Recurrent acute bronchitis: the association with undiagnosed bronchial asthma.

Forty-six consecutive patients with a history of recurrent acute bronchitis (chest colds) referred from primary care clinics were studied prospectively to determine if hyperreactive airways (mild bronchial asthma) was a concomitant entity. Mild bronchial asthma was diagnosed in 30/46 (65%) patients by history, physical examination, and routine spirometry, or by methacholine bronchial provocation. The incidence of mild bronchial asthma was markedly increased in patients with a history of recurrent acute bronchitis over that seen in the general population. These results emphasize a need to investigate an underlying cause in patients with recurrent acute bronchitis.