Baseline characteristics of adults in Alberta and Ontario admitted to hospital with a positive test for SARS-CoV-2 and who were discharged alive after a hospital stay of 30 days or less, between Jan. 1, 2020, and Sept. 30, 2021, stratified by readmission or death within 30 days of discharge
| Characteristic | No. (%) of patients in Alberta* | No. (%) of patients in Ontario* | ||||
|---|---|---|---|---|---|---|
| Overall n = 7875 | Readmission or death within 30 days n = 783 | No readmission or death within 30 days n = 7092 | Overall n = 22 461 | Readmission or death within 30 days n = 2390 | No readmission or death within 30 days n = 20 071 | |
| Age at time of admission, yr, mean ± SD | 57.44 ± 17.28 | 66.06 ± 18.29 | 56.90 ± 17.06 | 61.4 ± 17.2 | 70.1 ± 17.1 | 60.4 ± 16.9 |
| Sex, male | 4429 (56.2) | 464 (59.3) | 3965 (55.9) | 12 333 (54.9) | 1314 (55.0) | 11 019 (54.9) |
| Rural resident | 1474 (18.7) | 158 (20.2) | 1316 (18.6) | 879 (3.9) | 107 (4.5) | 772 (3.8) |
| Deprivation index quintile† | ||||||
| 1 (least deprived) | 951 (12.1) | 80 (10.2) | 871 (12.3) | 3357 (14.9) | 353 (14.8) | 3004 (15.0) |
| 2 | 1138 (14.5) | 105 (13.4) | 1033 (14.6) | 3811 (17.0) | 412 (17.2) | 3399 (16.9) |
| 3 | 1230 (15.6) | 108 (13.8) | 1122 (15.8) | 4140 (18.4) | 446 (18.7) | 3694 (18.4) |
| 4 | 1484 (18.8) | 134 (17.1) | 1350 (19.0) | 4652 (20.7) | 475 (19.9) | 4177 (20.8) |
| 5 (most deprived) | 2187 (27.8) | 222 (28.4) | 1965 (27.7) | 6275 (27.9) | 677 (28.3) | 5598 (27.9) |
| Unknown | 885 (11.2) | 134 (17.1) | 751 (10.6) | 226 (1.0) | 27 (1.1) | 199 (1.0) |
| Long-term care resident | 98 (1.2) | 24 (3.1) | 74 (1.0) | 516 (2.3) | 150 (6.3) | 366 (1.8) |
| Nonelective hospital admission in previous 12 mo | 1666 (21.2) | 290 (37.0) | 1376 (19.4) | 3183 (14.2) | 746 (31.2) | 2437 (12.1) |
| Nonelective hospital admission in previous 3 mo | 1016 (12.9) | 174 (22.2) | 842 (11.9) | 1576 (7.0) | 446 (18.7) | 1130 (5.6) |
| ED visit in previous 6 mo | 4782 (60.7) | 541 (69.1) | 4241 (59.8) | 13 096 (58.3) | 1551 (64.9) | 11 545 (57.5) |
| No. of ED visits in previous 6 mo, median (IQR) | 1 (1–2) | 2 (1–4) | 1 (1–2) | 0 (0–1) | 1 (0–2) | 0 (0–1) |
| SARS-CoV-2 strain | ||||||
| Wild type, original strain | 3018 (38.3) | 318 (40.6) | 2700 (38.1) | 8647 (38.5) | 1026 (42.9) | 7621 (38.0) |
| Alpha VOC | 1551 (19.7) | 110 (14.0) | 1441 (20.3) | 7059 (31.4) | 597 (25.0) | 6462 (32.2) |
| Delta VOC | 1429 (18.1) | 146 (18.6) | 1283 (18.1) | 867 (3.9) | 73 (3.1) | 794 (4.0) |
| Other VOC | 227 (2.9) | 8 (1.0) | 219 (3.1) | 1464 (6.5) | 129 (5.4) | 1335 (6.7) |
