Table 1.
Baseline characteristics of study patients
| Characteristics | Disease severity | |||
|---|---|---|---|---|
| Asymptomatic/mild (n = 63, 13.0%) | Moderate (n = 378, 78.1%) | Sever/critically ill (n = 43, 8.9%) | p value | |
| Age (years) | 33 (22, 51) | 46 (34, 56) | 59 (52, 71) | < 0.001 |
| Gender, male | 31/63 (49.2%) | 202/378 (53.4%) | 27/43 (62.8%) | 0.377 |
| Incubation period (days) | 8 (5, 11) | 6 (3, 10) | 5 (3, 8) | 0.125 |
| Initial symptoms | ||||
| Fever | 14/30 (46.7%)c | 278/378 (73.5%) | 36/43 (83.7%) | < 0.001 |
| Cough/sputum | 19/30 (63.3%)c | 224/378 (59.3%) | 30/43 (69.8%) | < 0.001 |
| Shortness of breath/dyspnea | 0/30 (0%)c | 10/378 (2.7%) | 5/43 (11.6%) | 0.007 |
| Comorbiditya | 8/63 (12.7%) | 76/378 (20.1%) | 16/43 (37.2%) | 0.008 |
| Exposure type | ||||
| Wuhan exposure | 18/63 (28.6%) | 148/378 (39.2%) | 16/43 (37.2%) | 0.275 |
| COVID-19 patients exposure | 34/63 (54.0%) | 139/378 (36.8%) | 12/43 (27.9%) | 0.012 |
| Contact historyb | 8/63 (12.7%) | 40/378 (10.6%) | 8/43 (18.6%) | 0.284 |
| No exposure | 3/63 (4.8%) | 51/378 (13.5%) | 7/43 (16.3%) | 0.116 |
| Type of disease | ||||
| Single onset | 10/63 (15.9%) | 199/378 (52.6%) | 23/43 (53.5%) | < 0.001 |
| Clustering onset | 53/63 (84.1%) | 179/378 (47.4%) | 20/43 (46.5%) | < 0.001 |
| Laboratory tests | ||||
| SaO2 (%) | 98.2 (98.0, 98.4) | 97.9 (96.4, 99.0) | 95.3 (93.2, 97.3) | < 0.001 |
| Blood leukocyte count (× 10^9/L) | 5.3 (4.5, 6.6) | 4.8 (3.8, 6.0) | 4.2 (3.5, 5.9) | 0.033 |
| < 4 × 10^9/L | 9/57 (15.8%) | 93/309 (30.1%) | 14/37 (37.8%) | 0.040 |
| > 10 × 10^9/L | 1/57 (1.8%) | 5/309 (1.6%) | 3/37 (8.1%) | 0.077 |
| Lymphocyte count (× 10^9/L) | 1.8 (1.3, 2.5) | 1.3 (1.0, 1.7) | 0.6 (0.5, 0.9) | < 0.001 |
| < 1.5 × 10^9/L | 18/54 (33.3%) | 195/318 (61.3%) | 36/37 (97.3%) | < 0.001 |
| Platelet count (× 10^9/L) | 216 (164, 263) | 182 (152, 212) | 154 (120, 191) | < 0.001 |
| < 150 × 10^9/L | 9/58 (15.5%) | 71/322 (22.0%) | 15/37 (40.5%) | 0.014 |
| C-reactive protein (≥ 10 mg/L) | 4/50 (8.0%) | 143/300 (47.7%) | 19/31 (61.3%) | < 0.001 |
| Procalcitonin (≥ 0.5 ng/mL) | 5/50 (10.0%) | 55/295 (18.6%) | 6/27 (22.2%) | 0.274 |
| Lactate dehydrogenase (≥ 250 U/L) | 6/37 (16.2%) | 103/232 (44.4%) | 17/26 (65.4%) | < 0.001 |
| Aspartate aminotransferase (> 40 U/L) | 4/48 (8.3%) | 71/270 (26.3%) | 13/30 (43.3%) | 0.002 |
| Alanine aminotransferase (> 40 U/L) | 6/46 (13%) | 70/273 (25.6%) | 8/30 (26.7%) | 0.170 |
| D-dimer (≥ 0.5 mg/L) | 11/54 (20.4%) | 75/311 (24.1%) | 17/36 (47.2%) | 0.007 |
| Creatine (μmol/L) | 63 (47, 79) | 63 (50, 78) | 62 (51, 82) | 0.975 |
| ICU /IMV/CRRT/ECMO | 1/63 (1.6%) | 13/378 (3.4%) | 15/43 (34.9%) | < 0.001 |
Categorical variables are expressed as number (percentage) while continuous variables are described as median and interquartile range
ICU intensive care unit, IMV invasive mechanical ventilation, CRRT continuous renal replacement therapy, ECMO extracorporeal membrane oxygenation
aComorbidity include hypertension, coronary heart disease, cardiac dysfunction III–IV, poor physical fitness (unable to climb stairs, do daily housework, etc.), gastrointestinal hemorrhage caused by cirrhosis, hepatic encephalopathy and portal hypertension, diabetes, chronic kidney dysfunction, dialysis, malignant tumor, hematological malignancies, connective tissue disease, and stroke
bContact history refers to those patients who had contact with people from Wuhan before the onset of disease
cA total of 33 patients were asymptomatic in the asymptomatic/mild group and were excluded when calculating the symptom percentage