Study Finds Acupuncture Fights Pain
Critics question if the benefit is ‘clinically relevant’ or simply a placebo effect.
A 2012 study adds new information to a long-simmering debate: Can acupuncture relieve the chronic pain of conditions such as osteoarthritis?
The ancient medical practice of inserting fine needles into carefully selected points on the skin has gained acceptance by many physicians in the United States, yet the research on acupuncture’s pain-fighting benefits is murky. Some studies suggest that it confers superior relief when compared to common treatments such as pain relievers, while other scientific trials have found that acupuncture offers little or no benefit.
In an effort to clarify this fuzzy picture, a team of researchers led by scientist Andrew J. Vickers, PhD, attending research methodologist at Memorial Sloan-Kettering Cancer Center in New York City, conducted a meta-analysis of 29 studies on acupuncture for the treatment of neck and back pain, chronic headache, and osteoarthritis, or OA. Other teams have conducted meta-analyses of acupuncture for treating pain in the past, but Vickers’ approach was unique in an important way: Instead of lumping all study results together, he and his colleagues painstakingly assessed each individual patient’s outcome. In theory, that should give a more accurate view of how effectively acupuncture treats OA and other painful conditions. Their findings appear online in the Archives of Internal Medicine.
"This is a much superior way to do this kind of analysis," says Andrew L. Avins, MD, a clinical professor of medicine who studies pain and other health issues at the University of California, San Francisco. In an editorial that accompanies Vickers meta-analysis, Dr. Avins calls the paper "a fresh contribution to the debate" and writes, "methodologically, the authors' approach was sound."
After analyzing data for nearly 18,000 patients. Vickers and his colleagues found that people in pain who had acupuncture felt significantly better than others who weren’t treated or who only received “usual care,” such as recommendations to take pain relievers or general advice about managing symptoms. Vickers’ team also found that real acupuncture is more effective than fake, or placebo, acupuncture – but only slightly so. Researchers often study the effectiveness of therapies by comparing them to fake treatments (such as sugar pills) in order to account for the placebo effect – the phenomenon in which a patient may report feeling better simply due to his or her expectations about receiving treatment. Vickers and his colleagues found that 50 percent of acupuncture patients said their pain improved by half or more, compared to 42.5 percent of patients receiving placebo acupuncture, which may be performed several ways, such as using special telescoping needles that don’t penetrate the skin or by randomly inserting real needles.
Vickers says he believes his study confirms the value of acupuncture for treating chronic pain, even if he detected only a modest difference between real and fake needle therapy. He notes that some studies suggest that fake, also called “sham,” acupuncture may elicit an unusually strong placebo response, which could have the effect of diminishing the apparent benefits of true acupuncture when the two are compared. Also, it’s possible that sham acupuncture may actually trigger production of pain-blocking chemicals. “Just putting an acupuncture needle in the body, even if it is not at a true acupuncture point, likely has some physiologic effect,” writes Vickers in an e-mail.
Other researchers aren’t so sure. A 2010 review of 12 studies by scientists at the University of Maryland found that six months of real acupuncture produced “clinically irrelevant improvements in osteoarthritis pain” when compared to sham acupuncture. (The few studies that have examined acupuncture for rheumatoid arthritis have had generally disappointing results.) While practitioners of traditional Chinese medicine, or TCM, say that precisely placed needles heal disease by influencing the flow of energy known as chi in the body, few Western-trained physicians embrace that belief, and there remains no accepted scientific explanation for how acupuncture might work.
Questions about acupuncture’s mechanism and whether it really eases pain leave many doctors reluctant to recommend the treatment to patients. “In my opinion, it’s a placebo,” says rheumatologist Donald M. Marcus, MD, of the Baylor College of Medicine. Dr. Marcus was coauthor of a study (included in Vickers’ meta-analysis) that found no difference between acupuncture and sham acupuncture; it was published in Arthritis Care & Research in 2010. Some people may feel better after receiving acupuncture, Dr. Marcus concedes. “But it’s expensive and the effects are transient,” he says. “The relief may last a while, then you’re back to square one.”
Other doctors, including Dr. Avins, agree that acupuncture’s benefits may be due largely to the placebo effect – yet still feel it could be worth trying. Growing research suggests that placebos – whether fake needles or sugar pills – may prevent pain signals from reaching the brain and promote other biological changes that could relieve symptoms of OA and other conditions.
“If I’m suffering chronic pain and someone offers me an intervention that will improve my symptoms, I’d be thinking: Of course I want that,” says Dr. Avins. “As a patient, I just want to feel better … If our ultimate goal is to help patients achieve their goals, the mechanism is not all that relevant.”
Intriguingly, recent studies suggest that some patients may respond well to placebos even if they know they’re receiving an inert treatment, notes Dr. Avins.