The Acute Effect of Acupuncture on Endothelial Dysfunction in Patients with Hypertension: A Pilot, Randomized, Double-Blind, Placebo-Controlled Crossover Trial

Objectives: The objective of the study was to test whether acupuncture improves endothelial dysfunction in patients with hypertension and compare the effects of different acupoints to find out which one is the most suitable for the long-term follow-up study. Design: This study is a pilot, randomized, double-blind, placebo-controlled crossover trial. Subjects were randomly assigned to a sequence of four acupuncture treatment phases, each for 15 minutes with a 7-day washout period in between. Acupuncture needles were inserted at bilateral ST 36; PC 6; ST 36 plus PC 6; and placebo points. Subjects: Fifteen (15) patients with essential hypertension were the subjects. Outcome measures: Flow-mediated dilation (FMD) and blood pressure were assessed before and after acupuncture treatment. Results: FMD significantly improved with the acupuncture treatment at ST 36 (0.266 +/- 0.078 mm to 0.306 +/- 0.077 mm, p - 0.003) and ST 36 plus PC 6 (0.284 +/- 0.098 mm to 0.332 +/- 0.103 mm, p < 0.001). In contrast, FMD was unchanged after the acupuncture treatment at PC 6 or the placebo treatment. The FMD response to the acupuncture treatment at ST 36 plus PC 6 was significantly different from the response to the acupuncture treatment at PC 6 and the placebo treatment (p < 0.05, p < 0.01, respectively). The acupuncture treatment at ST 36 significantly increased FMD compared to the placebo treatment (p < 0.05). Conclusions: This study demonstrates that the acute treatment of acupuncture in hypertensive patients improves endothelial dysfunction. The beneficial effect of acupuncture could be of clinical importance to prevent the progression of cardiovascular diseases in hypertensive patients. However, the potential role of acupuncture treatment for long-term therapy has not been examined. Further studies will be necessary to demonstrate whether long-term acupuncture treatment can sustain the improvement in endothelial dysfunction.