TABLE 1.
Baseline characteristics.
| Total | Wuhan Strain | Beta | Delta | Omicron | p-value (Delta vs Omicron) | |
|---|---|---|---|---|---|---|
| n | 1689 | 571 | 611 | 374 | 133 | - |
| Patient characteristics | ||||||
| Sex, Male (%) | 761 (45.1) | 241 (42.2) | 281 (46.0) | 174 (46.5) | 65 (48.9) | 0.715 |
| Age, median (IQR] | 55.0 [44.2, 66.0] | 53.0 (41.0, 65.0] | 58.0 [47.5, 68.0] | 52.8 [43.9, 62.1] | 59.5 [47.5, 71.4] | < 0.001 |
| Symptoms | ||||||
| Cough (%) | 1271 (75.6) | 380 (66.5) | 458 (75.0) | 323 (87.5) | 110 (84.0) | 0.379 |
| Dyspnoea (%) | 1432 (85.1) | 421 (73.7) | 549 (89.9) | 346 (93.8) | 116 (88.5) | 0.081 |
| Fever (%) | 731 (43.5) | 264 (46.2) | 248 (40.6) | 163 (44.2) | 56 (42.7) | 0.857 |
| Anosmia (%) | 261 (15.5) | 65 (11.4) | 128 (20.9) | 59 (16.0) | 9 (6.9) | 0.014 |
| Myalgia (%) | 459 (27.3) | 143 (25.0) | 149 (24.4) | 126 (34.1) | 41 (31.3) | 0.627 |
| Comorbidities | ||||||
| Hypertension (%) | 873 (51.7) | 279 (48.9) | 335 (54.8) | 181 (48.4) | 78 (58.6) | 0.054 |
| Diabetes Mellitus (%) | 667 (39.5) | 199 (34.9) | 273 (44.7) | 143 (38.2) | 52 (39.1) | 0.943 |
| CKD (%) | 173 (10.2) | 43 (7.5) | 66 (10.8) | 35 (9.4) | 29 (21.8) | < 0.001 |
| HIV infection (%) | 169 (11.3) | 83 (14.5) | 34 (8.2) | 30 (8.0) | 27 (16.5) | 0.009 |
| Vaccination status | < 0.001 | |||||
| Unvaccinated | 1405 (83.2) | 571 (100.0) | 611 (100.0) | 149 (39.8) | 74 (55.6) | - |
| Vaccinated | 40 (2.4) | 0 (0.0) | 0 (0.0) | 17 (4.5) | 23 (17.3) | - |
| Status not recorded | 244 (14.4) | 0 (0.0) | 0 (0.0) | 208 (55.6) | 36 (27.1) | - |
| CRP (mg/L) [IQR] | 100 [47, 168] | 93 [43,182] | 100 [51, 149] | 109 [65, 183] | 90 [30, 196] | 0.224 |
| D-dimer (mg/L) [IQR] | 0.56 [0.34, 1.02] | 0.66 [0.35, 1.35] | 0.50 [0.33, 0.90] | 0.55 [0.34, 1.00] | 0.76 [0.47, 1.83] | 0.029 |
| PF ratio [IQR] | 169 [97, 259] | NA [NA, NA] | 200 [122, 281] | 111 [79, 202] | 172 [116, 244] | < 0.001 |
| Inpatient management and outcomes | ||||||
| Corticosteroids (%) | 1103 (65.4) | 78 (13.7) | 566 (92.6) | 352 (94.4) | 107 (81.7) | < 0.001 |
| Anticoagulation - enoxaparin (%) | 1403 (83.2) | 358 (62.7) | 571 (93.5) | 359 (96.2) | 115 (87.8) | 0.001 |
| Prophylactic enoxaparin dose | 570 (55.2) | NA (NA) | 218 (38.2) | 257 (73.6) | 95 (84.8) | 0.008 |
| Therapeutic enoxaparin dose | 462 (44.8) | NA (NA) | 353 (61.8) | 92 (26.4) | 17 (15.2) | - |
| High-flow nasal cannula (%) | 365 (21.6) | 49 (8.6) | 94 (15.4) | 202 (54.0) | 20 (15.3) | < 0.001 |
| ICU admission (%) | 120 (7.1) | 35 (6.1) | 36 (5.9) | 45 (12.1) | 4 (3.1) | 0.005 |
| Deceased (%) | 434 (25.7) | 127 (22.2) | 135 (22.1) | 138 (37.1) | 34 (25.8) | 0.024 |
Note: P-value denotes uni-variable comparisons between delta and omicron variants. CKD, Chronic kidney disease; CRP, C-reactive Protein; HIV, Human Immunodeficiency Virus; PaO2/FiO2 ratio, partial pressure of arterial oxygen/inspired oxygen fraction.