This study created a media storm when it was first published. Several articles in the lay press seemed to advertise it as though a true breakthrough had been made in the treatment of hypertension. I would not be surprised, if many patients consequently threw their anti-hypertensives over board and queued up at their local acupuncturist.
Good for business, no doubt – but would this be a wise decision?
The aim of this clinical trial was to examine effectiveness of electroacupuncture (EA) for reducing systolic blood pressure (SBP) and diastolic blood pressures (DBP) in hypertensive patients. Sixty-five hypertensive patients not receiving medication were assigned randomly to one of two acupuncture intervention. Patients were assessed with 24-hour ambulatory blood pressure monitoring. They were treated by 4 acupuncturists with 30-minutes of EA at PC 5-6+ST 36-37 or LI 6-7+GB 37-39 (control group) once weekly for 8 weeks. Primary outcomes measuring effectiveness of EA were peak and average SBP and DBP. Secondary outcomes examined underlying mechanisms of acupuncture with plasma norepinephrine, renin, and aldosterone before and after 8 weeks of treatment. Outcomes were obtained by blinded evaluators.
After 8 weeks, 33 patients treated with EA at PC 5-6+ST 36-37 had decreased peak and average SBP and DBP, compared with 32 patients treated with EA at LI 6-7+GB 37-39 control acupoints. Changes in blood pressures significantly differed between the two patient groups. In 14 patients, a long-lasting blood pressure–lowering acupuncture effect was observed for an additional 4 weeks of EA at PC 5-6+ST 36-37. After treatment, the plasma concentration of norepinephrine, which was initially elevated, was decreased by 41%; likewise, renin was decreased by 67% and aldosterone by 22%.
The authors concluded that EA at select acupoints reduces blood pressure. Sympathetic and renin-aldosterone systems were likely related to the long-lasting EA actions.
These results are baffling, to say the least; and they contradict a recent meta-analysis which did not find that acupuncture without antihypertensive medications significantly improves blood pressure in those hypertensive patients.
So, who is right and who is wrong here?
Or shall we just look for alternative explanations of the effects observed in the new study?
There could be dozens of reasons for these findings that are unrelated to the alleged effects of acupuncture. For instance, they could be due to life-style changes suggested to the experimental but not the control group, or they might be caused by some other undisclosed bias or confounding. At the very minimum, we should insist on an independent replication of this trial.
It would be silly, I think, to trust these results and now recommend acupuncture to the millions of hypertensive patients worldwide, particularly as dozens of safe, cheap and very effective treatments for hypertension do already exist.