Baseline characteristics of patients with confirmed laboratory COVID-19 in a Korean nationwide cohort (N=4785)
| Characteristic | Entire cohort | Patients with confirmed laboratory COVID-19 | ||
| None | Current use of PPI | Past use of PPI | ||
| Total, N (%) | 4785 | 4233 | 364 | 188 |
| Age, years, mean (SD) | 45.4 (18.8) | 44.4 (18.8) | 53.8 (16.9) | 52.4 (17.6) |
| Sex, n (%) | ||||
| Male | 2103 (44.0) | 1893 (44.7) | 135 (37.1) | 75 (39.9) |
| Female | 2682 (56.1) | 2340 (55.3) | 229 (62.9) | 113 (60.1) |
| Region of residence, n (%) | ||||
| Rural | 2367 (49.5) | 2096 (49.5) | 184 (50.6) | 87 (46.3) |
| Urban | 2418 (50.5) | 2137 (50.5) | 180 (49.5) | 101 (53.7) |
| History of diabetes mellitus, n (%) | 524 (11.0) | 435 (10.3) | 57 (15.7) | 32 (17.0) |
| History of cardiovascular disease, n (%) | 263 (5.5) | 209 (4.9) | 35 (9.6) | 19 (10.1) |
| History of cerebrovascular disease, n (%) | 272 (5.7) | 203 (4.8) | 47 (12.9) | 22 (11.7) |
| History of COPD, n (%) | 185 (3.9) | 142 (3.4) | 31 (8.5) | 12 (6.4) |
| History of asthma, n (%) | 338 (7.1) | 269 (6.4) | 44 (12.1) | 25 (13.3) |
| History of hypertension, n (%) | 945 (19.8) | 771 (18.2) | 118 (32.4) | 56 (29.8) |
| History of chronic kidney disease, n (%) | 150 (3.1) | 113 (2.7) | 25 (6.9) | 12 (6.4) |
| Charlson Comorbidity Index, n (%) | ||||
| 0 | 3431 (71.7) | 3148 (74.4) | 180 (49.5) | 103 (54.8) |
| 1 | 439 (9.2) | 356 (8.41) | 61 (16.8) | 22 (11.7) |
| ≥2 | 915 (19.1) | 729 (17.2) | 123 (33.8) | 63 (33.5) |
| Current use of medication, n (%) | ||||
| Systemic steroid | 1030 (21.5) | 848 (20.0) | 131 (36.0) | 51 (27.1) |
| Metformin | 315 (6.6) | 252 (6.0) | 48 (13.2) | 15 (8.0) |
| Aspirin | 166 (3.5) | 122 (2.9) | 29 (8.0) | 15 (8.0) |
COPD, chronic obstructive pulmonary disease; PPI, proton pump inhibitor.