Table 1 Clinical characteristics of patients
Characteristics | Non-smokers without COPD (n = 22) | Smokers without COPD (n = 23) | Non-smokers with COPD (n = 10) | Smokers with COPD (n = 14) | \(\chi ^{2}\)/t/F | P-value |
|---|---|---|---|---|---|---|
Gender | \(\chi ^{2}\) = 1.828 | 0.609 | ||||
Male | 10 | 14 | 4 | 8 | ||
Female | 12 | 9 | 6 | 6 | ||
Age (years \(\bar{x} \pm s\)) | 55.2 ± 12.1 | 56.8 ± 15.3 | 57.1 ± 13.4 | 56.1 ± 15.3 | F = 1.745 | 0.424 |
Smoking index (package year) (\(\bar{x} \pm s\)) | – | 36 ± 14 | – | 45 ± 13 | t = 1.210 | 0.252 |
FEV1/FVC (%) | 77.3 ± 4.3 | 75.8 ± 2.2 | 65.6 ± 2.6*# | 62.9 ± 3.9*# | F = 44.745 | < 0.001 |
FEV1%pre (%) | 94.3 ± 11.5 | 93.1 ± 7.6 | 63.4 ± 7.1*# | 64.1 ± 5.8*# | F = 35.451 | < 0.001 |
PO2 (mmHg) | 80.12 ± 16.34 | 79.82 ± 17.64 | 60.31 ± 11.21*# | 58.87 ± 16.34*# | F = 38.65 | < 0.001 |
PCO2 (mmHg) | 37.34 ± 12.35 | 38.87 ± 14.15 | 41.64 ± 15.85*# | 42.59 ± 19.05*# | F = 31.87 | < 0.05 |
BMI (kg/m2) | 24.31 ± 3.30 | 24.43 ± 2.81 | 22.5 ± 2.23*# | 22.38 ± 2.41*# | F = 30.124 | < 0.05 |
Disease constitution | - | 0.270 | ||||
Lung adenocarcinoma | 12(54.5%) | 11(47.8%) | 5(50.0%) | 7(53.9%) | ||
Lung squamous cell carcinoma | 6(27.3%) | 7(30.4%) | 2(20.0%) | 2(15.4%) | ||
Lung nodules | 4(18.2%) | 5(21.8%) | 1(10.0%) | 1(7.7%) | ||
Bullous emphysema | 0(0.0%) | 0(0.0%) | 2(20.0%) | 3(23%) |