Table 1.
Demographic and clinical characteristics among patients included in the development and validation cohorts
| Development cohort |
Validation cohort |
||||
|---|---|---|---|---|---|
| No of patients (%) or mean ± SD | Total No (%) | No of patients (%) or mean ± SD | Total No (%) | ||
| Characteristics of the population | |||||
| Critical illness | 1967 (25.1%) | 7850 (100%) | 698 (27.0%) | 2583 (100%) | |
| Age [years] | 65.8 ± 16.4 | 7816 (99.6%) | 69.5 ± 16.0 | 2575 (97.3%) | |
| Male | 4483 (57.2%) | 7834 (99.8%) | 1415 (54.8%) | 2580 (99.9%) | |
| Ethnicity | Caucasian | 6836 (89.1%) | 7677 (98.8%) | 2340 (91.0%) | 2572 (99.6%) |
| Latino | 693 (9.0%) | 193 (7.5%) | |||
| Other | 148 (1.9%) | 39 (1.5%) | |||
| Smoking history | Never | 5270 (70.9%) | 7433 (94.7%) | 1625 (65.7%) | 2475 (95.8%) |
| Former smoker | 1764 (23.7%) | 718 (29.0%) | |||
| Active Smoker | 399 (5.4%) | 139 (5.3%) | |||
| Medical history | |||||
| Obesitya | 1665 (23.7%) | 7012 (89.3%) | 584 (24.3%) | 2401 (93.0%) | |
| Hypertension | 3803 (48.6%) | 7833 (99.8%) | 1444 (56.1%) | 2576 (99.7%) | |
| Diabetes mellitus | 1440 (18.4%) | 7820 (99.6%) | 509 (19.8%) | 2570 (99.5%) | |
| Cardiovascular diseaseb | 1974 (25.3%) | 7800 (99.4%) | 806 (31.7%) | 2545 (98.5%) | |
| Pulmonary diseasesc | 1625 (20.9%) | 7776 (99.1%) | 576 (22.6%) | 2583 (98.9%) | |
| Severe chronic kidney diseased | 488 (6.2%) | 7825 (99.7%) | 163 (6.3%) | 2583 (99.7%) | |
| Malignancye | 793 (10.2%) | 7803 (99.4%) | 259 (10.1%) | 2571 (99.5%) | |
| Immunocompromised statusf | 650 (8.6%) | 7549 (96.2%) | 187 (7.6%) | 2473 (95.7%) | |
| Dependency (moderate/severe)g | 1129 (14.7%) | 7701 (98.1%) | 605 (23.7%) | 2555 (98.9%) | |
| Symptoms at admission | |||||
| Feverh | 5138 (67.0%) | 7663 (97.6%) | 1670 (65.6%) | 2544 (98.5%) | |
| Dyspnoea | 4427 (56.7%) | 7805 (99.4%) | 1523 (59.4%) | 2562 (99.2%) | |
| Clinical signs and physical exploration at admission | |||||
| SBP (mmHg) | 129.0 ± 21.5 | 7430 (94.6%) | 127.6 ± 21.0 | 2451 (94.9%) | |
| HR (beats/minute) | 88.6 ± 17.4 | 7500 (95.5%) | 87.5 ± 17.5 | 2504 (96.9%) | |
| Tachypnoea (>20 breaths/min) | 2271 (29.9%) | 7604 (96.9%) | 879 (35.1%) | 2504 (96.9%) | |
| SpO2 ≤93% or oxygen requirement at presentation | 4152 (52.9%) | 7842 (99.9%) | 1605 (62.1%) | 2583 (100%) | |
| Pulmonary rales | 4630 (60.7%) | 7626 (97.1%) | 1588 (63.6%) | 2495 (96.6%) | |
| Confusion | 849 (11.0%) | 7736 (98.5%) | 384 (15.1%) | 2546 (98.6%) | |
SD, standard deviation; HR, heart rate; SBP, systolic blood pressure; SpO2, peripheral oxygen saturation.
Obesity is defined as medical history or body mass index ≥30 kg/m2.
History of cerebrovascular disease, peripheral arterial disease, myocardial infarction, angina pectoris, heart failure or atrial fibrillation.
Chronic obstructive pulmonary disease, obstructive sleep apnoea/hypopnoea syndrome and asthma.
History of serum creatinine level >3 mg/dL or history of dialysis.
History of solid tumour, leukaemia or lymphoma.
History of autoimmune diseases, solid-organ transplant recipients, HIV infection or previous immunosuppressive treatment including systemic steroids.
Moderate or severe dependency for activities of daily living (Barthel index score <60).
Temperature ≥38°C or history of fever.