Table 1.
Socio-demographic and clinical characteristics of 337 patients with COPD.
| n = 337* | |
|---|---|
| Males, n (%) | 314 (93.2) |
| Age (years), m (SD) | 67.9 (8.6) |
| Married, n (%) | 272 (80.7) |
| Less than primary education, n (%) | 139 (41.2) |
| Low socioeconomic status (IV-V)†, n (%) | 255 (81.5) |
| Current workers, n (%) | 55 (16.3) |
| Smoking status, n (%) | |
| Current smoker | 108 (32.8) |
| Former smoker | 219 (66.6) |
| Never smoked | 2 (0.6) |
| FEV1 post-bronchodilator (% pred.), m (SD) | 52.4 (16.2) |
| MMRC dyspnea scale, median (P25-P75) | 2 (2-3) |
| RV/TLC (%), m (SD) | 55.6 (10.1) |
| DLco (% pred.), m (SD) | 65.2 (20.8) |
| PaO2 (mmHg), m (SD) | 74.3 (10.7) |
| PaCO2 (mmHg), m (SD) | 41.8 (5.3) |
| 6MWD (m), median (P25-P75) | 440.0 (390.0-508.4) |
| BMI (Kg/m2), m (SD) | 28.2 (4.7) |
| Comorbidities: Charlson index ≥2+, n (%) | 187 (55.8) |
| Any respiratory drug treatment, n (%) | 288 (85.5) |
| Long-term oxygen therapy, n (%) | 27 (8.2) |
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in one second; MMRC, Modified Medical Research Council; RV/TLC, residual volume/total lung capacity; DLco, diffusing capacity for carbon monoxide; PaO2, partial pressure of oxygen in arterial blood; PaCO2, partial pressure of carbon dioxide in arterial blood; 6MWD, 6-minute walking distance; BMI, body mass index.
* Some variables had missing values: 24 in socioeconomic status, 8 in smoking status, 26 in RV/TLC, 46 in DLco, 11 in PaO2, 10 in PaCO2, 30 in 6MWD, 2 in Charlson comorbidities and 8 in long-term oxygen therapy.
+ One: only COPD; two or more: one or more comorbidities in addition to COPD.
†According to International Standard Classification of Occupations (ISCO).