Discussion
It is no longer appropriate to consider mucus
hypersecretion as an “innocent accompaniment of
COPD”.12,13 Recent investigators have observed a
significant association between airway hypersecretion
and all causes of mortality, and between illness and death
among individuals with COPD in particular.14,15,16,17 In
COPD patients with significant chronic bronchitis,
pathogenic sequence of bronchial inflammation—
characterized by neutrophil infiltration —results in
increased protease activity