SOURCES: John Longhurst, M.D., Ph.D., cardiologist, University of California, Irvine; Randall Zusman, M.D., director, division of hypertension, Massachusetts General Hospital Heart Center, and associate professor, medicine, Harvard Medical School, Boston; Aug. 19, 2015, Medical Acupuncture
WEDNESDAY, Sept. 2, 2015 (HealthDay News) -- Can acupuncture benefit people with mildly or moderately elevated blood pressure?
Perhaps, a small study suggests, but the researchers behind the trial acknowledge that it's too soon to say for sure.
The researchers found that blood pressure levels declined slightly in a small group of patients treated 30 minutes a week with "electroacupuncture" -- where the needles carry low-level electrical stimulation -- at specific points of the body.
"Potentially, blood pressure can be kept low with a monthly follow-up treatment," said study co-author Dr. John Longhurst, a cardiologist at the University of California, Irvine.
An estimated 70 million U.S. adults -- one in three -- have high blood pressure, according to the U.S. Centers for Disease Control and Prevention. It's believed that only half have their condition under control. High blood pressure can lead to stroke and heart disease.
Blood pressure can often be lowered by becoming more fit, taking medications or both. But these approaches don't work for everyone, and medication can cause side effects, especially among the elderly.
Acupuncture, an ancient Chinese therapy, is increasingly viewed as a possible alternative, the researchers said in background notes with the study. Practitioners insert thin needles into key points on the body in an attempt to rebalance the flow of energy.
Because previous studies on acupuncture's effect on high blood pressure have had mixed results, the researchers set out to explore the subject more thoroughly. They compared electroacupuncture at two sets of points in their study of 65 high blood pressure patients.
High blood pressure was defined as 140-180 mm Hg over 90-99 mm Hg. None of the participants was taking blood pressure medication.
Normal blood pressure is defined as 119/79 or lower, according to the U.S. Institutes of Health.
Patients were randomly assigned to one of two types of acupuncture for eight weeks. One type targeted the inner wrists and legs below the knee -- points shown to potentially lower blood pressure in previous research. The other technique involved the forearm and lower leg and resulted in no blood pressure improvement, the researchers said.
"A noticeable drop in blood pressure was observed in 70 percent of the patients treated at the effective points, an average of 6 to 8 mm Hg for systolic blood pressure [the top number] and 4 mm Hg for diastolic blood pressure [the lower number]," Longhurst said.
These changes were considered slow and long-lasting -- persisting for about six weeks, the study found.
The researchers also found that blood pressure readings dipped further in a group of "high responders" that underwent monthly treatment for six more months.
Exactly how acupuncture might improve blood pressure isn't clear. Longhurst said it's possible that stimulation of the affected nerves stimulates areas of the brain that control blood pressure.
In some cases, he said, insurance might cover the alternative treatment, which can cost $60 to $120 per visit.
Longhurst acknowledged that the research doesn't address whether acupuncture could help patients already taking blood pressure medication.
Dr. Randall Zusman, director of the division of hypertension at Massachusetts General Hospital Heart Center, said the study leaves several questions unanswered.
Zusman said the study doesn't include enough information about the participants and their blood pressure history. It's not clear, for example, how recently they took medication, if they did. And he thought the variation in blood pressure among participants was too great. A smaller range would have provided more useful results, said Zusman, who has studied acupuncture.
Still, "the outcomes are interesting and exciting," he said, "and I'm encouraged that it might have been effective."
So what should you do if you have high blood pressure?
Zusman said consider modifying your lifestyle, using medication and trying strategies such as relaxation training. Acupuncture is a low-risk procedure, and it could be useful, too, he said.
Longhurst said further studies on acupuncture's potential for high blood pressure are warranted. But, no additional research is planned, he said, because it's difficult to find funding.
The study was published recently in the journal Medical Acupuncture.
For more about blood pressure, visit the U.S. National Heart, Lung, and Blood Institute.