Objectives: This study was designed to compare
the effects of a 6-month treatment with budesonide 100 μg bid (low
dose) and 400 μg bid (standard reference dose) in controlling
symptoms and lung function in a group of asthmatics with moderate
asthma (baseline FEV1 ≥ 50% and ≤ 90% of predicted
values) previously treated with inhaled beclomethasone dipropionate
(500 to 1,000 μg/d). Moreover, we investigated whether or not asthma
exacerbations could be treated by a short-term increase in the daily
dose of budesonide.
Methods: After a 2-week
run-in period and 1-month treatment with a high dose of budesonide (800μ
g bid), 213 patients with moderate asthma were assigned to
randomized treatments. Daily treatment included budesonide (bid) plus
an additional treatment in case of exacerbation (qid for 7 days).
Treatments were as follows: budesonide 400 μg plus placebo (group 1);
budesonide 100 μg plus budesonide 200 μg (group 2); and budesonide
100 μg plus placebo (group 3). Symptoms and a peak expiratory flow
(PEF) diary were recorded and lung function was measured each month. An
exacerbation was defined as a decrease in PEF > 30% below baseline
values on 2 consecutive days.
Results: We found
that that 1-month treatment with a high budesonide dose remarkably
reduced all asthma symptoms. Moreover, symptoms were under control in
all treatment groups throughout the study period. Similarly, lung
function improved and remained stable, and no relevant differences
between groups were observed. In each treatment group, the majority of
patients had no exacerbations. In patients treated with the standard
budesonide dose (group 1), the number of exacerbations and days with
exacerbations were significantly lower than in group 3
(intention-to-treat analysis). Additionally, patients treated with low
budesonide dose plus budesonide (group 2) experienced a significantly
lower number of exacerbations and days with exacerbations compared to
group 3 (per-protocol analysis).
This study demonstrates that when patients with moderate asthma had
reached a stable clinical condition with a high dose of budesonide, a
low dose of budesonide (200 μg/d) is as effective as the standard
dose (800 μg/d) in the control of symptoms and lung function over a
period of several months. Furthermore, results showed that the addition
of inhaled budesonide (800 μg/d) at onset of an asthmatic
exacerbation has a beneficial clinical effect.