DISSOCIATION BETWEEN AIRWAY INFLAMMATION AND AIRWAY HYPERRESPONSIVENESS IN ALLERGIC-ASTHMA

In asthma, the acute increment of airway responsiveness caused by expo sure to allergen is associated with influx of eosinophils into the air ways. The relationship between chronic airway hyperresponsiveness and airway inflammation is unclear, as they do not change consistently fol lowing long-term antiinflammatory treatments. We studied 71 patients w ith chronic asthma and allergic sensitizization to perennial allergens . Airway responsiveness was determined by inhalation of methacholine, and airway inflammation was quantified by induced sputum (n = 28) or b ronchoalveolar lavage (n = 43) and bronchial biopsy (n = 20). The rela tionships between airway responsiveness and the numbers of different i nflammatory cells were assessed by multiple regression analysis, No si gnificant correlations were found between the degree of airway respons iveness and the numbers of inflammatory cells in sputum or bronchoalve olar lavage or bronchial biopsy. By contrast, baseline lung function w as inversely related to the numbers of eosinophils and directly relate d to the numbers of macrophages. The eosinophil cationic protein conte nts of either sputum or bronchoalveolar lavage were significantly corr elated with the percentages of eosinophils but not with airway respons iveness. We suggest that other factors (e.g., airway wall remodeling o r autonomic dysfunction) may be responsible for most of the interindiv idual variability of airway responsiveness in asthma.