Bronchial responsiveness to methacholine: relation to respiratory symptoms and pulmonary function.

A methacholine bronchial provocation test was administered to 290 subjects obtained from the 1,900 male volunteers participating in the Normative Aging Study. A positive response (less than 20% decline in FEV1) was obtained in 83 subjects. A positive response was associated with current smoking, presence of wheeze and reduced FEV1. Bronchial responsiveness, cigarette smoking, normal subjects, FEV1.