[Effect of transcutaneous electrical acupoint stimulation on lung function and risks of exacerbation for patients...

To evaluate the effect of transcutaneous electrical acupoint stimulation (TEAS) on lung function, clinical symptoms, exercise tolerance and risk of acute exacerbation in patients with chronic obstructive pulmonary disease (COPD).

A total of 49 outpatients with COPD were randomly divided into TEAS group and control group by using a digital table. The clinical trials were conducted by using randomized, single-blinded and placebo-controlled method. Patients in the TEAS group were treated by TEAS of Feishu (BL13), Dingchuan (EX-B1), Zusanli (ST36) and Pishu (BL20) for 40 min, once every other day for 4 weeks, while patients in the control group were treated with placebo TEAS which the electrode plates were adhered to the same acupoints but without electrical current outputs. The treatment was conducted every 3 months in one year. In addition, patients of the two groups had no restriction on their original treatment with conventional western medicines and Chinese Materia medica. The lung function (forced expiratory volume in 1 second predicted，FEV1%, forced vital capacity predicted，FVC%) was detected using a spirometer), clinical symptom scores （CAT） for coughing, phlegm, chest tightness, climbing, family activities, out-door activities, sleeping and energy status were given. The patient's exercise tolerance was assessed using walking distance in 6 min, and the risks of acute exacerbation (times of exacerbation and hospitalization in 1 year) were recorded.

Correlative analysis showed a negative correlation between the risks of acute exacerbation and the levels of FEV1% and FVC% (P<0.01) and a positive correlation between the risks of acute exacerbation and CAT score (P<0.01). Self-comparison showed that 1 month after the treatment, the FEV1% and FVC% levels, 6MWD in the control group were significantly decreased (P<0.001, P<0.01), while the CAT score in the control group, and FEV1% and 6MWD in the TEAS group were obviously increased in comparison with their own pretreatment (P<0.05, P<0.001), but FVC% in the TEAS group and the times of exacerbation and hospitalization in the control group had no obvious changes in comparison with their own pre-treatment (P>0.05). One year (1 year) after the treatment, FEV1% and FVC% levels, 6MWD in the control group, and CAT score and times of exacerbations and hospitalization in the TEAS group were significantly decreased (P<0.001, P<0.01, P<0.05), while CAT score in the control group and 6MWD in the TEAS group were markedly increased (P<0.05, P<0.01), but FEV1% in the TEAS group and the times of exacerbation and hospitalization in the control group had no significant change compared with their own pretreatment (P>0.05). Comparison between two groups showed that after the treatment, the FEV1% (1 month) and FVC% (1 month and 1 year), 6MWD (1 month and 1 year) were significantly higher in the TEAS group than in the control group (P<0.05), while the CAT (1 month and 1 year) and times of exacerbation and hospitalization (1 year) were significantly lower in the TEAS group than in the control group (P<0.05, P<0.01, P<0.001), without significant difference in the FEV1% (1 year) level (P>0.05).

TEAS can improve the lung function, clinical symptoms, exercise tolerance, and reduce the risks of acute exacerbation in patients with COPD.