A 4-year trial of tiotropium in chronic obstructive pulmonary disease.

Background Previous studies showing that tiotropium improves multiple end points in patients with chronic obstructive pulmonary disease (COPD) led us to examine the long-term effects of tiotropium therapy. Methods In this randomized, double-blind trial, we compared 4 years of therapy with either tiotropium or placebo in patients with COPD who were permitted to use all respiratory medications except inhaled anticholinergic drugs. The patients were at least 40 years of age, with a forced expiratory volume in 1 second (FEV1) of 70per cent or less after bronchodilation and a ratio of FEV1 to forced vital capacity (FVC) of 70per cent or less. Coprimary end points were the rate of decline in the mean FEV1 before and after bronchodilation beginning on day 30. Secondary end points included measures of FVC, changes in response on St. George's Respiratory Questionnaire (SGRQ), exacerbations of COPD, and mortality. Results Of a total of 5993 patients (mean age, 65±8 years) with a mean FEV1 of 1.32±0.44 liters after bronchodilation (48% of predicted value), we randomly assigned 2987 to the tiotropium group and 3006 to the placebo group. Mean absolute improvements in FEV1 in the tiotropium group were maintained throughout the trial (ranging from 87 to 103 ml before bronchodilation and from 47 to 65 ml after bronchodilation), as compared with the placebo group (P<;0.001). After day 30, the differences between the two groups in the rate of decline in the mean FEV1 before and after bronchodilation were not significant. The mean absolute total score on the SGRQ was improved (lower) in the tiotropium group, as compared with the placebo group, at each time point throughout the 4-year period (ranging from 2.3 to 3.3 units, <P0.001). At 4 years and 30 days, tiotropium was associated with a reduction in the risks of exacerbations, related hospitalizations, and respiratory failure. Conclusions In patients with COPD, therapy with tiotropium was associated with improvements in lung function, quality of life, and exacerbations during a 4-year period but did not significantly reduce the rate of decline in FEV1