Effect of repeated Waon therapy on exercise tolerance and pulmonary function in patients with chronic obstructive pulmonary disease: a pilot controlled clinical trial

Purpose: Controlled clinical trials evaluating the efficacy of repeated Waon therapy for patients with chronic obstructive pulmonary disease (COPD) have yet to be conducted. The purpose of the present study was to evaluate whether repeated Waon therapy exhibits an adjuvant effect on conventional therapy for COPD patients.

Patients and methods: This prospective trial comprised 20 consecutive COPD patients who satisfied the criteria of the Global initiative for chronic Obstructive Lung Disease (GOLD) guidelines, stages 1-4. They were assigned to either a Waon or control group. The patients in the Waon group received both repeated Waon therapy and conventional therapy, including medications, such as long-acting inhaled β2 agonists, long-acting anticholinergics and xanthine derivatives, and pulmonary rehabilitation. The Waon therapy consisted of sitting in a 60°C sauna room for 15 minutes, followed by 30 minutes of being warmed with blankets once a day, 5 days a week, for a total of 20 times. The patients in the control group received only conventional therapy. Pulmonary function and the 6-minute walk test were assessed before and at 4 weeks after the program.

Results: The change in vital capacity (0.30 ± 0.4 L) and in peak expiratory flow (0.48 ± 0.79 L/s) in the Waon group was larger than the change in the vital capacity (0.02 ± 0.21 L) (P=0.077) and peak expiratory flow (-0.11 ± 0.72 L/s) (P=0.095) in the control group. The change in forced expiratory flow after 50% of expired forced vital capacity in the Waon group, 0.08 (0.01-0.212 L/s), was larger than that in the control group, -0.01 (-0.075-0.04 L/s) (P=0.019). Significant differences were not observed in the change in any parameters in the 6-minute walk test. Data are presented as means ± standard deviation or median (25th-75th percentile).

Conclusion: The addition of repeated Waon therapy to conventional therapy for COPD patients can possibly improve airway obstruction.