Table 2.
The clinical profile, laboratory, electrocardiogram findings and clinical outcomes of COVID-19 patients according to symptom and admission fever profile (N=554)
| Group 1: asymptomatic and afebrile (N=41) | Group 2: symptomatic but afebrile (N=311) | Group 3: febrile but asymptomatic (N=35) | Group 4: symptomatic and febrile (N=167) | P-value | |
|---|---|---|---|---|---|
| Clinical profile | |||||
| Day of illness at presentation | N.A. | 3 (4) | 2 (5) | 4 (6) | 0.150 |
| Length of days with fever | 0 | 0 | 1.6 (1.1) | 2.6 (2.5) | <0.001 |
| Admission temperature (°C) | 37.0 (0.6) | 37.1 (0.5) | 38.3 (0.5) | 38.3 (0.7) | <0.001 |
| Admission systolic blood pressure (mmHg) | 129 (22) | 129 (18) | 133 (16) | 133 (16) | 0.104 |
| Admission diastolic blood pressure (mmHg) | 82 (12) | 80 (13) | 84 (9) | 81 (12) | 0.425 |
| Admission oxygen saturation (%) | 98 (1) | 98 (2) | 98 (1) | 97 (3) | 0.021 |
| Admission pulse rate (beats per min) | 91 (17) | 89 (13) | 102 (17) | 103 (20) | <0.001 |
| Discharge systolic blood pressure (mmHg) | 114 (11) | 116 (13) | 117 (13) | 117 (14) | 0.462 |
| Discharge diastolic blood pressure (mmHg) | 71 (10) | 70 (11) | 74 (10) | 73 (10) | 0.090 |
| Discharge pulse rate (beats per min) | 74 (15) | 76 (12) | 75 (12) | 75 (11) | 0.957 |
| Laboratory investigations | |||||
| Leucocyte (×109/l) | 6.6 (1.9) | 6.4 (2.0) | 6.2 (1.6) | 6.5 (2.7) | 0.864 |
| Neutrophil (×109/l) | 3.8 (2.7) | 3.7 (2.0) | 4.0 (1.4) | 4.2 (2.5) | 0.101 |
| Eosinophil (×109/l) | 0.7 (1.8) | 0.6 (1.6) | 0.5 (1.6) | 0.6 (1.9) | 0.962 |
| Lymphocyte (×109/l) | 2.2 (1.1) | 2.1 (1.6) | 1.3 (0.5) | 1.7 (2.9) | 0.033 |
| Monocyte (×109/l) | 0.9 (1.4) | 0.7 (0.5) | 1.0 (0.3) | 1.0 (2.1) | 0.071 |
| Haemoglobin (g/dl) | 15.3 (1.6) | 14.8 (1.7) | 15.2 (1.0) | 14.7 (1.7) | 0.111 |
| Platelet (×109/l) | 225 (54) | 237 (63) | 222 (47) | 213 (55) | 0.001 |
| Neutrophil–lymphocyte ratio | 2.10 (1.83) | 2.26 (2.29) | 7.00 (22.17) | 3.81 (3.68) | <0.001 |
| Platelet–lymphocyte ratio | 119.5 (69.6) | 136.2 (60.1) | 386.3 (1216.0) | 177.7 (88.7) | <0.001 |
| Haematocrit (%) | 45 (3) | 46 (29) | 45 (3) | 45 (15) | 0.962 |
| Sodium (mmol/l) | 138 (2) | 138 (3) | 138 (2) | 137 (3) | 0.001 |
| Creatinine (mmol/l) | 76 (11) | 77 (36) | 82 (15) | 84 (23) | 0.108 |
| Estimated glomerular filtration rate (ml/min) | 112 (13) | 109 (18) | 103 (15) | 97 (19) | <0.001 |
| Albumin (g/l) | 32 (2) | 44 (22) | 43 (3) | 42 (17) | 0.830 |
