Pathophysiology of asthma.

Asthma is a complex, multifactorial disease. Although airway reactivity, inflammation, and increased mucus secretion are agreed on universally as the central components of asthma, the pathophysiology of each of these is complex. This Article reviews the physiologic events resulting in symptoms of asthma. The contributions of genetics and environment to the development of the asthma phenotype are discussed. Gastroesophageal reflux and environmental allergies are prevalent conditions in asthmatic patients and often act as significant triggers for asthma symptoms.