Table 1.
Demographic and Clinical Characteristics of the Participants
| Healthy Control Subjects | COPD Subjects Not Receiving ICS | COPD Subjects Receiving ICS | P Value: COPD ICS vs. Health | P Value: COPD ICS vs. COPD No ICS | |
|---|---|---|---|---|---|
| N | 21 | 8 | 11 | ||
| Demographics | |||||
| Sex, M/F | 13/8 | 3/5 | 9/2 | 0.07 | 0.4 |
| Age, median (range), yr | 28 (24–35) | 66 (63–69) | 69 (65–73) | <0.0001 | 0.3 |
| Pulmonary function | |||||
| FEV1, % predicted | 108 (105–112) | 61 (55–64) | 60 (45–65) | <0.0001 | 0.4 |
| FEV1 reversibility, % | 2.9 (1.8–6.1) | 11 (4.5–19) | 10 (5–14) | 0.03 | 1 |
| FEV1/FVC ratio | 83 (79–88) | 58 (54–62) | 49 (40–59) | <0.0001 | 0.2 |
| DlCO, % predicted | ND | 74 (66–90) | 73 (55–83) | — | 0.7 |
| Va, % predicted | ND | 93 (86–96) | 85 (79–94) | — | 0.2 |
| Kco, % predicted | ND | 81 (74–94) | 82 (69–112) | — | 0.8 |
| Exhaled nitric oxide, ppb, at 50 L/s | 16 (11–21) | 31 (22–56) | 24 (13–30) | 0.2 | 0.09 |
| Clinical | |||||
| Duration of COPD | N/A | 4 (3–5) | 5 (3.5–7) | — | 0.8 |
| GOLD stage | N/A | 2 (2–2) | 2 (2–3) | — | 0.2 |
| Frequent exacerbator phenotype, ≥2/yr | N/A | 1/7 | 3/8 | — | 0.6 |
| MRC dyspnea score | 0 (0–0) | 2 (1.8–2) | 1 (1–3) | 0.001 | 0.8 |
| Atopy, skin test positive, Y/N | 0/21 | 2/6 | 5/6 | 0.002 | 0.6 |
| No. of skin test allergens positive | 0 (0–0) | 2 (1–2) | 4 (2–7) | — | 0.06 |
| Peripheral eosinophil count, 109/L | 0.1 (0.1–0.2) | 0.2 (0.1–0.2) | 0.2 (0.1–0.3) | 0.3 | 0.5 |
| Body mass index, kg/m2 | 25.3 (23.3–28.1) | 28.6 (25.7–32.2) | 28.3 (28.0–31.9) | 0.01 | 0.6 |
| Smoking status | 0/4/17 | 0/8/0 | 0/11/0 | ||
| Never smoker, n (%) | 17 (81) | 0 (—) | 0 (—) | — | — |
| Former smoker, n (% [mean pack-years]) | 4 (19 [3.5]) | 8 (100 [36]) | 11 (100 [61]) | 0.0001 | 1 |
| Current smoker, n (% [mean pack-years]) | 0 (—) | 0 (—) | 0 (—) | — | — |
| Treatment | |||||
| Inhaled steroids | No | No | Yes | — | — |
| Dose, equivalent μg BDP | N/A | N/A | 2,000 (800–2,000) | — | — |
| Maintenance oral corticosteroids, Y/N | No | No | No | — | — |
| Short-acting β-agonist, Y/N, n (%) | No | 5 (62)/3 (38) | 2 (18)/9 (82) | — | 0.07 |
| Long-acting β-agonist, Y/N, n (%) | No | 2 (25)/6 (75) | 11 (100)/0 (0) | — | 0.001 |
| Long-acting muscarinic agonist, Y/N, n (%) | No | 1 (13)/7 (87) | 7 (64)/4 (36) | — | 0.06 |
| Relevant comorbidities, n (%) | |||||
| Hypertension | 1 (5) | 1 (13) | 3 (27) | — | — |
| Cardiac disease | 0 (0) | 2 (25) | 3 (27) | — | — |
| Vascular disease | 0 (0) | 0 (0) | 3 (27) | — | — |
| Inflammatory bowel disease | 0 (0) | 1 (13) | 1 (9) | — | — |
| Other (n = 1 each) | Eczema | Hepatitis B | Spinal muscular atrophy, pernicious anemia, pleural plaques | — | — |
Definition of abbreviations: BDP = beclometasone dipropionate; COPD = chronic obstructive pulmonary disease; DlCO = diffusing capacity of the lung for carbon monoxide; GOLD = Global Initiative for Chronic Obstructive Lung Disease; ICS = inhaled corticosteroids; MRC = Medical Research Council; N/A = not applicable; ND = not determined.
Values are medians with interquartile ranges, unless stated otherwise. Percentages are of those with valid data.