Effects of replacing oxitropium with tiotropium on pulmonary function in patients with COPD: a randomized study.
BACKGROUND
Inhaled bronchodilators are first line drugs in the treatment of chronic obstructive pulmonary disease (COPD). Tiotropium bromide is a recently introduced long-acting anticholinergic agent able to reduce dyspnoea and COPD exacerbations and to improve pulmonary function and quality of life. We designed a study to compare the short-term efficacy of tiotropium bromide with that of oxitropium bromide in improving pulmonary function in patients with COPD.


METHODS
Eighty patients were randomized either to continue oxitropium 800 mcg/day or to receive tiotropium 18 mcg/day. Seventy-six (39 in the tiotropium and 37 in the oxitropium group) completed the study. Plethysmography was performed at baseline and after 72 h in all patients. The changes in functional parameters in the two groups were compared by the Mann-Whitney U-test.


RESULTS
There were no differences between the two groups regarding age (72.5 vs. 74.2 years), male/female ratio (25/14 vs. 23/14) and pulmonary function at baseline. The changes in spirometric parameters were significantly greater in tiotropium- than in oxitropium-treated patients: mean forced expiratory volume in 1s (FEV(1)) increased significantly by 15% vs. 3% (P=0.017), mean FVC by 10.5% vs. 2.2% (P=0.044), and FEF 25, 50, and 75 by 34% vs. 14% (P<0.05), 33% vs. 7% (P<0.05), and 50% vs. 6% (P<0.0001), respectively; mean FRC and RV decreased nonsignificantly by 7.5% and 10% with tiotropium vs. 4.3% and 6.5% with oxitropium, respectively.


CONCLUSIONS
The replacement of oxitropium with tiotropium significantly increases pulmonary function in patients with COPD. The improvement involves also small airways that have not been investigated thus far.
Incorvaia
Cristoforo
C
Unit of Pulmonary Rehabilitation, ICP Hospital, via Bignami 1, Viale Molise 69, Milan, Italy. cristoforo.incorvaia@fastwebnet.it
Riario-Sforza
Gian Galeazzo
GG
Pravettoni
Chiara
C
Dugnani
Natale
N
Paterniti
Fulvia
F
Pessina
Laura
L
Fumagalli
Mario
M
D000368:Aged; D001993:Bronchodilator Agents / Q000627:therapeutic use; D018680:Cholinergic Antagonists / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008168:Lung / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D012129:Respiratory Function Tests / Q000379:methods; D012602:Scopolamine Derivatives / Q000627:therapeutic use*; D000069447:Tiotropium Bromide
D001993:Bronchodilator Agents; D018680:Cholinergic Antagonists; D012602:Scopolamine Derivatives; C017590:oxitropium; D000069447:Tiotropium Bromide