Asthma can be mistaken for other breathing issues

Researchers ruled out asthma in 203 people, most of whom were taking asthma medicine.

Many adults who believe they have asthma actually may not. Using random dialling, Canadian researchers recruited 613 men and women who had been given a diagnosis of asthma within the past five years. Then over four visits they gave them a series of drug challenges and spirometry, a physical test of breathing capacity, to confirm or rule out the disorder.
 
The researchers were able to rule out asthma in 203, or about a third of subjects, most of whom were taking asthma medicine. They tapered their medicine, and 181 of them showed no signs of asthma over a 15-month