Correlation of methacholine-induced non-specific bronchial reactivity and cold air hyperventilation challenge.

The degree of bronchoconstriction seen with cold air hyperventilation challenge was determined in 48 adult subjects with known degrees of methacholine-induced bronchial reactivity. The degree of bronchial reactivity as determined by the cold air hyperventilation challenge significantly correlated with the non-specific bronchial reactivity determined by a methacholine inhalation challenge. Cold air hyperventilation challenge can accurately confirm the presence of reactive airway disease.