The effects of adding formoterol (F) and tiotropium (T) on exercise performance and breathlessness in patients with COPD

20 COPD patients performed spirometry and shuttle walking test (SWT) before and 180 min after the inhalation of each treatment to compare the effects of F12 µg, T 18 µg, their combination (FTC) and placebo (P) on breathlessness and SaO2 during exercise on 4 non consecutive days (7 days apart). Breathlessness was measured using a visual analog scale (VAS) at baseline and after a SWT. During and after the SWT, oxygen saturation was monitored by pulse oxymeter and we measured the lower SaO2 during exercise and the recovery time of SaO2 after exercise. All treatments, but not P, significantly (p<0.05) improved FEV1, FVC and IC over pre-dosing value; FTC was more active than F and T alone. The distance covered during the SWT increased significantly (p<0.05) with all the 3 treatments, in particular with FTC, but not with P. Breathlessness decreased significantly (p<0.05) with all the 3 treatments, but not with P, with a trend for FTC to be more effective than the single agents. The magnitude of SaO2 desaturation after the 3 treatments was similar to that observed after P (p