Background: Aim of this study was to evaluate the efficacy of inhaled Tiotropium bromide in COPD patients of different severities in pneumological practices during a three months clinical trial.
Methods: A randomized, double blind, placebo controlled study including COPD-patients (FEV1/FVC < 70 %, FEV1 < or = 70 % predicted; age > or = 40 years; > or = 10 pack years) of different severities was performed. The efficacy of 18 microg Tiotropium bromide once daily on lung function and exacerbations over 12 weeks was evaluated by respective pulmonary function tests (spirometry) before (trough value) and 2 hours after inhalation of study medication.
Results: 1639 patients (1236 Tiotropium bromide, 403 placebo; FEV1 reversibility after 200 microg Ipratropium bromide + 200 microg Fenoterol: 7.9 +/- 7.5 % predicted [mean +/- sd]) were randomized. After 12 weeks of treatment Tiotropium bromide led to significant increases of trough FEV1 (23 - 24 h after last inhalation; + 79 +/- 17 ml), and 2 h after Tiotropium bromide inhalation (+ 128 +/- 19 ml) (all values vs. placebo, adjusted mean +/- se, p < 0.0001). FVC and IVC were also improved significantly. In mild COPD (FEV1 > or = 50 - 70 %) improvements were most pronounced (trough FEV1 + 113 +/- 29 ml, 2 h post-inhalation + 181 +/- 33 ml; all values vs. placebo., p < 0.0001). 14.6 % of patients treated with Tiotropium bromide had a COPD exacerbation vs. 19.9 % of patients treated with placebo (p = 0.0151). The time to first exacerbation was prolonged (p = 0.0092 vs. placebo).
Conclusion: Tiotropium bromide 18 microg once daily led to a persistent improvement of lung function and a reduction of exacerbations in patients with COPD of different severities.