Is acupuncture effective ? January 23, 2009Posted by dorigo in news, science.
Tags: acupuncture, alternative medicine, cochrane collaboration, pseudoscience
I have always been highly sceptical on the utility of acupuncture, as much as on any other “alternative medicine” techniques. Man has practiced the most diverse healing techniques since thousands of years ago, and the lack of knowledge of the placebo effect has hampered the effectiveness of the “trial and error” approach, which on general grounds should be expected to slowly evolve and end up producing good results, given enough time. Some empirical techniques have survived to this day, and the onset of a scientific approach to medicine has not marginalized them as much as one would think reasonable.
To be fair, acupuncture should not be placed at the same level of deception as homeopathy, which is really just placebo dressed up with a pseudo-scientific dusting, with the aggravating condition that it is a parasitic technique of modern medicine, being based on active molecules known to be beneficial for the pathology they try to cure.
While homeopathy is based on the irrational and totally groundless belief that water remembers molecular structures it has come in contact with, acupuncture targets nerves of the human body, and those nerves are indeed connected to the central nervous system. It is quite possible that hitting the right nerves “distracts” the brain such that it alleviates the sensation of pain coming from other parts of the body. This is not such a far-fetched claim, after all: compared to water memory, it looks like good science.
Rigorous studies of the effectiveness of acupuncture therefore seem to be worth much more attention and funding than those on homeopathy. And studies have been done and are under way, focusing on the different applications of nerve stimulation techniques. The methods of investigation typically consist in comparing the response to therapy of patients treated with acupuncture to that of patients where acupuncture was applied to random parts of the body, not targeting the nerves it is supposed to aim at.
I have taken some time today to have a look at all the studies I could locate in the library of the Cochrane Collaboration, a serious institution which reviews the results of clinical studies. The Cochrane collaboration web site contains more than two dozen studies addressing the effect of acupuncture and similar techniques on the treatment of specific pathologies. I put together a list of those studies below, quoting from their abstracts the conclusions they draw. An interesting picture emerges.
- Acupuncture for acute stroke: There is no clear evidence of benefit from acupuncture in acute stroke. […] Serious adverse effects were uncommon, and occurred in about one in every hundred patients treated.
- Acupuncture for insomnia: Currently there is a lack of high quality clinical evidence supporting the treatment of people with insomnia using acupuncture.
- Acupuncture for stroke rehabilitation: There is no clear evidence of the effects of acupuncture on stroke rehabilitation.
- Acupuncture-point stimulation for chemotherapy-induced nausea or vomiting: Electroacupuncture reduced first-day vomiting, but manual acupuncture did not. Acupressure reduced first-day nausea, but was not effective on later days. Acupressure showed no benefit for vomiting. Electrical stimulation on the skin showed no benefit. All trials also gave anti-vomiting drugs, but the drugs used in the electroacupuncture trials were not the most modern drugs, so it is not known if electroacupuncture adds anything to modern drugs. Trials of electroacupuncture with modern drugs are needed.
- Acupuncture and related interventions for smoking cessation: The review did not find consistent evidence that active acupuncture or related techniques increased the number of people who could successfully quit smoking. However, acupuncture may be better than doing nothing, at least in the short term; and there is not enough evidence to dismiss the possibility that acupuncture might have an effect greater than placebo.
- Acupuncture for dysphagia in acute stroke: Only one small randomised controlled trial was identified, involving 66 participants, which did not provide clear evidence of benefit from adding acupuncture to standard Western medical treatment. Considering the small sample size and methodological imperfections, there is insufficient evidence to determine the effectiveness of acupuncture.
- Acupuncture and assisted conception: The data from this meta-analysis suggests that acupuncture does increase the live birth rate with in vitro fertilisation (IVF) treatment when performed around the time of embryo transfer. However, this could be attributed to placebo effect and the small number of trials included in the review.
- Acupuncture for vascular dementia: There is no evidence from randomized controlled trials to determine whether acupuncture provides any effect when treating people with vascular dementia. Acupuncture is used to treat vascular dementia, but because no randomized controlled trials of acupuncture versus placebo were found, its efficacy and safety could not be analysed in this review. There is a need for randomized placebo controlled trials of acupuncture for people with vascular dementia.
- Acupuncture and electroacupuncture for the treatment of rheumatoid arthritis: In one study, people had acupuncture or fake therapy for five weeks, once per week. Pain, number of swollen and tender joints, disease activity, overall well-being, lab results, or amount of pain medication needed was about the same whether they had acupuncture or fake therapy. In the other study, people had acupuncture with an electric current going through the needles at specific or real acupuncture spots in the knee or at fake spots in the knee. Knee pain while at rest, while moving or while standing decreased more in the people who had the real acupuncture. The improvement lasted up to 4 months after acupuncture. Unfortunately, the authors of this review believe that this trial was of low quality and may overestimate how well acupuncture works.
