TABLE 1.
Baseline characteristics of patients
| Total | COVID-19 cohort | Matched cohort | p-value | |
| Patients | 129 120 | 8070 | 121 050 | |
| Age years | 0.999 | |||
| <10 | 1296 (1.0) | 81 (1.0) | 1215 (1.0) | |
| 10–19 | 4416 (3.4) | 276 (3.4) | 4140 (3.4) | |
| 20–29 | 32 912 (25.5) | 2057 (25.5) | 30 855 (25.5) | |
| 30–39 | 13 312 (10.3) | 832 (10.3) | 12 480 (10.3) | |
| 40–49 | 16 576 (12.8) | 1036 (12.8) | 15 540 (12.8) | |
| 50–59 | 25 072 (19.4) | 1567 (19.4) | 23 505 (19.4) | |
| 60–69 | 19 184 (14.9) | 1199 (14.9) | 17 985 (14.9) | |
| 70–79 | 9872 (7.7) | 617 (7.7) | 9255 (7.7) | |
| ≥80 | 6480 (5.0) | 405 (5.0) | 6075 (5.0) | |
| Sex | 0.999 | |||
| Male | 51 776 (40.1) | 3236 (40.1) | 48 540 (40.1) | |
| Female | 77 344 (59.9) | 4834 (59.9) | 72 510 (59.9) | |
| Type of insurance | <0.001 | |||
| Self-employed health insurance | 36 978 (28.6) | 2271 (28.1) | 34 707 (28.7) | |
| Employee health insurance | 87 095 (67.5) | 5212 (64.6) | 81 883 (67.6) | |
| Medical aid | 5047 (3.9) | 587 (7.3) | 4460 (3.7) | |
| Comorbidities | ||||
| ILD | 488 (0.4) | 67 (0.8) | 421 (0.4) | <0.001 |
| CTD-related ILD | 87 (0.1) | 13 (0.2) | 74 (0.1) | 0.001 |
| Biologics used | 3 (0.00) | 0 | 3 (0.00) | 0.999 |
| Biologics not used | 84 (0.1) | 13 (0.2) | 71 (0.1) | 0.001 |
| CTD-unrelated ILD | 401 (0.3) | 54 (0.7) | 347 (0.3) | <0.001 |
| IPF | 101 (0.1) | 14 (0.2) | 87 (0.1) | 0.002 |
| Sarcoidosis | 2 (0.00) | 0 | 2 (0.00) | 0.999 |
| Hypersensitivity pneumonitis | 11 (0.01) | 2 (0.02) | 9 (0.01) | <0.001 |
| Others | 287 (0.2) | 38 (0.5) | 249 (0.2) | <0.001 |
| Lung cancer | 362 (0.3) | 37 (0.5) | 325 (0.3) | 0.002 |
| Hypertension | 28 895 (22.4) | 1934 (24.0) | 26 961 (22.3) | <0.001 |
| Diabetes mellitus | 21 895 (17.0) | 1632 (20.2) | 20 263 (16.7) | <0.001 |
| Cerebrovascular diseases | 9482 (7.3) | 687 (8.5) | 8795 (7.3) | <0.001 |
| Angina pectoris | 6046 (4.7) | 424 (5.3) | 5622 (4.6) | 0.012 |
| Myocardial infarction | 954 (0.7) | 101 (1.3) | 853 (0.7) | <0.001 |
| Heart failure | 3985 (3.1) | 357 (4.4) | 3628 (3.0) | <0.001 |
| CTD | 5849 (4.5) | 461 (5.7) | 5388 (4.5) | <0.001 |
| Malignancy other than lung cancer | 6930 (5.4) | 426 (5.3) | 6504 (5.4) | 0.716 |
Data are presented as n or n (%), unless otherwise stated. ILD: interstitial lung disease; CTD: connective tissue disease; IPF: idiopathic pulmonary fibrosis.