Table 1.
Participant characteristics by chronic obstructive pulmonary disease group
| Variables | COPD Groups [n (%)] or [median (IQR)] |
||
|---|---|---|---|
| No COPD (n = 426) | Undiagnosed COPD (n = 377) | Known COPD (n = 183) | |
| Age, yr | 65 (62,68) | 66 (63,69) | 66 (63–70) |
| Female | 213 (50.0) | 142 (37.7) | 93 (50.8) |
| Ethnicity | |||
| White | 324 (76.1) | 320 (84.9) | 171 (93.4) |
| Black/African/Caribbean | 62 (14.5) | 31 (8.2) | 7 (3.8) |
| Other | 40 (9.2) | 24 (6.3) | 5 (2.7) |
| Highest level of education | |||
| Left school at or before age 15 yr | 207 (48.6) | 187 (49.6) | 121 (66.1) |
| Completed high school level or equivalent | 45 (10.6) | 41 (10.9) | 18 (9.8) |
| A-levels or equivalent | 44 (10.3) | 41 (10.9) | 11 (6.0) |
| Further education | 23 (5.4) | 15 (4.0) | 9 (4.9) |
| Bachelor’s degree | 51 (12.0) | 53 (14.1) | 15 (8.2) |
| Further higher degree | 46 (10.8) | 36 (9.6) | 4 (2.2) |
| Other/prefers to say | 10 (2.4) | 4 (1.1) | 5 (2.7) |
| Index of multiple deprivation quintile | |||
| 1 (most deprived) | 239 (56.1) | 199 (52.8) | 99 (54.1) |
| 2 | 136 (31.9) | 141 (37.4) | 60 (32.8) |
| 3 | 12 (2.8) | 6 (1.6) | 2 (1.1) |
| 4 | 1 (0.23) | 1 (0.3) | 0 (0) |
| 5 (least deprived) | 0 (0) | 0 (0) | 0 (0) |
| Missing | 38 (8.9) | 30 (12.0) | 22 (12.02) |
| Smoking history | |||
| Current | 288 (67.6) | 252 (66.8) | 121 (66.1) |
| Former smoker | 138 (32.3) | 125 (33.2) | 62 (33.9) |
| Years smoked, yr | 46 (41–50) | 47 (42–52) | 48 (45–54) |
| Average smoking intensity, cigarettes/d | 15 (10–20) | 15 (10–20) | 20 (15–25) |
| Lung function | |||
| FEV1, L | 2.29 (1.86–2.72) | 2.03 (1.64–2.54) | 1.57 (1.18–1.95) |
| FEV1 % predicted | 91 (79–103) | 79.0 (65–91) | 65 (50–80) |
| FVC, L | 2.97 (2.39–3.36) | 3.33 (2.68–4.01) | 2.75 (2.18–3.48) |
| FVC % predicted | 94 (81–107) | 100 (85–115) | 91 (73–108) |
| FEV1:FVC, % | 76.5 (73–80) | 64 (59–68) | 58 (50–64) |
| BMI, kg/m2 | 26.8 (23.6–30.1) | 25.2 (22.5–28.6) | 25.6 (22–29.1) |
| mMRC dyspnea score | |||
| 0-Breathless on strenuous exercise only | 310 (72.7) | 254 (67.4) | 68 (37.2) |
| 1-Slightly breathless, e.g., up hills | 103 (24.2) | 110 (29.2) | 88 (48.1) |
| 2-Slower than contemporaries | 11 (2.6) | 9 (2.4) | 21 (11.5) |
| 3-100 m exercise tolerance | 1 (0.2) | 4 (1.1) | 6 (3.3) |
| 4-Housebound | 1 (0.2) | 0 (0) | 0 (0) |
| LDCT performed | 317 (74.4) | 297 (78.8) | 147 (80.3) |
Definition of abbreviations: BMI = body mass index; COPD = chronic obstructive pulmonary disease; FEV1 = forced expiratory volume in 1 second; FVC = forced vital capacity; IQR = interquartile range; LDCT = low-dose computed tomography; LHC = lung health check; mMRC = modified Medical Research Council Dyspnea scale.
COPD groups based on prebronchodilator spirometry at LHC appointment pre-LDCT: “no COPD” (FEV1:FVC at LHC ≥70%); “undiagnosed COPD” (FEV1:FVC at LHC <70% and no reported history of COPD); and “known COPD” (FEV1:FVC at LHC <70% and a reported history of COPD). Percent totals may not sum up due to rounding.