- Acupuncture and dry-needling for low back pain: Thirty-five RCTs covering 2861 patients were included in this systematic review. There is insufficient evidence to make any recommendations about acupuncture or dry-needling for acute low-back pain. For chronic low-back pain, results show that acupuncture is more effective for pain relief than no treatment or sham treatment, in measurements taken up to three months. The results also show that for chronic low-back pain, acupuncture is more effective for improving function than no treatment, in the short-term. Acupuncture is not more effective than other conventional and “alternative” treatments. When acupuncture is added to other conventional therapies, it relieves pain and improves function better than the conventional therapies alone. However, effects are only small. Dry-needling appears to be a useful adjunct to other therapies for chronic low-back pain.
- Acupuncture for lateral elbow pain: Acupuncture might be able to provide short-term relief from tennis elbow, but moreresearch is needed.
- Acupuncture for migraine prophylaxis: We reviewed 22 trials which investigated whether acupuncture is effective in the prophylaxis of migraine. Six trials investigating whether adding acupuncture to basic care (which usually involves only treating acute headaches) found that those patients who received acupuncture had fewer headaches. Fourteen trials compared true acupuncture with inadequate or fake acupuncture interventions in which needles were either inserted at incorrect points or did not penetrate the skin. In these trials both groups had fewer headaches than before treatment, but there was no difference between the effects of the two treatments. In the four trials in which acupuncture was compared to a proven prophylactic drug treatment, patients receiving acupuncture tended to report more improvement and fewer side effects. Collectively, the studies suggest that migraine patients benefit from acupuncture, although the correct placement of needles seems to be less relevant than is usually thought by acupuncturists.
- Acupuncture for restless legs syndrome: There is insufficient evidence to support the use of acupuncture for the symptomatic treatment of restless legs syndrome. The review did not find consistent evidence to determine whether acupuncture is effective and safe in the treatment of RLS, based on the two trials identified. More high quality trials are warranted before the routine use of acupuncture can be recommended for patients suffering from RLS.
- Acupuncture for Bell’s palsy: This review aimed to review systematically all randomised controlled trials and controlled clinical trials, which examined the effectiveness of acupuncture for Bell’s palsy. Six studies including a total of 537 participants met the inclusion criteria. Five studies used acupuncture while the other used acupuncture combined with drugs. No trials reported on the outcomes specified for this review. Harmful side effects were not reported in any of the trials. Flaws in study design or reporting (particularly whether the process of assigning people to different groups was hidden and also substantial losses to follow-up), and clinical differences between trials prevented conclusions about the efficacy of acupuncture. The quality of the included trials was inadequate to allow any conclusion about theefficacy of acupuncture. More research with high quality trials is needed.
- Acupuncture for glaucoma: We did not find any randomized clinical trials on the subject. The limited information from a few case series highlights the gap in the existing evidence. At this point, the effectiveness of acupuncture as a therapeutic modality for glaucoma could not be established.
- Stimulation of the wrist acupuncture point P6 for preventing postoperative nausea and vomiting: Alternative methods, such as stimulating an acupuncture point on the wrist (P6 acupoint stimulation), have been studied in many trials. The use of P6 acupoint stimulation can reduce the risk of nausea and vomiting after surgery, with minimal side effects. Compared with antiemetic prophylaxis, P6 acupoint stimulation seems to reduce the risk of nausea but not vomiting.
- Acupuncture for depression: There are studies indicating a preference for treatment with self-help and complementary therapies for depression. This review examined the efficacy and adverse effects of acupuncture in treating depression. Based on the findings from seven trials of low quality, there is insufficient evidence to determine whether acupuncture is effective in the management of depression.
- Transcutaneous electrical nerve stimulation and acupuncture for primary dysmenorrhoea: The review of trials found high frequency TENS may help but there is not enough evidence to assess the effect of acupuncture or low frequency TENS. More research is needed.
- Interventions (other than pharmacological, psychosocial or psychological) for treating antenatal depression: There is not enough evidence available to determine if maternal massage or depression-specific acupuncture interventions are effective in treating antenatal depression. The review found only one trial involving 61 US women evaluating maternal massage and depression-specific acupuncture (the insertion of needles into the tissue for remedial purposes) for the treatment of antenatal depression. This trial provided insufficient evidence to determine if these therapies are effective treatment for antenatal depression. Further research is needed.
- Acupuncture for tension-type headache:We reviewed 11 trials which investigated whether acupuncture is effective in the prophylaxis of tension-type headache. Two large trials investigating whether adding acupuncture to basic care (which usually involves only treating unbearable pain with pain killers) found that those patients who received acupuncture had fewer headaches. Forty-seven percent of patients receiving acupuncture reported a decrease in the number of headache days by at least 50%, compared to 41% of patients in the groups receiving inadequate or ‘fake’ acupuncture. Three of the four trials in which acupuncture was compared to physiotherapy, massage or relaxation had important methodological shortcomings. Their findings are difficult to interpret, but collectively suggest slightly better results for some outcomes with the latter therapies. In conclusion, the available evidence suggests that acupuncture could be a valuable option for patients suffering from frequent tension-type headache.
