Table. 1—

Subject characteristics

VariablesNonsmokersSmokers-GOLD 0GOLD 1–2GOLD 3–4
Subjects n18301815
Age yrs45 (37–46)46 (42–49)61 (42–72)62 (55–74)
Sex M:F8:1016:1410:89:6
Pack-yrs ex-smokers3 (32±3)7 (43±3)12 (50±7)
Pack-yrs current smokers27 (35±2)11 (48±4)3 (40±5)
FEV1 L3.4 (3.2–3.7)3.5 (3.1–3.7)2.3 (1.7–2.8)0.9 (0.7–1.7)
FEV1 % pred101 (95–108)102 (98–107)73 (63–87)34 (20–41)
FVC L4 (3.7–4.4)4.4 (3.9–4.7)3.9 (3.2–4.5)2.8 (2.5–3.2)
FVC % pred101 (96–107)106 (101–110)101 (85–120)80 (70–96)
FEV1/FVC % pred86 (82–90)80 (78–81)57 (48–66)36 (29–40)
PEF % pred101 (94–106)74 (61–88)41 (37–45)
RV % pred116 (92–140)140 (122–159)195 (155–231)
TLC % pred109 (97–121)113 (99–127)125 (110–139)
TL,CO% pred77 (60–94)65 (54–76)45 (35–56)
KCO % pred76 (66–86)75 (57–93)59 (42–70)
VA% pred105 (93–117)95 (85–106)86 (77–96)
MEF 75 % pred85 (62–108)50 (32–66)9.9 (6.8–13)
MEF 50 % pred61 (31–90)32 (20–43)7.3 (5–10)
MEF 25 % pred45 (14–73)26 (14–38)6.7 (3.6–8)
SABA67
LABA510
LABA+ICS612
Theophylline4
  • Data are presented as mean±sem, mean (95% confidence intervals) or n. GOLD: Global Initiative for Chronic Obstructive Lung Disease; M: male; F: female; FEV1: forced expiratory volume in one second; % pred: per cent predicted; FVC: forced vital capacity; PEF: peak expiratory flow; RV: residual volume; TLC: total lung capacity; TL,CO: transfer factor of the lung for carbon monoxide; KCO: carbon monoxide transfer coefficient; VA: alveolar volume; MEF 75, 50, 25: mean forced expiratory flow during the 75, 50 and 25% of the FVC; SABA: short-acting β2 agonists; LABA: long-acting β2 agonists; ICS: inhaled corticosteroids.