Table 1.
Demographic characteristics
| GOLD stage | Stage I N=43 |
Stage II N=167 |
Stage III N=362 |
Stage IV N=294 |
Total N=866 |
|---|---|---|---|---|---|
| Sexb male (%) | 38 (88.4) | 136 (81.4) | 328 (90.6) | 256 (87.1) | 758 (87.5) |
| Age, years (SD)b | 65.9 (10.2) | 68.0 (10.9) | 70.1 (9.4) | 70.9 (9.01) | 69.8 (9.7) |
| BMI, kg/m2 | 28.0 (4.3) | 27.0 (4.2) | 28.0 (4.8) | 27.0 (4.6) | 27.5 (4.6) |
| Smoking statusb | |||||
| Ex-smoker | 29 (67.4%) | 119 (71.3%) | 287 (79.2%) | 238 (80.9%) | 673 (77.8%) |
| Smoker | 14 (32.6%) | 48 (28.7%) | 75 (20.8%) | 56 (19.1%) | 193 (22.2%) |
| Pack-years (interquartile range)a,c | 30.0 (22.5/45.0) | 36.0 (20.0/51.0) | 40.5 (28.4/60.0) | 48.0 (31.3/67.5) | 41.3 (30.0/60.0) |
| Dyspnea (MRC)c | 1.0 (0.7) | 1.2 (0.9) | 2.3 (0.9) | 3.2 (0.9) | 2.3 (1.2) |
| FEV1, % predictedc | 85.2 (5.7) | 63.7 (8.7) | 40.4 (5.9) | 25.6 (4.1) | 42.1 (17.7) |
| SaO2, %c | 92.6 (4.0) | 91.3 (7.3) | 89.6 (6.6) | 85.9 (8.8) | 89.1 (7.8) |
| No of days in hospital for any cause during previous 12 months (interquartile range)a,b | 8.0 (7.0/16.0) | 12.0 (8.0/24.0) | 12.5 (8.0/26.0) | 20.0 (10.0/37.0) | 15.0 (8.0/29.0) |
Notes: Quantitative data presented as mean (SD) unless otherwise stated.
a
Median (interquartile range)
b
Significant group differences (P<0.05)
c
Significant group differences (P<0.001).
Abbreviations: BMI, body mass index; FEV1, forced vital capacity in 1 second; GOlD, Global Initiative for Chronic Obstructive Lung Disease; MRC, Medical Research Council; SD, standard deviation.