Table 2 Factors significantly associated in univariate analyses with mortality within 90 days of hospital discharge in the derivation cohort (n = 1117)
FactorsOR (95% CI)p Value
Host-related
    Baseline functional status (continuous)*1.09 (1.07 to 1.11)<0.001
    Baseline functional status*
        16–30 vs 154.86 (1.36 to 17.34)0.02
        >30 vs 1522.53 (6.79 to 74.70)<0.001
    Age (years)1.06 (1.04 to 1.09)<0.001
    Age >75 years3.33 (1.84 to 6.03)<0.001
    Male vs female1.96 (1.02 to 3.77)0.04
    Charlson index
        1 vs 03.05 (1.09 to 8.54)0.03
        2 vs 06.21 (2.24 to 17.19)<0.001
        ⩾3 vs 012.39 (4.55 to 33.69)<0.001
Severity of illness on admission
    CURB score†
        1 vs 01.97 (0.92 to 4.22)0.08
        >1 vs 03.91 (1.83 to 8.37)<0.001
    Bilateral or multilobar radiographic involvement1.61 (0.90 to 2.89)0.11
Process of care
    Appropriate antibiotic0.93 (0.33 to 2.64)0.89
    Antibiotics within 8 h0.82 (0.38 to 1.77)0.60
    Antibiotics prior to admission1.22 (0.65 to 2.27)0.54
    Mechanical ventilation‡––
Length of stay (days)
    Length of stay (days)1.05 (1.00 to 1.10)0.06
    >3 vs ⩽31.70 (0.98 to 2.94)0.06
In-hospital evolution
    Treatment failure2 (0.98 to 4.09)0.06
    Septic shock0.56 (0.08 to 4.17)0.57
Number of instability criteria on discharge
    ⩾1 vs 01.70 (0.99 to 2.93)0.06
Causal microorganism§
    Streptococcus pneumoniaeReference
    Atypical bacterial or virus pathogens0.48 (0.13 to 1.73)0.26
    Mixed infections0.20 (0.03 to 1.56)0.13
    Others1.75 (0.47 to 6.52)0.40
    Unknown1.35 (0.69 to 2.64)0.38

  • Treatment failure and instability criteria on discharge are defined in text. Each factor was examined individually.

  • *Baseline functional status was measured by the Katz index (n = 1036); functional status range 15–52 (excellent functional status, 15). Baseline functional status was analysed as continuous and categorical variable separately.

  • †Severity of illness on admission was assessed with CURB score (Confusion, Urea nitrogen, Respiratory rate, Blood pressure).

  • ‡No deaths within 90 days of discharge were recorded for patients with mechanical ventilation during hospitalisation.

  • §In the univariate analyses for causal microorganisms, the Streptococcus pneumoniae category was considered as the reference group.

  • OR, odds ratio; 95% CI, 95% confidence interval.