Acupoint stimulation shows promise for heartburn

Reuters
09/12/2005
By Amy Norton

NEW YORK (Reuters Health) - A no-needle version of acupuncture could offer a new way to battle chronic heartburn, if preliminary research pans out.

The study, involving heartburn-free volunteers, found that electrical stimulation of an acupuncture point on the wrist reduced the number of "relaxations" in the band of muscle surrounding the passage from the esophagus to the stomach.

The significance of this is that temporary relaxations in the band -- called the lower esophageal sphincter (LES) -- can allow stomach acids to back up into the esophagus. These relaxations are, in fact, the "major mechanism" by which acid reflux and subsequent heartburn symptoms occur, noted the study's lead author, Dr. Richard H. Holloway of the University of Adelaide in Australia.

He and his colleagues found that among 14 healthy volunteers, acupoint stimulation reduced LES relaxations by 40 percent.

However, it's too soon to recommend acupuncture for battling heartburn, Holloway told Reuters Health.

"There is no justification at this stage for heartburn sufferers to rush out and receive acupoint stimulation treatment," he said.

The findings, the researcher stressed, are "very preliminary" and showed only that LES relaxations declined during acupoint stimulation. Whether the effect endures after the procedure -- and whether that would translate to fewer episodes of acid reflux -- requires further study, according to Holloway.

He and his colleagues report their findings in the American Journal of Physiology-Gastrointestinal and Liver Physiology.

Acupuncture has been used for more than 2,000 years in Chinese medicine to treat a wide variety of ailments. In recent years, medical studies have confirmed that the therapy may soothe chronic pain from conditions such as arthritis, as well as quell nausea and vomiting.

According to traditional medicine, acupuncture points on the skin are connected to internal pathways that conduct energy, and stimulating the points with a fine needle promotes the flow of this energy. Modern research has suggested that acupuncture may work by altering signals among nerve cells or affecting the release of various chemicals of the central nervous system.

But no one knows for sure how acupuncture works, Holloway noted, and though it has traditionally been used for stomach ailments, there had been no prior evidence that the technique affects the workings of the LES.

The volunteers in his team's study underwent electro-acupoint stimulation, which eschews needles in favor of electrodes that deliver a small electrical pulse to an acupuncture point -- in this case the Neiguan acupoint on the wrist. According to Chinese medicine, stimulation of this point aids gastrointestinal symptoms.

The researchers found that when the wrist point was stimulated, volunteers had 40 percent fewer LES relaxations -- between three and four per hour, versus six -- than they did when a "sham" point on the hip was stimulated.

Holloway and his colleagues had speculated that the reason might lie in the body's release of endorphins or other pain-killing chemicals called enkephalins. But in a second experiment, where volunteers received a medication that blocks these chemicals, acupoint stimulation still reduced LES relaxations.

"The reason why the acupoint that we chose affects (LES relaxations) is completely unclear," Holloway said.

Among the next research steps, he noted, is to show that acupoint stimulation can actually reduce acid reflux after a meal.

SOURCE: American Journal of Physiology-Gastrointestinal and Liver Physiology, August 2005.