Relationship of complete respiratory dysfunction: one linked airway. A selective clinical discussion.

There is increasing clinical, immunologic, and pathophysiological consensus that allergic rhinitis (AR) and asthma are different manifestations of a single condition: inflammation of the upper and lower airways characterized by nasal and bronchial hyperresponsiveness. Most patients with asthma have AR and asthma is present in a large percentage of patients with AR. Rhinitis is a major riskfactor for asthma. Treating rhinitis in patients with AR and asthma improves not only the rhinitis but also the asthma. It is becoming clinically evident and studies have confirmed that improving the upper airway also helps the lower airway. There appears to be a connection between upper and lower airway dysfunction, suggesting one linked airway. There also seems to be a relationship between AR and asthma, suggesting that the two conditions are manifestations of one syndrome of complete respiratory dysfunction. The evidence is compelling but it is not completely established.