Presentation of the pulmonary outcomes at the 3- and 12-month follow-up visits after hospital discharge for COVID-19
| 3-month visit | 12-month visit | ||||
| n | n | p-value | |||
| Self-reported dyspnoea | 204 | 211 | 0.25 | ||
| mMRC 0 | 99 (48) | 107 (51) | |||
| mMRC 1 | 64 (31) | 70 (33) | |||
| mMRC ≥2 | 41 (20) | 34 (16) | |||
| Exercise capacity | |||||
| 6MWD m | 190 | 542±123 | 174 | 570±109 | 0.01 |
| 6MWD % predicted | 185 | 99±21 | 174 | 114±33 | <0.001 |
| 6MWD <LLN | 190 | 5 (3) | 174 | 8 (5) | 0.02 |
| Spirometry | |||||
| FVC L | 244 | 3.8±1.1 | 221 | 3.9±1.1 | 0.30 |
| FVC % predicted | 244 | 95±14 | 221 | 96±14 | 0.06 |
| FVC <LLN | 244 | 21 (9) | 221 | 18 (8) | 0.81 |
| FEV1 L | 244 | 2.9±0.9 | 221 | 3.9±1.1 | 0.62 |
| FEV1 % predicted | 244 | 93±16 | 221 | 94±15 | 0.10 |
| FEV1 <LLN | 244 | 28 (11) | 221 | 17 (8) | 0.13 |
| Diffusion capacity of the lungs | |||||
| DLCO mmol min−1 kPa−1 | 242 | 7.3±2.2 | 218 | 7.6±2.1 | <0.001 |
| DLCO % predicted | 241 | 87±18 | 213 | 91±16 | <0.001 |
| DLCO <LLN | 242 | 61 (25) | 218 | 38 (17) | <0.001 |
| DLCO 60–79% predicted | 241 | 45 (19) | 216 | 24 (11) | <0.001 |
| DLCO 40–59% predicted | 15 (6) | 9 (4) | |||
| DLCO <40% predicted | 3 (1) | 0 | |||
| Body plethysmography | |||||
| TLC L | 214 | 5.9±1.5 | 177 | 6.1±1.5 | 0.03 |
| TLC % predicted | 202 | 92±15 | 166 | 94±15 | 0.02 |
| TLC <LLN | 214 | 51 (24) | 177 | 40 (23) | 0.64 |
| Chest CT | |||||
| Any GGO | 241 | 112 (46) | |||
| GGO >10% | 241 | 43 (18) | |||
| Fibrotic-like findings | 241 | 96 (40) | |||
| Chest CT at both time points | |||||
| Any GGO | 124 | 89 (72) | 124 | 62 (50) | <0.001 |
| GGO >10% | 124 | 39 (31) | 124 | 10 (8) | < 0.001 |
| Fibrotic-like findings | 124 | 81 (65) | 124 | 74 (60) | 0.16 |
Data are presented as n (%) or mean±sd unless otherwise stated. Paired t-test for continuous variables, Wilcoxon sign rank test for ordinal variables, and McNemar's test for categorical variables. mMRC: modified Medical Research Council dyspnoea scale; 6MWD: 6-min walk distance; LLN: lower limit of normal; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; DLCO: diffusion capacity of the lungs for carbon monoxide; TLC: total lung capacity; CT: computed tomography; GGO: ground-glass opacities; GGO >10%: >10% GGO in at least one lung zone; sd: standard deviation.