Acupuncture (5) -effectiveness
Effectiveness
Professor of Complementary and Alternative Medicine Edzard Ernst and his colleagues have produced regular systematic reviews of the acupuncture literature. In 2007, they concluded that "the emerging clinical evidence seems to imply that acupuncture is effective for some but not all conditions." Several review articles discussing the effectiveness of acupuncture have concluded that its effects may be due to placebo. Evidence for the treatment of psychological conditions other than pain is equivocal. Acupuncture's greatest effectiveness appears to be in symptomatic control of pain and nausea.
The World Health Organization and the United States' National Institutes of Health (NIH) have stated that acupuncture can be effective in the treatment of neurological conditions and pain, though these statements have been criticized for bias and a reliance on studies that used poor methodology. Reports from the USA's National Center for Complementary and Alternative Medicine (NCCAM), the American Medical Association (AMA) and various USA government reports have studied and commented on the efficacy of acupuncture. There is general agreement that acupuncture is safe when administered by well-trained practitioners using sterile needles, but not on its efficacy as a medical procedure.
Effectiveness research
Research on acupuncture is fraught with difficulties for a variety of reasons. Due to acupuncture's invasive nature, one of the major challenges in efficacy research is in the design of an appropriate placebo control group.
The most commonly proposed placebo control has been "sham acupuncture" to control for different aspects of traditional acupuncture. This includes needling sites not traditionally indicated for treatment of a specific condition to control for the effectiveness of traditional acupuncture for specific conditions and/or needling performed superficially or using retracting needles or non-needles (including toothpicks) to control for needle penetration and stimulation.
A 2012 meta-analysis found significant differences between true and sham acupuncture, which indicates that acupuncture is more than a placebo when treating chronic pain (even though the differences were modest and non-specific effects were still considered an important part of the therapeutic effect).
A 2009 review, however, concluded that the specific points chosen to needle does not matter, and no difference was found between needling according to "true" points chosen by traditional acupuncture theory and "sham" acupuncture points unrelated to any theory. The authors suggested four possible explanations for their observed superiority of both "true" and sham acupuncture over conventional treatment, but lack of difference in efficacy between "true" and sham acupuncture:
- The complexity and characteristics of acupuncture, sham or real, might maximize placebo effects;
- The effects of acupuncture are not specific and needling any point affects the whole body (the first two findings suggesting that point specificity may not matter or the effects of needling specific points are overwhelmed by the nonspecific effects of acupuncture);
- The blinding between "true" and "sham" acupuncture might be accurate but can never be adequate when compared to drug treatments, resulting in more patients in the conventional care groups dropping out of the trials or reporting more negative outcomes; and
- Specific to "true" and "sham" acupuncture only, the skill level of practitioners might be more relevant regarding true acupuncture as the sham procedures tend to be inflexible.
Edzard Ernst and Simon Singh stated in 2008 that (as the quality of experimental tests of acupuncture have increased over the course of several decades through better blinding, the use of sham needling as a form of placebo control, etc.) the "more that researchers eliminate bias from their trials, the greater the tendency for results to indicate that acupuncture is little more than a placebo." In line with this, a 2006 study of clinical trials involving sham and no-treatment control groups found that more recent studies showed no change in treatment effects but an increase in placebo effects. Also, when "placebo needles" (in which the needle retracts into a handle rather than penetrating the skin) were introduced to the study of acupuncture, the majority of studies conducted using these needles concluded the effects of acupuncture were due to placebo.
Other authors have suggested randomized controlled trials may under-report the effectiveness of acupuncture as the "sham" treatment may still have active effects, though this position undercuts the traditional theory of acupuncture which associates specific acupuncture points with specific and distinct results.
It has also been stated that positive results from some studies on the efficacy of acupuncture may be as a result of poorly designed studies or publication bias. The possiblity of a strong publication bias, especially in certain countries, also casts doubt on the effectiveness of acupuncture. A review of studies on acupuncture found that trials originating in China, Japan, Hong Kong and Taiwan were uniformly favourable to acupuncture, as were ten out of 11 studies conducted in Russia. A 2011 assessment of the quality of randomized controlled trials on TCM, including acupuncture, concluded that the methodological quality of most such trials (including randomization, experimental control and blinding) was generally poor, particularly for trials published in Chinese journals (though the quality of acupuncture trials was better than the drug-related trials). The study also found that trials published in non-Chinese journals tended to be of higher quality.
Pain
A 2012 meta-analysis concluded that acupuncture is effective for the treatment of chronic pain. A 2011 review of eight high-quality Cochrane reviews found that acupuncture is effective in the treatment of migraines, neck disorders, tension-type headaches, and peripheral joint osteoarthritis. Another 2011 review concluded that there was unanimously positive research supporting acupuncture for neck pain, but that little truly convincing evidence existed for other types of pain." A 2009 Cochrane Review of the use of acupuncture for migraine treatment concluded that "true" acupuncture wasn't more efficient than sham acupuncture, however, both "true" and sham acupuncture appear to be more effective than routine care in the treatment of migraines, with fewer adverse effects than prophylactic drug treatment.
There is conflicting evidence that acupuncture may be useful for osteoarthritis of the knee, with both positive and negative results. The Osteoarthritis Research Society International released a set of consensus recommendations in 2008 that concluded acupuncture may be useful for treating the symptoms of osteoarthritis of the knee. Results for osteoarthritis in other joints suggest insignificant effects in short-term pain relief, which may be due to placebo or expectation effects.
