54 The Korean Journal of Internal Medicine Vol. 25, No. 1, March 2010 Table 2. Depression and anxiety status of the study population Variables BDI Total score BDI score ≥ 16 STAI State-anxiety score Trait-anxiety score Variables BDI Total score BDI score ≥ 16 STAI State-anxiety score Trait-anxiety score Healthy control (n = 73) 13 (0 - 31) 22 (30) 40 (23 - 67) 44 (30 - 90) Healthy control (n = 73) 13 (0 - 31) 22 (30) 40 (23 - 67) 44 (30 - 90) COPD (n = 84) 17 (0 - 42)a 46 (55)a 44 (20 - 67)a 47 (20 - 66)a Chronic airway lung diseases Bronchial asthma (n = 37) 14 (2 - 36) 15 (41) 44 (23 - 67)a 45 (32 - 58) Bronchiectasis (n = 33) 16 (3 - 51)a 18 (55)a 43 (23 - 72)a 46 (28 - 64) Chronic obstructive pulmonary disease Mild to moderate (n = 48) 14 (2 - 34)a 19 (40) 44 (21 - 63) 46 (28 - 66) Severe to very severe (n = 36) 21 (0 - 42)a,b 26 (72)a,b 48 (20 - 67)a,b 50 (20 - 62)a Values are expressed as the median (range) or number (%). COPD, chronic obstructive pulmonary disease; BDI, Beck Depression Inventory; STAI, State-Trait Anxiety Inventory. a p < 0.05 compared to healthy controls. Table 3. Subgroup analysis of depression and anxiety status in patients with COPD, grouped according to GOLD staging Values are expressed as the median (range) or number (%). COPD, chronic obstructive pulmonary disease; GOLD, global initiative for chronic obstructive lung disease; BDI, Beck Depression Inventory; STAI, State-Trait Anxiety Inventory. a p < 0.05 compared to healthy controls. b p < 0.05 compared to mild to moderate COPD. mild to moderate levels of severity experienced depression, whereas 72% (26/36) of the patients with severe to very severe levels of severity experienced this condition (Table 3). The trait-anxiety scores of patients with chronic airway lung diseases did not differ significantly from those of healthy controls, with the exception of the patients with COPD, who had a median trait-anxiety score of 47 (vs. 44 for the controls, p = 0.042) and a median state-anxiety score of 44 (vs. 40 for the controls, p = 0.029). Despite their higher median trait-anxiety score, patients with COPD were not significantly more likely than healthy controls to report trait-anxiety (p = 0.054). State-anxiety was identified in 26% of the patients with COPD (vs. 16% of the controls, p = 0.176), 16% of the patients with bronchial asthma (vs. controls, p = 1.000), and 39% of the patients with bronchiectasis (vs. controls, p = 0.015) (Table 2). Overall, 79 (51%) of the 154 patients with chronic airway lung diseases exhibited clinically significant levels of depression according to their BDI scores. Thirty-four patients (22%) presented with concomitant depression and state-anxiety anxiety, and 39 (25%) presented with both depression and trait-anxiety. Determinants of depression in patients with chronic airway and lung diseases A lower BMI, history of smoking, lower predicted values of post-bronchodilator FVC and FEV1, and higher PaCO2 levels were more common among chronic airway lung disease patients with depression than among those without depression. However, no significant difference between patients with and without depression was observed with respect to age, gender, degree of hypoxia, hemoglobin level,