Table 2.
Baseline characteristics of male smokers aged 40–65 years.a.
| Overall (n = 399) | Normal spirometry (n = 292) | GOLD I (n = 107) | |
|---|---|---|---|
| Age (years) | 50.0 (6.4) | 49.2 (6.2) | 52.3 (6.5) |
| Smoking history (years) | 31.3 (8.5) | 30.5 (8.2) | 33.5 (8.9) |
| Pack years | 24.1 (8.7) | 23.2 (8.5) | 26.6 (8.7) |
| BMI (kg/m2) | 25.4 (3.3) | 25.5 (3.4) | 25.1 (3.2) |
| Family history of obstructive lung disease | 38% | 39% | 37% |
| Parental smoking | 88% | 87% | 91% |
| Childhood smoking | 39% | 36% | 46% |
| Cough | 21% | 18% | 29% |
| ≥1 GP contact for LRT | 17% | 16% | 23% |
| FVC % predicted | 111 (13) | 109 (13) | 118 (11) |
| FEV1 % predicted | 102 (12) | 104 (12) | 97 (10) |
| FEV1/FVC ratio | 0.74 (0.06) | 0.77 (0.05) | 0.66 (0.03) |
a
Mean (SD) unless otherwise stated. GOLD I = chronic obstructive pulmonary disease stage I according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. Pack years = number of packs smoked per day times number of years smoked. BMI = body mass index. LRT = lower respiratory tract problems in the previous 12 months. FVC = forced vital capacity. FEV1 = forced expiratory volume in 1 second.