Table 5.
Univariate Cox Regression Analysis for Variables Associated With 30-Day Mortality and Independent Predictors of 30-Day Mortality Determined by Multivariable Cox Regression Analysis in ICU Patients (n = 368)a
| Univariate | Multivariable | |||||
|---|---|---|---|---|---|---|
| Variable | HR | 95% CI | P Value | HR | 95% CI | P Value |
| Age ≥80 y | 5.49 | 2.31–13.03 | <.001 | 6.75 | 2.60–17.50 | <.001 |
| Male sex | 0.71 | 0.30–1.72 | .452 | - | - | - |
| Influenza vaccine | 1.00 | 0.41–2.40 | .992 | - | - | - |
| Pneumococcal vaccine | 0.58 | 0.13–2.47 | .457 | - | - | - |
| Previous inhaled corticosteroids | 2.17 | 0.90–5.24 | .084 | - | - | - |
| Previous systemic corticosteroids | 2.20 | 0.51–9.43 | .290 | - | - | - |
| Antibiotic use in the last week | 1.46 | 0.57–3.76 | .435 | - | - | - |
| Chronic respiratory disease | 2.32 | 0.96–5.60 | .061 | 2.61 | 1.08–6.33 | .033 |
| Chronic cardiac disease | 2.58 | 1.00–6.65 | .050 | - | - | - |
| Chronic renal disease | 3.66 | 1.23–10.88 | .020 | - | - | - |
| Chronic liver disease | 3.46 | 1.02–11.75 | .047 | 8.53 | 2.18–33.48 | .002 |
| Diabetes mellitus | 1.00 | 0.36–2.72 | .993 | - | - | - |
| Chronic neurologic disease | 1.89 | 0.69–5.15 | .216 | - | - | - |
| Previous pneumonia | 0.77 | 0.18–3.32 | .729 | - | - | - |
| Nursing home resident | 1.75 | 0.41–7.53 | .450 | - | - | - |
| Fever | 1.27 | 0.47–3.48 | .637 | - | - | - |
| Deterioration in sensorium | 1.43 | 0.56–3.70 | .456 | - | - | - |
| C-reactive protein ≥15 mg/dL | 0.54 | 0.23–1.27 | .157 | - | - | - |
| Lymphopenia (<724 lymphocytes/mm3) | 2.30 | 0.95–5.55 | .064 | 2.57 | 1.06–6.24 | .037 |
| Pleural effusion | 1.32 | 0.48–3.61 | .586 | - | - | - |
| Acute respiratory distress syndrome | 1.15 | 0.34–3.90 | .825 | - | - | - |
| Acute renal failure | 3.66 | 1.48–9.06 | .005 | 3.52 | 1.38–8.95 | .008 |
| Appropriate empiric antibiotic treatment | 1.62 | 0.22–12.08 | .637 | - | - | - |
| Streptococcus pneumoniae | 1.32 | 0.51–3.41 | .562 | - | - | - |
| Respiratory virus | 0.36 | 0.05–2.70 | .322 | - | - | - |
Data are shown as estimated HRs (95% CIs) of the explanatory variables in the 30-day mortality group. The HR is defined as the ratio of the hazard rates corresponding to the conditions described by 2 levels of an explanatory variable (the hazard rate is the risk of death [ie, the probability of death], given that the patient has survived up to a specific time). The P value is based on the null hypothesis that all HRs relating to an explanatory variable equal unity (no effect).
Abbreviations: HR, hazard ratio; ICU, intensive care unit.
aExcluded 187 patients with septic shock, 11 patients with missing data regarding septic shock, 30 patients who had do-not-resuscitate orders, and 27 with missing data regarding a do-not-resuscitate order.