| Total bilirubin (umol/l) | 14 (8) | 12 (9) | 11 (7) | 11 (5) | 0.160 |
| Aspartate aminotransferase (U/l) | 35 (14) | 36 (60) | 35 (15) | 42 (32) | 0.713 |
| Alanine aminotransferase (U/l) | 43 (27) | 45 (48) | 47 (37) | 47 (43) | 0.953 |
| Lactate dehydrogenase (ng/l) | 398 (123) | 410 (338) | 383 (73) | 506 (613) | 0.102 |
| D-dimer (ug/ml) | 0.3 (0.3) | 0.7 (0.4) | 0.5 (0.2) | 2.3 (6.0) | 0.873 |
| C-reactive protein (mg/l) | 7 (5) | 10 (24) | 10 (6) | 23 (34) | <0.001 |
| Ferritin | 165 (169) | 156 (162) | 137 (72) | 234 (309) | 0.003 |
| Electrocardiogram | |||||
| Ventricular rate (beats per min) | 75 (13) | 74 (13) | 84 (14) | 85 (18) | <0.001 |
| PR interval (ms) | 151 (31) | 161 (123) | 144 (18) | 149 (23) | 0.481 |
| QRS duration (ms) | 88 (9) | 89 (12) | 89 (12) | 89 (13) | 0.951 |
| Corrected QT interval (ms) | 412 (20) | 419 (25) | 418 (21) | 422 (26) | 0.168 |
| Presence of ST-segment depression | 0 | 0 | 0 | 4 (2.6) | 0.025 |
| Rhythm | <0.001 | ||||
| Sinus rhythm | 27 (67.5) | 224 (77.5) | 28 (82.4) | 112 (70.9) | |
| Sinus tachycardia | 4 (10.0) | 11 (3.8) | 3 (8.8) | 34 (21.5) | |
| Sinus bradycardia | 9 (22.5) | 53 (18.3) | 3 (8.8) | 12 (7.6) | |
| Atrial fibrillation | 0 | 1 (0.3) | 0 | 0 | |
| Clinical outcomes | |||||
| Pneumonia | 1 (2.4) | 19 (6.1) | 3 (8.6) | 34 (20.4) | <0.001 |
| Pleural effusion | 0.532 | ||||
| Unilateral | 0 | 0 | 0 | 2 (1.3) | |
| Bilateral | 0 | 1 (0.4) | 0 | 1 (0.6) | |
| Acute respiratory distress syndrome | 0 | 4 (1.3) | 0 | 8 (4.8) | 0.041 |
| Acute kidney injury | 1 (2.4) | 12 (3.9) | 3 (8.6) | 29 (17.4) | <0.001 |
| Requiring dialysis | 0 | 3 (1.0) | 0 | 4 (2.4) | 0.406 |
| Pulmonary embolism | 0 | 1 (0.4) | 0 | 5 (4.2) | 0.035 |
| Coagulopathy | 0 | 0 | 0 | 3 (1.8) | 0.011 |
| Acute myocardial infarction | 0 | 1 (0.3) | 0 | 0 | 0.198 |
| Ventricular tachycardia | 0 | 0 | 0 | 1 (0.8) | 0.487 |
| Myocarditis/myocardial injury | 0 | 2 (0.9) | 0 | 1 (0.8) | 0.899 |
| Heart failure | 0 | 1 (0.5) | 0 | 0 | 0.842 |
| Stroke | 0 | 0 | 0 | 1 (0.8) | 0.483 |
| Supplementary oxygen on general ward | 0 | 3 (1.0) | 0 | 12 (7.2) | <0.001 |
| Persistent fever >72 h | 0 | 3 (1.0) | 3 (8.6) | 34 (20.5) | <0.001 |
| Intensive care unit admission | 0 | 6 (1.9) | 0 | 13 (7.8) | 0.003 |
| Mechanical ventilation | 0 | 6 (1.9) | 0 | 10 (6.0) | 0.029 |
| Inotropes | 0 | 3 (1.3) | 0 | 5 (4.0) | 0.203 |
| All-cause mortality | 0 | 0 | 0 | 2 (1.7) | 0.185 |
| Composite study end-point | 1 (2.4) | 15 (4.8) | 3 (8.6) | 40 (24.0) | <0.001 |