| Untested or indeterminate | 1650 (21.0) | 201 (25.7) | 1449 (20.4) | 4424 (19.7) | 565 (23.6) | 3859 (19.2) |
| Vaccination status | ||||||
| Fully vaccinated (≥ 2 doses) | 312 (4.0) | 63 (8.0) | 249 (3.5) | 312 (1.4) | 60 (2.5) | 252 (1.3) |
| Partially vaccinated (1 dose) | 407 (5.2) | 46 (5.9) | 361 (5.1) | 754 (3.4) | 194 (8.1) | 553 (2.8) |
| Unvaccinated | 7156 (90.9) | 674 (86.1) | 6482 (91.4) | 21 395 (95.3) | 2136 (89.4) | 19 266 (96.0) |
| Comorbidities from index hospital admission and admissions in previous year | ||||||
| Charlson comorbidity score, mean ± SD | 1.0 ± 1.6 | 1.8 ± 2.1 | 0.9 ± 1.5 | 0.4 ± 1.3 | 1.1 ± 2.1 | 0.3 ± 1.1 |
| Chronic pulmonary disease (COPD or asthma) | 593 (7.5) | 91 (11.6) | 502 (7.1) | 1693 (7.5) | 254 (10.6) | 1439 (7.2) |
| Heart failure or cardiomyopathy | 291 (3.7) | 60 (7.7) | 231 (3.3) | 1296 (5.8) | 335 (14.0) | 961 (4.8) |
| Hypertension | 933 (11.8) | 137 (17.5) | 796 (11.2) | 6220 (27.7) | 853 (35.7) | 5367 (26.7) |
| Diabetes mellitus | 2325 (29.5) | 271 (34.6) | 2054 (29.0) | 7103 (31.6) | 941 (39.4) | 6162 (30.7) |
| Coronary artery disease, including previous myocardial infarction, CABG surgery, PCI or stenting | 251 (3.2) | 41 (5.2) | 210 (3.0) | 1301 (5.8) | 272 (11.4) | 1029 (5.1) |
| Peripheral arterial disease | 46 (0.6) | 10 (1.3) | 36 (0.5) | 235 (1.0) | 66 (2.8) | 169 (0.8) |
| Cerebrovascular disease (including previous stroke or transient ischemic attack) | 96 (1.2) | 12 (1.5) | 84 (1.2) | 477 (2.1) | 92 (3.8) | 385 (1.9) |
| Atrial fibrillation or flutter | 314 (4.0) | 53 (6.8) | 261 (3.7) | 1425 (6.3) | 287 (12.0) | 1138 (5.7) |
| Ventricular arrythmias | 14 (0.2) | 1 (0.1) | 13 (0.2) | 61 (0.3) | 11 (0.5) | 50 (0.2) |
| Renal disease | 228 (2.9) | 51 (6.5) | 177 (2.5) | 939 (4.2) | 234 (9.8) | 705 (3.5) |
| Cancer | 214 (2.7) | 57 (7.3) | 157 (2.2) | 1076 (4.8) | 286 (12.0) | 790 (3.9) |
| Other lung disease (non-COPD or asthma) | 140 (1.8) | 43 (5.5) | 97 (1.4) | 375 (1.7) | 81 (3.4) | 294 (1.5) |
| Peptic ulcer disease | 47 (0.6) | 8 (1.0) | 39 (0.5) | 143 (0.6) | 41 (1.7) | 102 (0.5) |
| Liver disease | 171 (2.2) | 37 (4.7) | 134 (1.9) | 431 (1.9) | 81 (3.4) | 350 (1.7) |
| Dementia | 168 (2.1) | 46 (5.9) | 122 (1.7) | 1065 (4.7) | 295 (12.3) | 770 (3.8) |
Note: CABG = coronary artery bypass graft, COPD = chronic obstructive pulmonary disease, ED = emergency department, IQR = interquartile range, PCI = percutaneous coronary intervention, SD = standard deviation, VOC = variant of concern.
↵* Unless indicated otherwise.
↵† Results for Alberta are based on the Pampalon Deprivation Index and those for Ontario are based on the Ontario Marginalization Index.