Asthma and COPD can sometimes be confused for one another. Many people with asthma have similar breathing problems like those with COPD, making diagnosis of COPD a little challenging. However, asthma and COPD are quite different from one another:

-Asthma has a very early onset, whereas COPD sets in mostly at 40+ years.
-Smoking is not a causal factor for asthma as it is for COPD.
-Asthma does not have symptoms of increased sputum (mucus) production like with COPD.
-Asthma remains mostly stable throughout your life, with variable symptoms. COPD worsens with recurring symptoms.