For acute low back pain, there is insufficient evidence to recommend for or against either acupuncture or dry needling. For chronic low back pain, however, "there is evidence of pain relief and functional improvement for acupuncture, compared to no treatment or sham therapy. These effects were only observed immediately after the end of the sessions and at short-term follow-up." The same review finds acupuncture to be more effective than other CAM treatments, but no more effective than conventional therapy. Still, the combination of acupuncture and convential therapy was slightly better than conventional therapy alone. A review for the American Pain Society/American College of Physicians found fair evidence that acupuncture is effective for chronic low back pain. Conducting research on low back pain is unusually problematic since most patients have experienced "conventional care" 鈥?which is itself relatively ineffective鈥?and have low expectations for it. As such, conventional care groups may not be an adequate scientific control and may lead to nocebo effects that can inflate the apparent effectiveness of acupuncture.
Reviews have found inconclusive evidence regarding acupuncture efficacy in treating shoulder pain and lateral elbow pain.
A 2009 review of the highest quality clinical trials of acupuncture in the treatment of pain (in general), published in the British Medical Journal, reported a "small analgesic effect of acupuncture was found, which seems to lack clinical relevance and cannot be clearly distinguished from bias. Whether needling at acupuncture points, or at any site, reduces pain independently of the psychological impact of the treatment ritual is unclear."
Medical acupuncturist Steven E. Braverman, who separates the "needling" of acupuncture from its theoretical basis within traditional Chinese medicine, stated in 2004 that he believed needling has been successful in treating some pain and recommended acupuncture be considered a complementary therapy for various conditions. Braverman and other medical acupuncturists also stated that definitive conclusions based on research findings were rare because the state of acupuncture research was poor, but that it was improving.
Controversy remains over whether, and under what conditions, sham acupuncture may function as a true placebo in studies on pain, in which insertion of needles anywhere near painful regions may elicit a beneficial response. A 2007 review article noted that superficial needling, the primary form of traditional acupuncture in Japan, can stimulate endogenous production of opioids resulting in non-specific analgesia.
Nausea and vomiting
Stimulation of a particular acupuncture point (P6, located on the underside of the forearm, several finger-widths from the wrist) is traditionally thought to relieve nausea. A 2004 Cochrane Review initially concluded that acupuncture appeared to be more effective than antiemetic drugs in treating postoperative nausea and vomiting, but the authors subsequently retracted this conclusion due to a publication bias in Asian countries that had skewed their results. An updated Cochrane Review published in 2009 concluded that both penetrative and non-penetrative stimulation of the P6 acupuncture point was approximately equal to, but not better than, preventive antiemetic drugs for postoperative nausea and vomiting though only 10% of the studies had adequate information on patient blinding regarding receiving standard or nonstandard acupuncture. A 2011 Cochrane Review on the treatment of vomiting after the start of chemotherapy concluded that acupuncture point stimulation with needles and electroacupuncture reduced the number of times subjects vomited on the day of treatment, but were no help regarding immediate or delayed nausea. Acupressure was found to reduce the short-term severity of nausea, but was no help over the long term and did not influence vomiting. All of the experiments reviewed also used medication to control vomiting, though trials involving electroacupuncture did not use the newest drugs available.
A 2008 review examined randomized controlled trials on the effects of the P6 point, as well as points thought to rely on the same meridian, at preventing PONV within the first 24 hours of surgery. Three of the ten studies found statistically significant evidence that acupuncture could prevent PONV though comparison of the studies is difficult due to the use of varied methodologies (different patient groups, different ways of stimulating the P6 point such as a needle versus finger pressure versus a special bracelet, timing and length of application of pressure, the use of one versus both arms, whether a general anaesthetic was used, and the mixture of men and women in the studies). The reviewer ultimately concluded that "due to the lack of robust studies, [this review] found that neither acupressure nor acupuncture was effective in preventing or managing PONV in adults" and suggested further research to clarify issues such as the length and type of stimulation applied, training of those applying stimulation and gathering data, risk factors for PONV, inclusion of proper placebos, and the analysis of specific population. The author also suggested disagreement with previous systemic reviews were due to their inclusion of older studies with poorer methodologies, while the more recent, better quality studies included in the review offered more negative results.
Fertility and childbirth
Proponents believe acupuncture can assist with fertility, pregnancy and childbirth, attributing various conditions of health and difficulty with the flow of qi through various meridians.
A 2008 Cochrane review of randomized controlled trials of in vitro fertilisation and acupuncture suggests that acupuncture performed on the day the embryo is transferred to the uterus may increase the live birth rate, although this effect could be due to the placebo effect and the small number of women included in acceptable trials. There was no evidence of benefit when the egg was initially removed and the review did not recommend the routine use of acupuncture during the luteal phase until better trials were available. A different review article published in 2010 found that there was no evidence acupuncture improved pregnancy rates irrespective of when it was performed and recommended against its use during in vitro fertilization either during egg retrieval or implantation.
Lack of evidence for other conditions
The Danish Knowledge and Research Center for Alternative Medicines has a fully updated list of all the Cochrane Collaboration regarding acupuncture and the overall conclusion is:
...the majority of the Cochrane reviews about acupuncture, acupressure, electroacupuncture and moxibustion [concluded] there exists no solid evidence to determine the effectiveness of the treatments. The reviews point out that many of the studies suffer from methodological defects and shortcomings. Furthermore, the number of trial subjects has been limited. Thus most of the overall conclusions are uncertain.
For the following conditions, the Cochrane Collaboration or other review articles have concluded there is insufficient evidence to determine whether acupuncture is beneficial, often because of the paucity and poor quality of the research, and that further research is needed:
There is mixed evidence for attention deficit hyperactivity disorder, with one review article concluding there was no evidence to support the use of acupuncture and another concluding there was limited evidence but cautioned that firm conclusions could not be drawn because of the risk of bias.
The World Health Organization has a list of diseases treatable with acupuncture.
