Table 1 Characteristics of the study population by origin
|  | Overall n = 1179 | Non-Italians n = 258 | Italians n = 921 | p-value |
|---|---|---|---|---|
Median age [IQR] | 65 [53, 76] | 51 [41, 60] | 70 [58, 79] |  < 0.001 |
Age ≥ 65 years, n (%) | 585 (49.6) | 40 (15.5) | 545 (59.2) |  < 0.001 |
Biological sex | Â | Â | Â | Â |
 Female, n (%) | 400 (33.9) | 86 (33.3) | 314 (34.1) | 0.882 |
 Male, n (%) | 779 (66.1) | 172 (66.7) | 607 (65.9) |  |
Co-morbidities | Â | Â | Â | Â |
 Obesitya, n (%) | 231 (19.6) | 60 (23.3) | 171 (18.6) | 0.110 |
 Diabetes, n (%) | 166 (14.1) | 32 (12.4) | 134 (14.5) | 0.419 |
 Lung diseases, n (%) | 199 (16.9) | 29 (11.2) | 170 (18.5) | 0.006 |
 Heart diseases, n (%) | 634 (53.8) | 76 (29.5) | 558 (60.6) |  < 0.001 |
 Renal diseases, n (%) | 116 (9.8) | 22 (8.5) | 94 (10.2) | 0.479 |
 Oncological diseases, n (%) | 151 (12.8) | 17 (6.6) | 134 (14.5) |  < 0.001 |
 Immune system diseases, n (%) | 90 (7.6) | 19 (7.4) | 71 (7.7) | 0.999 |
 Liver diseases, n (%) | 38 (3.2) | 13 (5.0) | 25 (2.7) | 0.072 |
Number of co-morbidities | Â | Â | Â | Â |
 0 | 311 (26.4) | 119 (46.1) | 192 (20.8) |  < 0.001 |
 1 | 377 (32.0) | 68 (26.4) | 309 (33.6) |  |
 2 | 304 (25.8) | 41 (15.9) | 263 (28.6) |  |
 3 +  | 187 (15.9) | 30 (11.6) | 157 (17.0) |  |
Median number of days from symptom onset [IQR] | 7 [3, 10] | 6.00 [3, 9] | 7 [3, 10] | 0.026 |
Disease severity upon hospital admissionb | Â | Â | Â | Â |
 Mild | 113 (9.6) | 31 (12.0) | 82 (8.9) | 0.242 |
 Moderate | 487 (41.3) | 113 (43.8) | 374 (40.6) |  |
 Severe | 279 (23.7) | 54 (20.9) | 225 (24.4) |  |
 Critical | 300 (25.4) | 60 (23.3) | 240 (26.1) |  |