Demographic and clinical data of the study population
Age group | p-value | ||
<65 yrs | ≥65 yrs | ||
Subjects n | 1298 | 1349 | |
Age yrs | 47.2±12.7 | 77.1±7.5 | |
Males/females n | 716/582 | 770/579 | 0.33 |
Body mass index kg·m−2 | 25.1±5.5 | 25.3±4.5 | 0.43 |
Smokers | 44.9 | 17.8 | <0.001 |
Body temperature °C | 37.9±1.2 | 37.7±1.1 | <0.001 |
Dyspnoea | 68.2 | 81.7 | <0.001 |
Purulent sputum | 53.3 | 62.3 | <0.001 |
Cough | 87.0 | 84.0 | 0.29 |
Pleuritic pain | 49.0 | 28.5 | <0.001 |
Pleuritic effusion | 12.6 | 18.3 | <0.001 |
Confusion | 5.2 | 16.4 | <0.001 |
BUN mM | 5.7±4.7 | 9.2±6.3 | <0.001 |
Respiratory frequency breaths·min−1 | 19.8±6.5 | 20.8±6.6 | <0.001 |
Blood pressure mmHg | |||
Systolic | 123.3±19.0 | 134.6±24.4 | <0.01 |
Diastolic | 74.7±11.8 | 75.9±13.6 | <0.001 |
Blood pH | 7.45±0.07 | 7.44±0.06 | <0.01 |
Pa,O2mmHg | 67.2±17.3 | 65.1±16.8 | <0.05 |
Pa,CO2mmHg | 35.4±8.2 | 36.9±8.7 | <0.05 |
Sa,O2 % | 92.6±6.1 | 91.4±5.7 | <0.01 |
Leukocytes cells·nL−1 | 12.6±6.2 | 13.3±6.1 | <0.01 |
C-reactive protein mg·L−1 | 137.4±127.9 | 139.6±118.6 | 0.68 |
Glucose mM | 6.6±2.9 | 8.1±3.8 | <0.001 |
Data are presented as mean±sd or %, unless otherwise indicated. BUN: blood urea nitrogen; Pa,O2: arterial oxygen tension; Pa,CO2: arterial carbon dioxide tension; Sa,O2: arterial oxygen saturation. 1 mmHg = 0.133 kPa.