05 December 2019
Pharmacological therapy and pulmonary rehabilitation are useful for exertional dyspnoea in patients with chronic obstructive pulmonary disease (COPD); however, several patients have no meaningful improvements. Although acupuncture significantly improves exercise intolerance and dyspnoea, the pathophysiological mechanism of these effects is unknown; therefore, we evaluated this mechanism using cardiopulmonary exercise testing in a single-arm, open experimental study.
Sixteen patients with COPD underwent acupuncture once a week for 12 weeks. Primary outcomes were exercise performance parameters, including peak oxygen uptake in the incremental exercise tests (IETs) and the time to the limit of tolerance measured in constant work rate exercise tests (CWRETs) at 70% peak work-rate of the IET. IETs and CWRETs were performed at baseline and at weeks 12, 16, and 24.
During the time course, there were significant increases in peak oxygen uptake (p = 0.018) and minute ventilation (V̇ E, p = 0.04) in the IETs. At 12 weeks, the endurance time significantly increased (810 ± 470 vs 1125 ± 657 s, p < 0.001) and oxygen uptakes at terminated exercise were significantly lower (771 ± 149 mL/min, p < 0.05) than those at baseline (822 ± 176 mL/min) in CWRETs. The significant decreases in oxygen uptake and minute ventilation and improvements in Borg scale scores were also observed during CWRETs after acupuncture. The decreases at isotime in the Borg scale (r = −0.789, p = 0.0007) and V̇ E (r = −0.6736, p = 0.0042) were significantly correlated with the improvement of endurance time.