Effects of tiotropium on the exercise endurance of patients with stable chronic obstructive pulmonary disease

Objective To investigate the effects of tiotropium on the exercise endurance of patients with stable chronic obstructive pulmonary disease(COPD) and its possible mechanisms.Methods 60 stable COPD cases were randomly allocated into the trial group(tiotropium inhaling),as group A,and control group(placebo inhaling) as group B.Dyspneic respiration was scored on day 1,43 and 85,6 minute-walk-distance(6MWD),FEV1% and inspiratory capacity(IC) were measured respectively.Results The level of dyspneic respiration was significantly decreased in group A after receiving tiotropium 6 weeks(z=4.433,P=0.000)and 12 weeks(z=4.026,P =0.000 1).The 6MWD was significantly increased in group A after receiving tiotropium 6 weeks(t=3.004,P=0.004) or 12 weeks(t=4.594,P=0.000).The FEV1% and FEV1/FVC were improved in group A,although there was no significant difference comparing to group B(P>0.05 for all comparisons),and the improved level in FEV1% was greater than FEV1/FVC.IC was increased significantly after 6 weeks(t=3.204,P=0.002) and 12 weeks(t=3.109,P=0.003).Conclusion Tiotropium,as a new long-acting anticholinergic bronchodilator,has the function to increase IC,decrease residual capacity,and improve the exercise endurance in patients with stable COPD,thus,improve the life quality in these patients.