Coughing, wheezing and shortness of breath are symptoms asthma sufferers are used to. They are also the symptoms of chronic obstructive pulmonary disease (COPD). For sufferers, as well as physicians, it can be difficult to tell the difference between the two conditions.

According to a presentation at the American College of Allergy, Asthma and Immunology (ACAAI) Annual Scientific Meeting, as many as 50 percent of older adults with obstructive airway disease have overlapping characteristics of asthma and COPD. And this percentage increases as people get older.