[Effect of one year of treatment with inhaled beclomethasone dipropionate on airway hyperresponsiveness in stable chronic asthma].

To study the effects of an inhaled steroid on airway hyperresponsiveness (AHR) in chronic stable asthma, AHR was measured every month for 1 year in seven patients after their asthma had stabilized, i.e., when they had no wheezing or dyspnea, and their peak expiratory flow rates (PEFR) were at least 80 percent of the highest value. During the study period, no patient wheezed or had dyspnea, and daily variation in PEFR was less than 20 percent. In six patients, FEV1 was stable, and PEFR was always at least 80 percent of the highest value. AHR became less severe, by a factor of at least 2, in five of these six patients, but one patient's condition did not improve. The one patient whose PEFR fell below 80 percent of the highest value had more than a 4-fold increase in the severity of AHR. In conclusion, the severity of AHR can be reduced, even in patients with chronic stable asthma, if daily PEFR can be maintained in an optimal range by long-term use of inhaled corticosteroids.