Table 1.
Demographic data, functional parameters, and low-attenuation (LAA) percentages, for the pretext self-supervised contrastive task, for the generative model on the “control” class from the COPDGene dataset, and for the internal (COPDGene) and external test set (COSYCONET). Note: Attenuation percentages were measured by different methods: VIDA Diagnostics for COPDGene, YACTA for COSYCONET
| Characteristic | Training pretext task (COPDGene) (“normal” and “diseased” class) |
Training generative model (COPDGene) (only “normal” class) |
Internal test set (COPDGene) (“normal” and “diseased” classes) |
External test set (COSYCONET) (“normal” and “diseased” classes) |
|---|---|---|---|---|
| Demographic data | ||||
| N of patients [N] | 3144 | 1373 | 1310 | 446 |
| M [N] | 1699 | 694 | 692 | 272 |
| F [N] | 1445 | 679 | 618 | 174 |
| Age (y) [mean, (IQR)] | 63 (55–69) | 60 (52–66) | 63 (56–69) | 63 (58–69) |
| BMI [mean, (SD)] † | 28.3 (5.7) | 29.1 (5.6) | 28.1 (5.7) | 26.6 (4.6) |
| Smoking habits | ||||
| Never-smoker [N, (%)] | 63 (2.0%) | 63 (4.6%) | 29 (2.2%) | 34 (7.6%) |
| Former smoker [N, (%)] | 1862 (59.2%) | 755 (54.9%) | 817 (62.4%) | 298 (66.7%) |
| Current smokers [N, (%)] | 1219 (38.8%) | 555 (40.4%) | 464 (35.4%) | 114 (25.6%) |
| Smoking duration (y) [mean, (SD)] † | 36 (12) | 31 (13) | 36 (12) | 33 (15) |
| Spirometry | ||||
| FEV1%_pred [mean, (SD)] | 75.4 (26.8) | 97.2 (11.3) | 74.2 (27.1) | 57.6 (19.1) |
| FEV1/FVC [mean, (SD)] | 0.6 (0.2) | 0.8 (0.1) | 0.6 (0.2) | 0.7 (0.2) |
| Non-smoker control [N] | 63 | 63 | 29 | 0 |
| GOLD 0 [N] | 1310 | 1310 | 538 | 23 |
| GOLD 1 [N] | 350 | 0 | 128 | 30 |
| GOLD 2 [N] | 764 | 0 | 315 | 215 |
| GOLD 3 [N] | 423 | 0 | 195 | 146 |
| GOLD 4 [N] | 234 | 0 | 105 | 32 |
| Severe exacerbations [N (%)] | 318 (10.1%) | 40 (3%) | 137 (10.5%) | 224 (50.3%) |
| 6MWT (ft) [mean, (SD)] *+#† | 433.8 (120.7) | 485.4 (98.6) | 427.1 (124.8) | 453.3 (99.8) |
| SGRQ [mean, (SD)] † | 25.6 (22.5) | 13.3 (15.5) | 25.9 (22.9) | 40.3 (18.8) |
| mMRC dyspnea score 0 [N] *#† | 1502 | 963 | 588 | 274 |
| mMRC dyspnea score 1 [N] *#† | 460 | 193 | 221 | 110 |
| mMRC dyspnea score 2 [N] *#† | 364 | 104 | 158 | 60 |
| mMRC dyspnea score 3 [N] *#† | 549 | 98 | 225 | 1 |
| mMRC dyspnea score 4 [N] *#† | 264 | 15 | 115 | 0 |
| Imaging | ||||
| Imaging (Insp and Exp) | ||||
| LAA-950%* [mean, (SD)] *+# | 7.8 (10.4) | 2.5 (3.0) | 8.1 (10.6) | 17.0 (13.6) |
| LAA-856%* [mean, (SD)] *+# | 25.4 (20.4) | 11.7 (9.9) | 26.1 (21.1) | 45.2 (20.5) |
COPDGene, Genetic Epidemiology of COPD; COSYCONET, COPD and SYstemic consequences-COmorbidities NETwork; N, number; SD, standard deviation; y, years; BMI, body mass index; FEV1, forced expiratory volume in 1 s; FEV1/FVC, FEV1-to-forced vital capacity ratio; GOLD, Global Initiative for Chronic Obstructive Lung Disease; 6MWT, 6-min walking test; SGRQ, St. George’s Respiratory Questionnaire; LAA-950%, percentage of LAA under − 950 HU; LAA-856%, percentage of LAA under − 856 HU
For some cases, data was not available:
*(48 for 6MWT, 5 for mMRC dyspnea score, 7 for LAA-950%, 163 for LAA-856%);
+(7 for 6MWT, 3 for LAA-950%, 65 for LAA-856%);
#(17 for 6MWT, 3 for mMRC dyspnea score, 3 for LAA-950%, 76 for LAA-856%);
†(1 for BMI, 3 smoking duration, 22 for 6MWT, 2 for SGRQ, 1 for mMRC dyspnea score)