What is the pathophysiological mechanism behind asthma?

The pathophysiological mechanism of asthma is characterized primarily by inflammation and constriction of the airways. In asthma, the airways become hyperresponsive to various stimuli, leading to inflammation. This inflammation involves the recruitment of inflammatory cells, such as eosinophils and mast cells, which release mediators that cause bronchial smooth muscle contraction and increased vascular permeability. As a result, there is both swelling of the airway walls and an increase in mucus production.

The constriction of the airways plays a significant role, but it is not the sole factor. While excessive mucus production can occur as a secondary effect of inflammation, the overarching issue in asthma is this combination of inflammatory processes and bronchoconstriction. Moreover, infections in the lungs can trigger asthma symptoms, but they are not a primary mechanism of the disease itself. Asthma is fundamentally driven by chronic inflammation that leads to airway hyperreactivity and narrowing of the airways, hence the accuracy of identifying the mechanism as inflammation and constriction of the airways.