[Evaluation of the bronchial tonus, basal and following bronchodilators, in subjects with allergic rhinitis].

Data emerging from forced, basal and postbronchodilator expirograms in asymptomatic allergic rhinitis patients have been compared with those from a group of normal controls. Basal averages and average percentage variations after the bronchodilator show that MEF 75, FEF 25-75 and, to a lesser extent, FEV1 are able to differentiate atopic rhinitis patients from the normal. Comparison between percentages in patients arbitrarily considered bronchodilator positive in the two groups reveals significant differences in MEF 75 and FEF 25-75 but not in FVC and FEV1. Atopic rhinitis patients feature increased basal bronchial tone largely maintained by latent bronchospasm. Measurement of forced, basal and postbronchodilator flows can supply useful indications for the study of allergic rhinitis patients.