Demographics of the patients within the 3 diagnostic groups
Parameters
Asthma
ACO
COPD
All
Measurements (% total)
198 (28.8)
152 (22.1)
338 (49.1)
688 (100)
Gender (male/female, n)
89/109
83/69
186/152
358/330
Age (mean, years)
50.9 ± 18.1
63.1 ± 13.4
67.9 ± 8.6
61.9 ± 14.9
BMI (mean, kg/m2)
27.1 ± 5.6
27.0 ± 5.4
26.6 ± 6.7
26.8 ± 6.1
Spirometry
FEV1z-score ± SD
–1.3 ± 1.3
–2.1 ± 1.5
–3.3 ± 1.4
–2.5 ± 1.6
FEV1 % predicted ± SD
92.3 ± 12.50
85.6 ± 18.65
54.9 ± 16.10
79.2 ± 22.45
FEF25–75z-score ± SD
–1.1 ± 1.2
–1.4 ± 1.0
–1.9 ± 0.7
–1.5 ± 0.9
End-expiratory level
FRCplethz-score ± SD
0.65 ± 1.29
1.73 ± 1.60
2.56 ± 2.06
1.83 ± 1.95
Airway dynamics
sReffz-score ± SD
6.43 ± 5.17
9.38 ± 5.54
14.23 ± 6.52
10.91 ± 6.86
sWOB z-score ± SD
4.98 ± 5.69
8.23 ± 6.09
12.61 ± 7.06
9.45 ± 7.27
Gas exchange
DLCO z-score ± SD
–0.6 ± 0.9
–1.5 ± 1.1
–2.25 ± 1.2
–1.6 ± 1.3
SD: standard deviation
Declarations
Acknowledgments
The authors are grateful to the staff of all study centers, especially to the study nurses for their excellent and enduring work in data collection, and the authors thank Prof. Sabina Gallati from Human Genetics of Hirslanden Precise, Zürich, for the critical reviews of the manuscript.
Author contributions
RK: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. HM: Writing—review & editing. Both authors read and approved the submitted version.
Conflicts of interest
The authors declare that they have no conflicts of interest.
Ethical approval
The study was planned according to the Federal Law of Human Research, conceptualized according to the Swiss Ethics Committees on research involving humans, and was conducted in accordance with the tenets of the Declaration of Helsinki. The study is part of the framework of the project entitled “Functional diversification of the Asthma-ACO-COPD multi-center study” (ID 2017-00259), approved by the Governmental Ethics Committees of the State of Bern, St. Gallen, Solothurn, and Zürich (project KEK-BE PB_2017-00104).
Consent to participate
All 4 Ethics Committees exempted the informed consent to participate since the data were retrospectively evaluated and anonymous.
Consent to publication
Not applicable.
Availability of data and materials
Master-files have been stored and secured in the Clinical Trial Unit (CTU), Hirslanden, Corporate Office, CH-8152 Glattpark, Switzerland, and are available upon request from the corresponding author (richard.kraemer@hirslanden.ch) or the office manager, Mr. Daniel Tschopp, Head Clinical Trial Unit, Hirslanden (ClinicalTrialUnit.Hirslanden@hirslanden.ch).
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