Table 1. Univariate analysis of factors determining outcomea.
| No. patients (%) | Odds ratio (95% CI)b | p value | |
|---|---|---|---|
| Patient characteristics | |||
| Male | 82 (58) | 1.5 (0.7 to 3.1) | 0.30 |
| Age >67 years | 75 (53) | 1.0 (0.5 to 2.1) | 0.98 |
| Underlying diseases | |||
| COPD | 11 (8) | 0.8 (0.2 to 3.1) | 0.73 |
| Diabetes mellitus | 16 (11) | 1.0 (0.3 to 3.0) | 0.95 |
| Renal insufficiency | 3 (2) | 1.1 (0.1 to 12.1) | 0.96 |
| Cardiac disease | 48 (34) | 1.0 (0.5 to 2.0) | 0.90 |
| Cancer | 10 (7) | 0.5 (0.1 to 2.5) | 0.41 |
| Immunosuppressive medicationd | 11 (8) | 1.9 (0.5 to 6.5) | 0.52 |
| Smokingc | 65 (48) | 2.4 (1.2 to 5.1) | 0.02 |
| Alcohol intakec | 26 (59) | 3.7 (0.8 to 15.8) | 0.08 |
| Symptoms | |||
| Fever | 119 (84) | 0.8 (0.3 to 2.0) | 0.63 |
| Myalgia | 31 (22) | 0.6 (0.2 to 1.4) | 0.21 |
| Headache | 36 (26) | 0.6 (0.3 to 1.5) | 0.30 |
| Cough | 97 (69) | 1.0 (0.5 to 2.2) | 0.99 |
| Dyspnea | 79 (56) | 2.6 (1.2 to 5.5) | 0.01 |
| Diarrhea | 25 (18) | 1.3 (0.5 to 3.1) | 0.63 |
| Confusion | 31 (22) | 1.8 (0.8 to 4.0) | 0.18 |
| Physical examination | |||
| Temperature >38.5°C | 101 (72) | 3.6 (1.4 to 9.3) | 0.009 |
| Respiratory rate >18/minc | 34 (85) | 5.6 (0.6 to 53.4) | 0 |
| Biochemistryc | |||
| Sodium <130 mmol/L | 36 (26) | 2.1 (1.1 to 4.7) | 0.06 |
| Creatinine >100 µmol/L | 73 (52) | 2.1 (1.0 to 4.4) | 0.05 |
| CPK >200 U/L | 25 (50) | 1.4 (0.5 to 4.2) | 0.57 |
| ASAT >100 U/L | 21 (18) | 1.7 (0.6 to 4.4) | 0.30 |
| γ-GT >100 U/L | 12 (13) | 0.42 (0.09 to 2.03) | 0.28 |
| PO2 <9.7 kPa | 96 (83) | 0.64 (0.24 to 1.70) | 0.37 |
| X-ray results | |||
| Bilateral infiltratese | 38 (27) | 3.5 (1.6 to 7.6) | 0.002 |
| Pleural effusion | 15 (11) | 3.8 (1.2 to 11.3) | 0.002 |
| Progression within 48 hrsc,f | 46 (41) | 1.6 (0.7 to 3.4) | 0.25 |
aCI: confidence interval, COPD, chronic obstructive pulmonary disease, CPK, creatinine phosphokinase; ASAT, aspartate aminotransferase; γ-GT, gamma glutamyltransferase. bLogistic regression analysis. cData for smoking (≥1 cigarette per day), alcohol intake (≥2 U per day), breathing frequencies, laboratory tests, and progression of infiltrates were available for a proportion of patients. Cutoff levels for CPK, ASAT, and γ-GT are two times the upper normal limit. dImmunosuppressive medication is defined as ongoing treatment with chemotherapy or steroids >10 mg/day. eUnilateral infiltrate was the reference group. f Radiographic progression during 24–48 hours was defined as an increase in density or size of the infiltrate, or progression to multiple lobes.