COPD is a progressive disease

Chronic obstructive pulmonary disease (COPD) including chronic bronchitis, emphysema, or both is a progressive but treatable condition. It gets steadily worse over time.

In the early stages, a person with COPD may not be aware that anything is seriously wrong. But as their breathing slowly gets worse they cut back on the things that make them short of breath. Reducing their activity level makes their body get even more out of shape. The muscles (including the ones used for breathing) become weaker. This is called deconditioning, which contributes to their breathing problems and leads to disability.