Table 2. Clinical characteristics of total patients with COPD (n=744).
| Characteristics | Underweight BMI <18.5 (n=58) | Normal weight 18.5≤ BMI <25 (n=342) | Overweight 25≤ BMI <30 (n=208) | Obesity BMI ≥30 (n=136) | P value |
|---|---|---|---|---|---|
| Male, n (%) | 47 (81.0%) | 276 (80.7%) | 163 (78.4%) | 87 (64.0%) | 0.001 |
| Age, years | 68.67 [54–87] | 68.05 [45–87] | 67.12 [43–87] | 65.68 [42–88] | 0.144 |
| History of smoking | |||||
| Smoker, cases | 45 (83.3%) | 224 (70.2%) | 118 (63.4%) | 41 (36.0%) | <0.001 |
| Smoking-index | 800 [230–1,050] | 600 [0–1,000] | 400 [0–825] | 0 [0–600] | <0.001 |
| WBC | 8.19 (3.00–18.78) | 7.61 (2.24–24.10) | 8.05 (1.53–25.12) | 7.52 (1.65–16.51) | 0.208 |
| Peripheral blood neutrophils count | 4.97 (3.60–7.54) | 4.57 (3.24–6.22) | 4.69 (3.60–6.61) | 4.01 (3.14–5.72) | 0.038 |
| % peripheral blood neutrophils count | 68.97 (37.30–95.00) | 65.90 (31.00–93.50) | 66.97 (34.20–97.10) | 63.01 (37.60–92.50) | 0.008 |
| Peripheral blood eosinophil count | 0.11 (0.04–0.24) | 0.11 (0.03–0.21) | 0.09 (0.01–0.18) | 0.12 (0.05–0.23) | 0.073 |
| % peripheral blood eosinophil count | 1.60 (0.48–3.60) | 1.70 (0.50–3.20) | 1.45 (0.10–2.88) | 1.85 (0.70–3.28) | 0.099 |
| Blood EOS ≥2%, cases | 25 (43.1%) | 152 (44.4%) | 83 (39.9%) | 65 (47.8%) | 0.527 |
| CRP | 6.31 (2.13–85.21) | 4.69 (1.40–19.06) | 3.45 (1.73–11.51) | 4.00 (1.14–8.21) | 0.042 |
| BMI | 17.54 (16.96–18.14) | 22.12 (20.57–23.51) | 27.00 (25.85–28.31) | 31.25 (30.48–32.81) | – |
| Main indicators of lung function | |||||
| FEV1 | 45.65 (31.13–63.30) | 46.80 (33.30–64.00) | 52.65 (37.98–71.48) | 68.70 (55.13–78.25) | <0.001 |
| FVC | 71.55 (60.15–86.15) | 66.95 (54.20–80.00) | 66.35 (56.43–80.45) | 79.35 (66.13–87.18) | <0.001 |
| PEF | 36.40 (27.05–56.53) | 40.05 (27.65–56.33) | 49.95 (33.20–71.03) | 65.40 (50.13–79.48) | <0.001 |
| FEF25 | 18.65 (12.00–32.03) | 19.15 (11.20–34.38) | 27.90 (14.10–52.80) | 29.70 (22.70–44.05) | <0.001 |
| FEF50 | 14.50 (8.90–29.95) | 16.85 (9.90–26.28) | 20.60 (11.40–40.40) | 33.95 (22.90–46.08) | <0.001 |
| FEF75 | 24.30 (17.00–48.83) | 24.00 (15.65–39.50) | 28.40 (15.40–47.40) | 43.60 (29.30–64.10) | <0.001 |
| TLC | 77.10 (63.53–91.50) | 77.10 (64.50–87.60) | 75.10 (63.80–85.70) | 82.70 (69.75–90.40) | 0.014 |
| RV | 96.05 (75.15–130.00) | 100.60 (77.90–126.20) | 100.30 (73.70–122.10) | 104.40 (84.55–120.25) | 0.784 |
| DLCO | 36.15 (23.30–55.38) | 44.00 (30.70–62.10) | 55.70 (38.58–70.83) | 72.50 (59.38–83.80) | <0.001 |
| DLCO/VA | 44.70 (26.28–62.90) | 53.75 (37.30–78.23) | 70.15 (52.63–92.53) | 91.70 (77.60–110.50) | <0.001 |
| PAP (by Doppler cardiac ultrasound) | 34.00 (30.00–44.00) | 33.00 (28.00–41.00) | 33.00 (28.00–40.00) | 31.00 (25.00–34.00) | 0.082 |
| Times of AECOPD in 3 years | 5.50 (2.00–7.25) | 2.00 (1.00–3.00) | 2.00 (1.00–6.00) | 2.00 (1.00–5.50) | 0.038 |
| Moderate exacerbations in 3 years | 0.50 (0.00–4.00) | 0.00 (0.00–2.00) | 0.00 (0.00–3.00) | 0.00 (0.00–5.00) | 0.504 |
| Severe exacerbations in 3 years | 2.00 (1.00–5.25) | 1.00 (1.00–2.00) | 1.00 (1.00–2.00) | 1.00 (0.00–1.50) | 0.003 |
| Frequency of AECOPD per year | 1.85 (0.70–2.40) | 0.70 (0.30–1.00) | 0.70 (0.30–2.00) | 0.70 (0.30–1.85) | 0.027 |
| Length of stay of the last in-hospital | 10.00 (7.25–13.75) | 8.00 (7.00–12.00) | 8.00 (7.00–11.00) | 9.50 (8.00–12.00) | 0.177 |
| The total dosage of systemic corticosteroid | 280.00 (130.00–510.00) | 240.00 (160.00–360.00) | 200.00 (125.00–320.00) | 160.00 (90.00–420.00) | 0.143 |
Data presented as median (IQR) unless specified. COPD, chronic obstructive pulmonary disease; BMI, body mass index; WBC, white blood cell; EOS, eosinophil; CRP, C reactive protein; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; PEF, peak expiratory flow; FEF, forced expiratory flow; TLC, total lung capacity; RV, residual volume; DLCO, diffusing capacity of carbon monoxide; DLCO/VA, ratio of carbon monoxide diffusion capacity to alveolar ventilation; PAP, pulmonary arterial pressure; AECOPD, acute exacerbation of chronic obstructive pulmonary disease.