Characteristics of included coronavirus disease 2019 (COVID-19) population
| Characteristics | Asthma | COPD | No asthma or COPD | p-value |
| Subjects n | 354 | 432 | 4318 | |
| Age median (IQR) | 47.5 (24.1) | 76.8 (13.7) | 53.0 (30.0) | <0.001 |
| Age groups | <0.001 | |||
| <65 years | 291 (82.2) | 73 (16.9) | 3036 (70.3) | |
| 65–74 years | 30 (8.5) | 118 (27.3) | 495 (11.5) | |
| ≥75 years | 33 (9.3) | 241 (55.8) | 787 (18.2) | |
| Female sex | 217 (61.3) | 220 (50.9) | 2268 (52.5) | |
| Household income | <0.004 | |||
| Lowest quartile | 79 (22.3) | 154 (35.6) | 1043 (24.1) | |
| Second lowest quartile | 75 (21.2) | 176 (40.7) | 1025 (23.7) | |
| Second highest quartile | 95 (26.8) | 75 (17.4) | 1106 (25.6) | |
| Highest quartile | 105 (29.7) | 27 (6.2) | 1144 (26.5) | |
| Highest completed education | <0.001 | |||
| Upper or lower secondary school | 85 (24.0) | 188 (43.5) | 1096 (25.4) | |
| Vocational upper secondary school | 108 (30.5) | 182 (42.1) | 1616 (37.4) | |
| Medium-cycle higher education or bachelors' degree | 109 (30.8) | 49 (11.3) | 1100 (25.5) | |
| Long-cycle higher education | 52 (14.7) | 13 (3.0) | 506 (11.7) | |
| Civil status | ||||
| Single | 116 (32.8) | 217 (50.2) | 1544 (35.8) | <0.001 |
| Married or cohabiting | 238 (67.2) | 215 (49.8) | 2774 (64.2) | |
| Origin | ||||
| Danish | 281 (79.4) | 392 (90.7) | 3518 (81.5) | <0.001 |
| Immigrants or immigrants' descendants | 73 (20.6) | 40 (9.3) | 800 (18.5) | |
| Comorbidities | ||||
| Ischaemic heart disease | 10 (2.8) | 98 (22.7) | 271 (6.3) | <0.001 |
| Previous myocardial infarction | 9 (2.5) | 96 (22.2) | 232 (5.4) | <0.001 |
| Heart failure | 7 (2.0) | 83 (19.2) | 147 (3.4) | <0.001 |
| Atrial fibrillation or flutter | 27 (7.6) | 139 (32.2) | 474 (11.0) | <0.001 |
| Cerebral vascular disease | 13 (3.7) | 91 (21.1) | 276 (6.4) | <0.001 |
| Diabetes | 34 (9.6) | 109 (25.2) | 455 (10.5) | <0.001 |
| Chronic kidney disease | 7 (2.0) | 63 (14.6) | 214 (5.0) | <0.001 |
| Blood eosinophil count# ×109 cells·L−1 mean±sd | 0.17±0.21 | 0.15±0.14 | 0.13±0.17 | <0.001 |
| Treatment¶ | ||||
| Short-acting β-agonists | 112 (31.6) | 169 (39.1) | 98 (2.3) | <0.001 |
| Long-acting β-agonists | 130 (36.7) | 260 (60.2) | 23 (0.5) | <0.001 |
| Long-acting muscarinergic antagonists | 17 (4.8) | 200 (46.3) | 10 (0.2) | <0.001 |
| Inhaled corticosteroids | 178 (50.3) | 187 (43.3) | 40 (0.9) | <0.001 |
| Leukotriene receptor antagonists | 42 (11.9) | 12 (2.8) | 0 (0) | <0.001 |
| Antihistamines | 67 (18.9) | 47 (10.9) | 261 (6.0) | <0.001 |
| Systemic corticosteroids | 41 (11.6) | 90 (20.8) | 156 (3.6) | <0.001 |
Data are presented as n (%) unless otherwise stated. Total n=5104. IQR: interquartile range. #: out of the total population, 2923 patients with COVID-19 had blood eosinophil counts within the last 5 years. ¶: frequency of different types of medication from the last 12 months were estimated; if a patient received combination therapy, for example inhaled corticosteroids and a long-acting β-agonist, the medications were split up into their generic forms; treatment with systemic corticosteroids was defined as any prescription filled within the last 12 months.