Table 1.
Patients’ Characteristics, n=298.
| Characteristics | Value | Characteristics | Value | |||
|---|---|---|---|---|---|---|
| Male sex | 205 (68.8) | Laboratory data | ||||
| Age, years | 61.1±14.6 | Arterial blood gas analysis | ||||
| <65 | 168 (56.4) | PaCO2, Torr | ||||
| 65-74 | 79 (26.5) | Unknown | 8 (2.7) | |||
| 75≤ | 51 (17.1) | <35 | 160 (53.7) | |||
| Body mass index (BMI), kg/m2 | 25.5±4.54 | 35-45 | 124 (41.6) | |||
| 30≤ BMI | 44 (14.8) | 45≤ | 6 (2.0) | |||
| BMI <18 | 7 (2.3) | Lactate, mmol/L | ||||
| BMI 18≤, <30 | 233 (78.1) | Unknown | 36 (12.1) | |||
| BMI, unknown | 14 (4.7) | <2 | 221 (74.2) | |||
| Days from onset to admission | 7 (0-19) | 2≤ | 41 (13.8) | |||
| Antibiotics prior to admission, yes | 39 (13.1) | WBC, /mm3 | 6,484±3,049 | |||
| Smoking history, yes | 145 (48.7) | Plt, /mm3 | 20.9±7.7 | |||
| Underlying diseases, none | 109 (36.6) | Neutrophils, /mm3 | 4,971±2,993 | |||
| Pulmonary diseases | Lymphocytes, /mm3 | 1,073±508 | ||||
| COPD | 17 (5.7) | Unknown | 0 | |||
| Bronchial asthma | 14 (4.7) | <500 | 21 (7.0) | |||
| Bronchiectasis | 1 (0.3) | 500≤ | 277 (93.0) | |||
| Pulmonary nontuberculous mycobacteriosis | 1 (0.3) | D-dimer, μg/mL | 1.74±3.36 | |||
| Old tuberculosis | 2 (0.7) | Unknown | 3 (1.0) | |||
| Interstitial lung diseases | 8 (2.7) | <2 | 255 (85.6) | |||
| Post lung cancer operation | 4 (1.3) | 2≤ | 40 (13.4) | |||
| Pneumoconiosis | 1 (0.3) | AST, IU/L | 41±38 | |||
| Chronic pulmonary artery thromboembolism | 1 (0.3) | ALT, IU/L | 35±33 | |||
| Non-pulmonary diseases | LDH, IU/L | 281±116 | ||||
| None | 120 (40.2) | CK, IU/L | 150±424 | |||
| Hypertension | 100 (33.6) | BUN, mg/dL | 16±9 | |||
| Congestive heart failure | 3 (1.0) | BUN ≥20 | ||||
| Ischemic heart diseases | 19 (6.4) | Cre, mg/dL | 0.88±0.34 | |||
| Diabetes mellitus | 92 (30.9) | Na, mmol/L | 137±8 | |||
| Valvular diseases | 1 (0.3) | CRP, mg/dL | 5.6±5.8 | |||
| Arrythmias | 9 (3.0) | KL-6, U/mL | 337±321 | |||
| Cardiomyopathy | 2 (0.7) | Unknown | 8 (2.7) | |||
| Cerebrovascular diseases | 7 (2.3) | <500 | 251 (84.2) | |||
| Dementia | 4 (1.3) | 500≤ | 39 (13.1) | |||
| Neuromuscular diseases | 4 (1.3) | Ferritin, ng/mL | 743±703 | |||
| Post upper digestive system surgery | 4 (1.3) | Unknown | 8 (2.7) | |||
| Chronic liver diseases | 5 (1.7) | <500 | 144 (48.3) | |||
| Connective tissue diseases | 3 (1.0) | 500-1,000 | 76 (25.5) | |||
| Systemic steroids or immunosuppressants | 7 (2.3) | 1,000≤ | 70 (23.5) | |||
| Psychiatric diseases | 2 (0.7) | Procalcitonin, ng/mL | 0.235±1.625 | |||
| Malignancy | 9 (3.0) | Unknown | 11 (3.7) | |||
| Heavy drinker | 1 (0.3) | <0.5 | 275 (92.3) | |||
| Chronic kidney disease | 6 (20.1) | 0.5≤, <1 | 8 (2.7) | |||
| Long-term oxygen therapy | 1 (0.3) | 1≤ | 4 (1.3) | |||
| Vaccination history, pneumococcus | 25 (8.4) | Complications | ||||
| Vaccination history, influenza virus | 73 (24.5) | Deep vein thrombosis | 4 (1.3) | |||
| Premorbid performance status | Acute pulmonary thromboembolism | 1 (0.3) | ||||
| 0 | 262 (87.9) | Pneumothorax | 1 (0.3) | |||
| 1-2 | 29 (9.7) | Pulmonary hemorrhage | 1 (0.3) | |||
| 3-4 | 6 (2.0) | Acute kidney injury | 16 (5.4) | |||
| Viral coinfection, yes | 91 (30.5) | qSOFA, 2≤ | 2 (0.7) | |||
| Bacterial coinfection, yes | 29 (9.7) | Severity, severe | 46 (15.4) | |||
| Treatment during hospital stay | ||||||
| Antibiotics, yes | 114 (38.3) | |||||
| Neuraminidase inhibitors, yes | 112 (37.6) | |||||
| Corticosteroids, yes | 100 (33.6) | |||||
| Day from onset to start corticosteroid | 8 (0-18) | |||||
| HFNC | 46 (15.4) | |||||
| IMV | 30 (10.1) | |||||
| Continuous renal replacement therapy | 1 (0.3) | |||||
| ECMO | 6 (2.0) | |||||
| Days from onset to HFNC | 9 (3-15) | |||||
| Days from onset to IMV | 11 (4-19) | |||||
| Days from admission to IMV | 2.5 (-1-18) | |||||
| Follow-up period, from onset | 42 (6-398) | |||||
| Mortality | 23 (7.7) |
qSOFA: quick Sequential Organ Failure Assessment Score, IMV: invasive mandatory ventilation, HFNC: high-flow nasal canula, ECMO: extracorporeal membrane oxygenation