Pathophysiology of Asthma
Ajith Kumar, Tisekar Owais Rafique Ahmed
Abstract
Asthma is a complex heterogeneous disorder characterized by reversible airflow limitation and airway inflammation. The inflammatory response not only leads to flow limitation and smooth muscle contraction but also airway remodelling. Airway remodelling contributes to irreversible airflow limitation and functional limitation. Pathophysiology of asthma can be approached as genotypic as well as phenotypic variants causing variable inflammatory response. About 50–70% of the asthmatics exhibit genetic predisposition in a complex non-Mendelian pattern. Part of the genetic risk for asthma is thought to result from genotype-specific responses to environmental factors during infancy and childhood. Various cytokines and chemical mediators are involved in the inflammatory process leading to bronchial narrowing and later bronchial remodelling. Identifying the pathophysiology of asthma is important in planning treatment targeted against various components of inflammation.