Table 1

Characteristics of the study population

Practices of five pneumologistsGeneral practices (n=13)p Value
Asthma
n (%)
COPD
n (%)
No OAD
n (%)
Asthma
n (%)
COPD
n (%)
ACOS
n (%)
No OAD
n (%)
n154 (39.2)5 (1.3)234 (59.5)75 (46.9)25 (15.6)8 (5.0)52 (32.5)
Female91 (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]159.7 [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)24 (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)316 (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)50.047
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)60.350
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)45 (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.