Table 1.
Subject demographics, pulmonary function and imaging measurements
| Parameter (±SD unless specified) | Never-smoker (n=286) | At-risk (n=297) | GOLD I (n=361) | GOLD II + (n=239) |
| Subject demographic | ||||
| Age, years | 66 (10) | 66 (9.1) | 68 (10)† | 66 (11) |
| Female sex, n (%) | 136 (48) | 131 (44) | 124 (34)*† | 100 (42) |
| Caucasian, n (%) | 266 (93) | 282 (95) | 347 (96) | 223 (93) |
| Pack-years, years | 0 (0) | 21 (24)* | 18 (23)* | 26 (26)*†‡ |
| BMI, kg/m2 | 27 (4.6) | 28 (5.1) | 27 (4.5) | 28 (6.2) |
| Current-smoker, n (%) | – | 64 (22) | 52 (14)† | 61 (26) |
| History of asthma, n (%) | 21 (7.3) | 30 (10) | 66 (18)*† | 86 (36)*†‡† |
| History of tuberculosis, n (%) | 3 (1.0) | 0 (0.0) | 5 (1.4) | 5 (2.1)† |
| History of HDHTDM, n (%) | 97 (34) | 105 (35) | 131 (36) | 115 (48)*†‡ |
| History of bronchiectasis, n (%) | 54 (19) | 47 (17) | 75 (21) | 48 (20) |
| Pulmonary function | ||||
| FEV1, %pred | 106 (15) | 103 (14)* | 96 (12)*† | 69 (8.0)*†‡ |
| FEV1/FVC, % | 78 (4.7) | 77 (4.6) | 64 (4.6)*† | 59 (7.5)*†‡ |
| RV/TLC, % | 37 (7.6) | 37 (7.3) | 40 (8.9)*† | 46 (9.3)*†‡ |
| DLCO, %pred | 115 (23) | 113 (22) | 109 (23)* | 95 (24)*†‡ |
| Chronic cough, n (%) | 22 (7.6) | 43 (14)* | 52 (14)* | 64 (27)*†‡ |
| BDR FEV1, % | 3.7 (6.1) | 3.4 (5.9) | 6.6 (1.8)*† | 10 (12)*†‡ |
| BDR responder, n (%) | 28 (10) | 32 (11) | 99 (27)*† | 100 (42)*†‡ |
| Imaging | ||||
| LAA856, % | 21 (17) | 18 (15) | 29 (16)*† | 31 (19)*† |
| LAA950, % | 3.0 (2.9) | 3.0 (3.2) | 5.4 (4.9)*† | 5.3 (5.0)*† |
| TAC, n | 221 (73) | 217 (68) | 190 (66)*† | 152 (53)*†‡ |
| Pi10, mm | 3.9 (0.15) | 3.9 (0.13) | 3.9 (0.13) | 3.9 (0.12) |
| Inner area, mm2 | 12 (4.6) | 12 (3.2) | 11 (3.1)*† | 9.5 (2.6)*†‡ |
| Wall area per cent, % | 62 (2.9) | 62 (2.8) | 63 (3.0)† | 64 (2.6)*†‡ |
| DPMfSAD, % | 41 (17) | 37 (17) | 42 (13)*† | 49 (15)*†‡ |
| PRMfSAD, % | 21 (12) | 15 (13) | 29 (15)*† | 29 (17)*† |
Significance of difference (p<0.05).
*Significantly different from never-smoker.
†Significantly different from at risk.
‡Significantly different from GOLD I.
BDR, bronchodilator response; BMI, body mass index; DLCO, diffusing capacity for carbon monoxide; DPM, disease probability measure; FEV1, forced expiratory volume in 1 s; fSAD, functional small airway disease; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; HDHTDM, heart disease, systemic hypertension or diabetes mellitus; LAA856, low attenuation area of the lung with attenuation values below -856 HU on full-expiration CT; %pred, per cent predicted; PRM, parametric response mapping; RV, residual volume; TAC, total airway count; TLC, total lung capacity.