Table 1:
Descriptive statistics of included participants by mean (SD), N 563 (%), or median [IQR].
| Covariate | Total (N=4484) |
COPD1 (N=1966) |
PRISm2 (N=540) |
Normal3 (N=1978) |
|---|---|---|---|---|
| Demographics | ||||
| Age, years | 65.4 (8.43) | 68.0 (8.08) | 62.8 (8.15) | 63.6 (8.15) |
| Female (%) | 2303 (51.4%) | 901 (45.8%) | 311 (57.6%) | 1091 (55.2%) |
| White Race (%) | 3273 (73.0%) | 1540 (78.3%) | 342 (63.3%) | 1391 (70.3%) |
| BMI, kg/m^2 | 28.9 (6.26) | 27.9 (6.15) | 31.8 (7.12) | 29.1 (5.85) |
| Current Smoker (%) | 1636 (36.5%) | 665 (33.8%) | 238 (44.1%) | 733 (37.1%) |
| Smoking History, pack-years | 43.4 (23.1) | 50.3 (24.4) | 41.3 (22.3) | 37.0 (19.7) |
| Lung function and O2 use | ||||
| FEV1/FVC ratio | 0.68 (0.15) | 0.54 (0.12) | 0.76 (0.05) | 0.78 (0.05) |
| DLCO, % predicted | 78.3 (22.7) | 66.8 (22.3) | 78.6 (18.8) | 89.0 (18.4) |
| FEV1, % predicted | 78.8 (24.2) | 62.0 (22.6) | 70.5 (7.6) | 97.8 (11.7) |
| Baseline SpO2, % | 96.1 (2.76) | 95.3 (3.34) | 96.5 (2.09) | 96.9 (1.94) |
| Supplemental O2 Use (%) | 488 (10.9%) | 425 (21.6%) | 23 (4.3%) | 40 (2.0%) |
| Medication use (%) | ||||
| Current COPD Medication Use | 1789 (39.9%) | 1246 (63.4%) | 199 (36.9%) | 344 (17.4%) |
| LAMA Use | 528 (12.8%) | 440 (24.7%) | 44 (8.9%) | 44 (2.4%) |
| LABA Use | 653 (15.9%) | 509 (28.6%) | 68 (13.7%) | 76 (4.1%) |
| ICS Use | 917 (22.3%) | 701 (39.4%) | 92 (18.5%) | 124 (6.7%) |
| Oral beta-blocker4 | 572 (12.8%) | 287 (14.6%) | 83 (15.4%) | 202 (10.2%) |
| Non-dihydro. Ca. channel blocker4 | 77 (1.7%) | 55 (2.8%) | 4 (0.7%) | 18 (0.9%) |
| Comorbidities (%) | ||||
| Coronary Artery Disease | 353 (7.9%) | 195 (9.9%) | 43 (8.0%) | 115 (5.8%) |
| Diabetes | 748 (16.7%) | 312 (15.9%) | 143 (26.5%) | 293 (14.8%) |
| Hypertension | 2242 (50.0%) | 1038 (52.8%) | 314 (58.1%) | 890 (45.0%) |
| Hyperlipidemia | 2020 (45.0%) | 904 (46.0%) | 263 (48.7%) | 853 (43.1%) |
| Congestive Heart Failure | 117 (2.6%) | 71 (3.6%) | 19 (3.5%) | 27 (1.4%) |
| Peripheral Vascular Disease | 124 (2.8%) | 77 (3.9%) | 16 (3.0%) | 31 (1.6%) |
| Physiologic Variables | ||||
| 6-minute walk test distance, ft | 1339 (393.3) | 1237 (401.6) | 1272 (359.8) | 1457 (360.0) |
| Resting HR, beats per minute | 73.3 (12.2) | 74.6 (12.4) | 74.0 (12.6) | 71.7 (11.6) |
| HR post 6-minute walk test, beats per minute | 98.2 (18.5) | 98.1 (18.2) | 97.1 (18.5) | 98.7 (18.7) |
| Chronotropic Index | 0.30 [0.18, 0.43] | 0.30 [0.17, 0.43] | 0.27 [0.16, 0.39] | 0.31 [0.19, 0.45] |
| Heart Rate Recovery, beats per minute | 12 [6, 20] | 11 [5, 19] | 12 [6, 20] | 13 [7, 21] |
| Follow up and event rates | ||||
| Years of follow-up data | 4.1 (1.4) | 4.1 (1.4) | 4.0 (1.4) | 4.2 (1.3) |
| Rate of Events, events/yr | 0.34 | 0.52 | 0.31 | 0.17 |
| Rate of Severe Events, events/yr | 0.14 | 0.21 | 0.15 | 0.07 |
| Died during follow-up (%) | 388 (8.7%) | 277 (14.1%) | 35 (6.5%) | 76 (3.8%) |
BMI, body mass index; COPD, chronic obstructive pulmonary disease; DLCO, diffusing capacity for carbon monoxide; FEV1, forced expiratory volume in 1-second; FVC, forced vital capacity; HR, heart rate; ICS, inhaled corticosteroid; LABA, long acting beta-agonist; LAMA, long acting muscarinic antagonist; O2, oxygen; PRISm, preserved ratio impaired spirometry; SpO2, pulse oximetry saturation.
COPD was defined as an FEV1/FVC ratio < 0.7.
PRISm was defined as an FEV1/FVC ratio ≥ 0.7 and an FEV1 < 80% predicted
Normal spirometry was defined as an FEV1/FVC ratio ≥ 0.7 and FEV1 ≥ 80% predicted
Comprehensive medication data was only collected on the first 5000 participants at the year 5 visit. Data on beta-blocker use and non-dihydropyridine calcium channel blocker use was missing for 1250 (27.9%) participants.