Characteristics of patients with COVID-19 stratified by analysis group and survival status*
| Combined | Training set | Testing set | |||||||
| All individuals (n=15 502) | Survived (n=14 608) | Died (n=894) | All (n=11 635) | Survived (n=10 926) | Died (n=709) | All (n=3867) | Survived (n=3682) | Died (n=185) | |
| Age in years—mean±SD | 56.01±17.98 | 54.73±17.43 | 76.95±13.22 | 56.10±17.96 | 54.75±17.37 | 76.89±13.39 | 55.73±18.04 | 54.66±17.59 | 77.17±12.55 |
| Age categories | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| 20–29 years | 1499 (9.7) | 1495 (10.2) | 4 (0.4) | 1125 (9.7) | 1121 (10.3) | 4 (0.6) | 374 (9.7) | 374 (10.2) | 0 (0) |
| 30–49 years | 4145 (26.7) | 4115 (28.2) | 30 (3.4) | 3048 (26.2) | 3024 (27.7) | 24 (3.4) | 1097 (28.4) | 1091 (29.6) | 6 (3.2) |
| 50–64 years | 4866 (31.4) | 4746 (32.5) | 120 (13.4) | 3721 (32.0) | 3626 (33.2) | 95 (13.4) | 1145 (29.6) | 1120 (30.4) | 25 (13.5) |
| 65–79 years | 3479 (22.4) | 3143 (21.5) | 336 (37.6) | 2608 (22.4) | 2340 (21.4) | 268 (37.8) | 871 (22.5) | 803 (21.8) | 68 (36.8) |
| ≥80 years | 1513 (9.8) | 1109 (7.6) | 404 (45.2) | 1133 (9.7) | 815 (7.5) | 318 (44.9) | 380 (9.8) | 294 (8.0) | 86 (46.5) |
| Sex—no (%) | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Female | 9118 (58.8) | 8713 (59.6) | 405 (45.3) | 6835 (58.7) | 6510 (59.6) | 325 (45.8) | 2283 (59.0) | 2203 (59.8) | 80 (43.2) |
| Male | 6384 (41.2) | 5895 (40.4) | 489 (54.7) | 4800 (41.3) | 4416 (40.4) | 384 (54.2) | 1584 (41.0) | 1479 (40.2) | 105 (56.8) |
| Race-ethnicity—no (%) | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| African American | 4117 (26.6) | 3856 (26.4) | 261 (29.2) | 3109 (26.7) | 2894 (26.5) | 215 (30.3) | 1008 (26.1) | 962 (26.1) | 46 (24.9) |
| European American | 9176 (59.2) | 8623 (59.0) | 553 (61.9) | 6828 (58.7) | 6400 (58.6) | 428 (60.4) | 2348 (60.7) | 2223 (60.4) | 125 (67.6) |
| Asian | 284 (1.8) | 280 (1.9) | 4 (0.4) | 220 (1.9) | 217 (2.0) | 3 (0.4) | 64 (1.7) | 63 (1.7) | 1 (0.5) |
| Latino | 609 (3.9) | 586 (4.0) | 23 (2.6) | 473 (4.1) | 452 (4.1) | 21 (3.0) | 136 (3.5) | 134 (3.6) | 2 (1.1) |
| Other or unknown† | 1316 (8.5) | 1263 (8.6) | 53 (5.9) | 1005 (8.6) | 963 (8.8) | 42 (5.9) | 311 (8.0) | 300 (8.1) | 11 (5.9) |
| BMI in kg/meter2—mean±SD‡ | 31.83±7.88 | 31.98±7.83 | 29.45±8.38 | 31.82±7.89 | 31.97±7.82 | 29.54±8.59 | 31.86±7.87 | 32.00±7.86 | 29.10±7.53 |
| BMI categories | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| <18.5 (underweight) | 143 (0.9) | 108 (0.7) | 35 (3.9) | 114 (1.0) | 85 (0.8) | 29 (4.1) | 29 (0.7) | 23 (0.6) | 6 (3.2) |
| 18.5 to <25 (normal weight) | 2714 (17.5) | 2461 (16.8) | 253 (28.3) | 2019 (17.4) | 1821 (16.7) | 198 (27.9) | 695 (18.0) | 640 (17.4) | 55 (29.7) |
| 25 to <30 (overweight) | 4378 (28.2) | 4123 (28.2) | 255 (28.5) | 3302 (28.4) | 3095 (28.3) | 207 (29.2) | 1076 (27.8) | 1028 (27.9) | 48 (25.9) |
| 30 to <35 (class-1 obesity) | 3788 (24.4) | 3611 (24.7) | 177 (19.8) | 2852 (24.5) | 2714 (24.8) | 138 (19.5) | 936 (24.2) | 897 (24.4) | 39 (21.1) |
| 35 to <40 (class-2 obesity) | 2270 (14.6) | 2189 (15.0) | 81 (9.1) | 1684 (14.3) | 1625 (14.9) | 59 (8.3) | 586 (15.2) | 564 (15.3) | 22 (11.9) |
| ≥40 (class-3 obesity) | 2209 (14.2) | 2116 (14.5) | 93 (10.4) | 1664 (14.3) | 1586 (14.5) | 78 (11.0) | 545 (14.1) | 530 (14.4) | 15 (8.1) |
| Serum creatinine in mg/dL – (mean±SD)‡ | 1.02±1.03 | 0.99±0.96 | 1.58±1.76 | 1.03±1.05 | 0.99±0.96 | 1.62±1.85 | 1.01±0.98 | 0.99±0.95 | 1.46±1.34 |
| Smoking status – no (%) | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Ever smoker§ | 6505 (42.0) | 5962 (40.8) | 543 (60.7) | 4874 (41.9) | 4444 (40.7) | 430 (60.6) | 1631 (42.2) | 1518 (41.2) | 113 (61.1) |
| Never smoker | 8997 (58.0) | 8646 (59.2) | 351 (39.3) | 6761 (58.1) | 6482 (59.3) | 279 (39.4) | 2236 (57.8) | 2164 (58.8) | 72 (38.9) |
| Occupation | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Healthcare worker | 307 (2.0) | 304 (2.1) | 3 (0.3) | 229 (2.0) | 227 (2.1) | 2 (0.3) | 78 (2.0) | 77 (2.1) | 1 (0.5) |
| Other | 2086 (13.5) | 1975 (13.5) | 111 (12.4) | 1583 (13.6) | 1492 (13.7) | 91 (12.8) | 503 (13.0) | 483 (13.1) | 20 (10.8) |
| Unknown | 13 109 (84.6) | 12 329 (84.4) | 780 (87.2) | 9823 (84.4) | 9207 (84.3) | 616 (86.9) | 3286 (85.0) | 3122 (84.8) | 164 (88.6) |
*The training set comprised individuals used to identify risk factors for COVID-19-related death; these individuals were used to create the prediction model. The testing set comprised a separate group of individuals used to test the performance of the prediction model.
†Other or unknown race-ethnicity included individuals who did not identify as exclusively African American, European American, Asian or Latino. This group also included individuals who identified as being part of multiple groups.
‡This was based on the most recent measure of BMI or creatinine >1 month prior to the index date. Index date was defined as the date that the first SARS-CoV-2 test was collected.
§Ever smokers included both past and current smokers.
BMI, body mass index.