- Auricular acupuncture for cocaine dependence:The authors searched the medical literature for studies called randomized controlled trials, in which one group of patients receives treatment (such as acupuncture) and is compared with a similar group who receives a different treatment or no treatment (the control group). The authors found seven studies with a total of 1433 people. Most of the studies compared acupuncture with ‘sham’ acupuncture in which needles were inserted into random places in the ear but not into the specific points required for treatment. The studies used a variety of acupuncture techniques, using three, four, or five of the treatment points. The studies had a number of problems with the way their results were reported. The authors conclude that there is no evidence that any form of auricular acupuncture is effective for treating cocaine dependence.
- Acupuncture for schizophrenia: This review identifies randomised controlled trials comparing acupuncture to antipsychotics and acupuncture combined with antipsychotics, to antipsychotics alone. The limited data we found provided mostly equivocal outcomes. Although some of the data did favour acupuncture when combined with antipsychotics, the results came from small studies, and further, more comprehensive trials are needed before we can confidently determine the efficacy of acupuncture in the treatment of schizophrenia.
- Acupuncture for chronic asthma: The studies included in the review were of variable quality and had inconsistent results. Future research should concentrate on establishing whether there is a non-specific component of acupuncture which benefits recipients of treatment. There should be an assessment not merely of placebo treatment, but also of ‘no treatment’ as well. There is insufficient evidence to make recommendations about the value of acupuncture as a treatment for asthma based on current evidence.
- Acupuncture for epilepsy: Patients with epilepsy are currently treated with antiepileptic drugs, but a significant number of people continue to have seizures and many experience adverse effects to the drugs. As a result there is increasing interest in alternative therapies and acupuncture is one of those. Eleven studies were included, however acupuncture has not yet been proven to be effective and safe for treating people with epilepsy.
- Acupuncture for neck pain: We included 10 trails (661 participants) in this review that examined the effects of acupuncture on neck pain for individuals with chronic neck pain (lasting for at least three months). One study also included individuals with neck pain that lasted for at least six weeks, but they considered it to be chronic. Acupuncture was compared to sham acupuncture, waiting list, other sham treatments (sham laser, sham TENS) or other treatments (mobilization, massage, traction). Acupuncture treatments appear to be safe and only minor, transient and benign adverse effects were reported in the trials. The trials were of moderate methodological quality, but the number of participants in each trial was relatively low. There was a range of individuals studied, acupuncture techniques used and outcomes measured, so we could not combine the results of the trials to get an overall picture of the effectiveness of acupuncture. Therefore, we could only draw limited conclusions. Individuals with chronic neck pain who received acupuncture reported, on average, better pain relief immediately after treatment and in the short-term than those who received sham treatments. Individuals with chronic neck pain with symptoms radiating to the arms who received acupuncture reported, on average, better pain relief in the short-term than those who were on a waiting list.
It thus seems that most studies claim the need for more investigations. Also, several methodological shortcomings affect the scientific value of a good portion of the studies. Not too surprising, after all. A few studies do report that acupuncture seems effective in treating selected chronical conditions. Several others seem to prove that the positive effects of acupuncture are of the same magnitude of those of random applications, leading to the conclusion that what works in acupuncture is the placebo effect. However, it seems to me that the last word is not spelt yet.
After reviewing those documents, I remain possibilistic. I am convinced that the placebo effect has a strong influence, possibly explaining all of the alleged beneficial effects of acupuncture. Whether the targeting of nerves does add benefits to the placebo effect is not proven, but might still be true, in specific cases. However, even if such benefits exists, they must be of very small entity, making me doubt that the technique will survive the verdict of a new generation of deeper scientific tests.
To conclude this post, to show that the scientific literature still is undecided on the issue, let me quote a 2005 document, a 300-page review of the treatment of acute pain, Acute Pain Management: Scientific Evidence (Australian and New Zealand College of Anaesthetists and Faculty of Pain Medicine), endorsed by the National Health and Medical Research Council (NHMRC). This exhaustive panoramic only has a single paragraph on acupuncture in Chapter 8:
Reviews of the effectiveness of acupuncture in an acute pain setting suggest that it may be useful for managing pain during childbirth (Smith et al 2003, Level I), idiopathic headache (Melchart et al 2001, Level I) and dental pain (Ernst & Pittler 1998, Level I). It may also be effective in treating postoperative pain. Both preoperative low and high frequency electro-acupuncture reduced postoperative analgesic requirements and the incidence of nausea and dizziness after lower abdominal surgery (Lin et al 2002, Level II). Acupuncture needles inserted preoperatively were also found to reduce postoperative pain, opioid consumption and nausea as well as plasma cortisol and adrenaline (epinephrine) levels (Kotani et al 2001, Level II).
Acupuncture may be effective in some acute pain settings (Level I).