Distribution of demographic variables and clinical parameters in enrolled patients and comparison of survivors and non-survivors in the cohort
| Variables | Overall (n=451) N (%) | Survivor (n=386) N (%) | Non-survivor (n=65) N (%) | P value | |
| Age (mean±SD) | 51±12.4 | 50±12.4 | 56±11.3 | <0.001* | |
| Age | ≤40 | 104 (23.1) | 97 (25.1) | 7 (10.8) | 0.004 |
| 41–59 | 225 (49.9) | 194 (50.3) | 31 (47.7) | ||
| ≥60 | 122 (27.1) | 95 (24.6) | 27 (41.5) | ||
| Gender: male | 346 (76.7) | 294 (76.2) | 52 (80.0) | 0.499 | |
| Blood group | A | 104 (23.1) | 91 (23.6) | 13 (20.0) | 0.518 |
| B | 164 (36.4) | 140 (36.3) | 24 (36.9) | ||
| AB | 25 (5.5) | 19 (4.9) | 6 (9.2) | ||
| O | 158 (35.0) | 136 (35.2) | 22 (33.8) | ||
| History of smoking | 37 (8.2) | 32 (8.3) | 5 (7.7) | 0.866 | |
| Comorbidities and chronic illness | |||||
| Diabetes | 196 (43.5) | 164 (42.5) | 32 (49.2) | 0.310 | |
| Hypertension | 169 (37.5) | 139 (36.0) | 30 (46.2) | 0.118 | |
| Chronic obstructive pulmonary disease | 15 (3.3) | 10 (2.6) | 5 (7.7) | 0.050 | |
| Obesity ≥30 | 31 (6.9) | 25 (6.5) | 6 (9.2) | 0.426 | |
| Chronic kidney disease | 17 (3.8) | 11 (2.8) | 6 (9.2) | 0.024 | |
| Coronary artery disease | 31 (6.9) | 23 (6.0) | 8 (12.3) | 0.106 | |
| Cerebrovascular disease | 4 (0.9) | 3 (0.8) | 1 (1.5) | 0.465 | |
| Symptoms at admission | |||||
| Shortness of breath | 413 (91.6) | 351 (90.9) | 62 (95.4) | 0.232 | |
| Fever | 158 (35.0) | 128 (33.2) | 30 (46.2) | 0.042 | |
| Cough | 309 (68.5) | 259 (67.1) | 50 (76.9) | 0.115 | |
| Fatigue | 354 (78.7) | 301 (78.2) | 53 (81.5) | 0.541 | |
| Severity of illness score | |||||
| SOFA score at admission* | 2.40±1.06 | 2.30±0.93 | 3.05±1.49 | <0.001 | |
| Treatment | |||||
| Vasopressor | 18 (4.0) | 1 (0.3) | 17 (26.6) | <0.001 | |
| Non-invasive ventilation (NIV) | 446 (98.9) | 383 (99.2) | 63 (96.9) | 0.101 | |
| Invasive ventilation | 38 (8.4) | 4 (1.04) | 34 (52.31) | <0.001 | |
| Interval between symptom onset and admission† | 4 (3, 7) | 4 (3, 7) | 4 (3, 6) | 0.996 | |
| Duration of respiratory support, days† | 6 (4, 10) | 6 (4, 9.5) | 6 (3, 10) | 0.689 | |
| Duration of invasive ventilation, days† | 1 (1,3) | 12 (2, 14) | 1 (1, 3) | 0.020 | |
| Duration of hospital stay, days† | 14 (10, 18) | 14 (11, 19) | 8 (5, 14) | <0.001 | |
P values are highlighted in bold for statistically significant factors.
*Mean±SD—independent t-test was used.
†Median (IQR) days in days—Mann-Whitney U test was used.
SOFA, Sequential Organ Failure Assessment.