Characteristics of the study population
| Practices of five pneumologists | General practices (n=13) | p Value | ||||||
|---|---|---|---|---|---|---|---|---|
| Asthma n (%) | COPD n (%) | No OAD n (%) | Asthma n (%) | COPD n (%) | ACOS n (%) | No OAD n (%) | ||
| n | 154 (39.2) | 5 (1.3) | 234 (59.5) | 75 (46.9) | 25 (15.6) | 8 (5.0) | 52 (32.5) | |
| Female | 91 (59.1) | 2 (40.0) | 142 (60.7) | 44 (58.7) | 15 (60.0) | 4 (50.0) | 22 (42.3) | 0.341 |
| FENO (mean in parts per billion [SD])) | 42.4 [46.4] | 16.6 [6.8] | 22.0 [16.5] | 42.6 [47.9] | 16.2 [11.1] | 20.4 [18.6] | 24.7 [16.0] | 0.710 |
| Age (mean in years [SD]) | 40.5 [15.4] | 60.8 [17.0] | 44.6 [16.5] | 38.7 [15.1] | 55.7 [11.9] | 63.5 [10.5] | 42.8 [15.8] | 0.684 |
| FEV1 (mean of absolute values in L [SD]) | 3.32 [0.90] | 2.85 [1.72] | 3.97 [1.16] | 3.43 [0.76] | 2.12 [0.73] | 1.93 [0.55] | 3.52 [0.92] | 0.034 |
| FEV1 (mean of % of predicted [SD]) | 101.3 [17.0] | 74.1 [12.3] | 107.7 [16.3] | 100 [12.2] | 67.8 [18.5] | 68.8 [18.4] | 107.4 [12.8] | <0.001 |
| FEV1/VC (mean of % [SD]) | 81.8 [8.4] | 66.8 [9.8] | 85.6 [7.3] | 78.45 [7.02]1 | 59.7 [8.4] | 58.2 [7.6] | 82.1 [5.8] | <0.001 |
| Do you suffer from dyspnoea attacks (yes) | 33 (21.4) | 1 (20.0) | 32 (13.7) | 27 (36.0)2 | 4 (16.0) | 2 (25.0) | 13 (25.0) | <0.001 |
| Do you suffer from dyspnoea on exertion (yes) | 72 (46.8) | 4 (80.0) | 95 (40.6) | 21 (28.0)3 | 16 (64.0) | 4 (50.0) | 14 (26.9) | 0.033 |
| Have you ever suffered from wheezing in your chest? (yes) | 97 (62.9) | 5 (100.0) | 79 (33.8) | 39 (52.0) | 15 (60.0) | 3 (37.5) | 19 (36.5) | 1.000 |
| Do you often suffer from a cough? (yes) | 65 (42.2) | 3 (60.0) | 112 (47.9) | 32 (42.7) | 15 (60.0) | 4 (50.0) | 40 (76.9)5 | 0.047 |
| Do you often suffer from respiratory tract infections? (yes) | 54 (35.1) | 1 (20.0) | 79 (33.8) | 17 (22.7) | 6 (24.0) | 4 (50.0) | 29 (55.8)6 | 0.350 |
| Do you often suffer from expectoration? (yes) | 44 (28.6) | 3 (40.0) | 58 (24.8) | 19 (25.3) | 10 (40.0) | 3 (37.5) | 19 (36.5) | 0.532 |
| Have you ever woken up with a feeling of tightness in your chest? (yes) | 54 (35.1) | 1 (20.0) | 59 (25.2) | 19 (25.3) | 4 (16.0) | 3 (37.5) | 8 (15.4) | 0.070 |
| Have you ever been woken up by an attack of shortness of breath? (yes) | 35 (22.7) | 1 (20.0) | 28 (12.0) | 21 (28.0) | 3 (12.0) | 2 (25.0) | 9 (17.3) | 0.180 |
| Do you suffer from any nasal allergies? (yes) | 76 (49.4) | 0 (0) | 47 (20.1) | 40 (53.3) | 7 (28.0) | 1 (12.5) | 23 (44.2) | 0.008 |
| Do you already take medication against asthma? (yes) | 17 (11.0) | 1 (20.0) | 8 (3.4) | 19 (25.3)4 | 5 (20.0) | 0 (0) | 2 (3.8) | <0.001 |
| Do you smoke? (yes) | 19 (12.3) | 0 (0) | 20 (8.5) | 16 (21.3) | 15 (60.0) | 5 (62.5) | 13 (25.0) | <0.001 |
| Did you ever smoke? (yes) | 56 (36.4) | 4 (80.0) | 79 (33.8) | 30 (40.0) | 24 (96.0) | 8 (100) | 24 (46.2) | 0.001 |
| How much do/did you smoke? (mean in pack-year [SD]) | 10.1 [10.7] | 42.5 [3.5] | 12.9 [15.8] | 6.7 [13.3] | 35.6 [20.6] | 26.5 [17.4] | 5.0 [11.1] | <0.001 |
Values indicate the number (proportion) or mean (SD).
Subgroup differences of asthma patients from general practice versus private practice of pneumologists: 1, p<0.001; 2, p=0.002; 3, p=0.009; 4, p=0.001; Subgroup differences between patients without OAD from general practice versus private practice of pneumologists: 5, p<0.001; 6, p=0.003.
ACOS, asthma-COPD overlap syndrome; COPD, chronic obstructive pulmonary disease; FENO, fractional exhaled nitric oxide; FEV1, forced expiratory volume in 1 s; OAD, obstructive airway disease; VC, vital capacity.