number of patients (percentage)
2 comparisons performed on log-transformed data
3 adjusted for age (continuous), gender, principal diagnoses (heart failure, other heart disease, pneumonia, COPD and other), stage 5 renal failure (yes/no), hospital ward (medicine, surgery, intensive care) and stay in emergency room (yes/no). For in-hospital mortality, results are expressed as rate (bivariate) or as multivariable-adjusted hazard ratio and (95% confidence interval). Between-group comparisons were performed using chi-square (bivariate) or Cox regression (multivariable). For length of stay, results are expressed as average±standard deviation (bivariate) or as multivariable-adjusted average±standard error. Between-group comparisons were performed using student’s t-test (bivariate) or analysis of variance (multivariable).