THE EFFECTS OF INHALED BECLOMETHASONE DIPROPIONATE ON LUNG-FUNCTION AND HISTAMINE RESPONSIVENESS IN RECURRENTLY WHEEZY INFANTS

Inhaled steroids improve pulmonary function and bronchial responsivene ss in older asthmatics. Data from studies using subjective outcome mea sures to determine the effectiveness of inhaled steroids in infants wi th recurrent wheezing are equivocal. Therefore, this study tested the hypothesis that beclomethasone dipropionate improves pulmonary functio n, including bronchial responsiveness to histamine, in recurrently whe ezy infants The study was double blind, placebo controlled lasting nin e weeks. After the first baseline week, pulmonary function was measure d using the rapid thoraco-abdominal compression technique and bronchia l responsiveness assessed with a histamine challenge test. Infants wer e then randomly allocated to receive doses of placebo or beclomethason e dipropionate (100 mu g/puff) from metered aerosols. Two puffs of tes t aerosol were administered twice daily for eight weeks via a large vo lume spacer fitted with a facemask. Symptoms were recorded daily and p ulmonary function and bronchial responsiveness assessed at the end of the treatment period; 50 infants, median age 12 months (range 5 to 18 months), were recruited. Twenty three in the beclomethasone dipropiona te group and 15 in the placebo group completed the study and had pairs of pulmonary function measurements. Three were probable treatment fai lures (one beclomethasone dipropionate, two placebo), three were possi ble treatment failures (placebo), and others were non-compliant with s tudy protocol. Baseline variables were not significantly different bet ween those infants who completed the study and those who did not. Becl omethasone dipropionate and placebo groups were similar in all respect s at baseline. Lung function and improved for both groups during the s tudy. Bronchial responsiveness increased significantly in the placebo group but there were no statistically significant differences between groups for any of the other outcome measures. It is concluded that bec lomethasone dipropionate (400 mu g daily) via a large volume spacer do es not significantly improve lung function or symptoms in recurrently wheezy infants symptoms of infants but might have a beneficial effect on bronchial responsiveness.