Acute effects of Acu-TENS on FEV₁and Blood β-endorphin Level in Chronic Obstructive Pulmonary Disease

Background • Pharmacotherapy is the mainstay of dyspnea management in patients with chronic obstructive pulmonary disease (COPD). Undesirable side effects have led to the application of alternative treatment strategies such as acupuncture. Our previous study showed that transcutaneous electrical nerve stimulation over acupuncture points (Acu-TENS), a noninvasive modality, can reduce dyspnea symptoms in patients with COPD, but the underlying mechanism is unknown. Primary Study Objective • This study investigated the effect of acu-TENS on forced expiratory volume in one second (FEV1), dyspnea, and β-endorphin levels in patients with COPD. Design • A double-blinded randomized controlled trial Setting: Hospital outpatient clinic Participants • Forty-four subjects diagnosed with COPD Intervention • Participants were randomly assigned to receive either acu-TENS or placebo-TENS on Dingchuan (EX-B1) for 45 minutes. Outcome Measures • FEV1, forced vital capacity (FVC), dyspnea visual analogue score (DVAS), respiratory rate (RR), and blood β-endorphin levels were measured before and after therapeutic intervention. Results • Our findings showed that the increase in FEV1was 24.2% greater in the acu-TENS group than the placebo group (P <.0001). The decrease in RR and DVAS was also more in the acu-TENS group by 14.2% (P <.0001) and 20.7% (P =.006), respectively. The postintervention increase in β-endorphin was significantly higher in the acu-TENS than the placebo group (18.3%) (P =.027). Furthermore, the percentage reduction in RR correlated with the increase in β-endorphin (R = -0.477, P =.033). Conclusion • An improvement in FEV1and dyspnea score at the end of Acu-TENS treatment was associated with a concurrent increase in β-endorphin level in patients with COPD.