Logistic regression model for the risk associated with 90 day post-discharge mortality
| OR (95% CI) | p-value | |
| Age years | 1.037 (1.029–1.046) | 0.0001 |
| Charlson Comorbidity Index points | 1.128 (1.074– 1.185) | 0.0001 |
| Diabetes | 0.661 (0.531–0.822) | 0.0002 |
| Respiratory acidosis | ||
| Mild versus normal | 1.187 (0.957–1.472) | 0.0160 |
| Severe versus normal | 1.858 (1.312–2.632) | |
| Ventilatory support: yes | 2.147 (1.811–2.542) | 0.0001 |
| Respiratory specialists per 1000 beds | 0.995 (0.989–0.999) | 0.0269 |
| Previous admission (one or more) | 1.622 (1.297–2.030) | 0.0001 |
N=15 191. Respiratory acidosis is categorised as: severe, pH <7.25; mild, pH 7.25–7.35; normal, pH >7.35. Results are from a random effects model adjusting for country.