Diagnoses in patients without asthma
| Chronic obstructive pulmonary disease | 6 |
| Emphysema (α1‐antitrypsin deficient) | 1 |
| Cystic fibrosis | 1 |
| Cardiomyopathy | 1 |
| Obliterative bronchiolitis | 1 |
| Respiratory muscle incoordination | 1 |
| Severe anxiety and vocal cord dysfunction | 1 |