Table 2.
Study characteristics
| Cohort | Number of Events | Number of patients | Person years | Mean age, years | Men, % | Mean FEV1%pred. | Mean mMRC | Past exacerbators, % | Mean no. prev. exacerbations | Current smoker, % | Mean BMI | Mean 6MWT, m | Mean SGRQ | Mean CAT |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COPDgene | 337 | 4484 | 10,603 | 63 (9) | 56 | 57.4 (22.8) | 1.5 | 0.16 | 43 | 27.9 (6.1) | 376.1 (124.1) | 36.9 (22.9) | ||
| Sevillaa | 205 | 596 | 1562 | 66 (10) | 95 | 43.5 (13.3) | 1 | 0.25 | 1.16 | 24 | 29.2 (5.7) | |||
| Copenhagenb | 186 | 2287 | 6618 | 61 (9) | 54 | 70.5 (23.7) | 1.3 | 71 | 25 (4.2) | |||||
| Genkols | 126 | 954 | 2708 | 65 (10) | 61 | 46.9 (17) | 1.3 | 0.15 | 0.6 | 47 | 25.4 (5) | |||
| Zaragoza IIa | 118 | 1150 | 3069 | 63 (9) | 93 | 62.3 (20.3) | 1.1 | 0.17 | 0.91 | 34 | 27.5 (4.8) | 356.2 (153.7) | ||
| HUNT | 116 | 1571 | 4583 | 63 (13) | 62 | 63.8 (18.7) | 1.3 | 47 | 26.4 (4.4) | |||||
| Galdakaoa | 92 | 543 | 1497 | 68 (8) | 96 | 55 (13.3) | 0.9 | 0 | 0.65 | 21 | 28.3 (4.4) | 408.9 (92.4) | ||
| Barmelweidb | 79 | 232 | 555 | 72 (9) | 60 | 45.2 (16.1) | 1.1 | 21 | 26 (6.3) | 363.4 (126.8) | ||||
| Terrassa IIIa | 78 | 181 | 423 | 72 (10) | 95 | 45.2 (14.4) | 1.2 | 0.31 | 1.28 | 23 | 27.9 (5) | 330.4 (105.8) | ||
| Initiatives BPCO | 76 | 930 | 1525 | 64 (10) | 77 | 52.4 (20.3) | 1.1 | 0.4 | 1.65 | 28 | 25.4 (5.5) | 387.4 (120.8) | 43.9 (19) | |
| Terrassa Ia | 72 | 135 | 284 | 72 (9) | 92 | 41.3 (13) | 1.3 | 0.25 | 1.03 | 17 | 26.3 (4.9) | |||
| SEPOCb | 61 | 318 | 871 | 65 (9) | 100 | 45 (18.3) | 1.5 | 38 | 26.4 (4.2) | |||||
| Requena IIa,c | 52 | 186 | 396 | 71 (9) | 99 | 44.5 (16.5) | 1 | 0.16 | 0.62 | 17 | 28.1 (5.2) | 380.1 (111.9) | ||
| ICE COLD ERIC | 47 | 400 | 1071 | 67 (10) | 57 | 55.3 (16.5) | 1.5 | 0.13 | 0.58 | 39 | 26.1 (5.2) | |||
| PAC-COPDb | 41 | 342 | 980 | 68 (9) | 93 | 52.4 (16.2) | 1 | 0.04 | 33 | 28.2 (4.7) | 435.5 (90.6) | |||
| Tenerifea | 34 | 275 | 653 | 63 (10) | 79 | 55.8 (21.2) | 1.2 | 0.06 | 0.37 | 42 | 27.3 (5.1) | 487.4 (87.5) | ||
| Terrassa IIa | 28 | 66 | 145 | 72 (9) | 98 | 30.2 (12.9) | 1 | 0.42 | 1.81 | 14 | 25.7 (4.3) | 217.7 (76.6) | ||
| Requena Ia | 23 | 174 | 393 | 72 (9) | 99 | 48.1 (16.8) | 1.2c | 0.03 | 0.22 | 23 | 28 (4.2) | 434.4 (125.3) | ||
| Zaragoza Ia | 21 | 137 | 379 | 66 (8) | 99 | 49.8 (17.6) | 1.1 | 27 | 27.7 (4.6) | 449 (91.9) | ||||
| Son Espases Mallorca | 17 | 115 | 292 | 70 (7) | 79 | 41.5 (13.4) | 1 | 0.59 | 27 | 27.1 (5.9) | 401.5 (89.7) | 16.6 (8.2) | ||
| Basqueb | 16 | 106 | 299 | 71 (9) | 98 | 46.9 (11.4) | 0.6 | 23 | 26.1 (4.9) | 442.9 (95.4) | ||||
| Japan | 15 | 147 | 409 | 69 (7) | 100 | 47.1 (17.5) | 0.9 | 22 | 21 (2.9) | 36.6 (16.5) | ||||
| La Princesa Madrid | 11 | 318 | 633 | 71 (10) | 74 | 50 (19.8) | 1.1 | 0.18 | 0.77 | 19 | 26.2 (5.1) | 337.1 (92.8) | ||
| Pamplonaa | 7 | 190 | 470 | 65 (8) | 84 | 68.9 (19.9) | 1.1 | 37 | 27 (4.4) | 463.2 (113.9) | ||||
| Mar de Plata Argentina | 3 | 99 | 147 | 64 (9) | 60 | 48.8 (18.6) | 1 | 0.29 | 21 | 27 (5.6) | 353.2 (128.7) | 16.1 (7.8) | ||
| A1ATDd | 0 | 308 | 834 | 58 (10) | 60 | 53.1 (25.1) | 1.2 | 0.52 | 5 | 25.7 (4.9) | 50.8 (19.9) | 20.5 (8.1) |
Abbreviations: FEV1% pred. forced expiratory volume in 1 s percentage predicted, mMRC modified Medical Research Council (MMRC) dyspnea scale; past exacerbators are defined as patients with more than one exacerbation in the previous year; mean number previous exacerbations are referred to the previous year, BMI body mass index, 6MWT 6-min walk test, SGRQ Saint George’s Respiratory Questionnaire, CAT COPD Assessment Test
The cohorts are presented in decreasing order of number of events. Most of the variables available provided by the 3CIA collaboration for the different cohorts are shown. In particular, we show all the variables constituting the scores analyzed in our study. We present the standard deviation for all individual variables whose distribution is approximately normal; this is not the case for count (with small numbers) or categorical variables, like number of previous exacerbations or mMRC)
aCohorts belonging to the Collaborative Cohorts to Assess Multicomponent Indices of COPD in Spain (COCOMICS) collaboration
bCohorts belonging to the ADO collaboration. For information concerning the cohorts, see [49]
cSince none of the scores could be evaluated in the cohort Requena I (mainly because the variable dyspnoea was missing for 95% of the patients, i.e., for 165 out of 174 patients), this cohort was excluded from the analysis
dSince there was no event in a follow-up of 3 years, the cohort A1ATD was excluded from the analysis
Missing cells correspond to variables that are completely missing in the cohort of the correspondent row