So this morning I fired up my email only to find the following message from my Mum waiting for me.
These things may interest you: when I had acupuncture last week I asked if there was any scientific basis for it. She told me she had seen research where brain scans had been taken during acupuncture for pain relief (what I have) and they show increased activity. Also she has heard that it works on hot flushes in menopausal women (and not much else does!!!). I know you are skeptical but would it be interesting to look into? Its obviously a nerve/brain thing and I know you think its rubbish but it works and no one knows why.
First of all, props to my Mum for asking the all important question. It is always good to have a basic understanding of the evidence in support of any treatment you are undergoing, especially if you are paying for it. It’s also good to know if the person administering that treatment has an understanding of why they are doing what they are doing. Secondly, I want to note that the acupuncturist didn’t actually answer the question asked of her. My Mum asked if there was any scientific basis for acupuncture, and not if there was any evidence to support the idea that it works. Now this may sound like splitting hairs, and it is completely understandable that the acupuncturist answered as she did, but these are two very different questions with two very different answers.
So this short email from my Mum raises a number of points that need to be addressed. 1) Is there a scientific basis for acupuncture? 2) Is acupuncture effective at treating pain? 3) Is acupuncture effective at treating the symptoms of menopause? And 4) Is there an explanation for why acupuncture appears to work? Let’s take these questions in order shall we.
Is there a scientific basis for acupuncture?
So the first thing we need to cover is “what exactly is acupuncture?” Well the NHS define it like this:
Acupuncture is a treatment derived from ancient Chinese medicine in which fine needles are inserted at certain sites in the body for therapeutic or preventative purposes.
It is often seen as a form of complementary or alternative medicine (CAM), although it is used in many NHS general practices, as well as the majority of pain clinics and hospices in the UK.
I will skip over my horror at the last part of that second sentence, and also the claim that it is derived from “ancient Chinese medicine” (there is some evidence to suggest it is not). And for the time being I’m also not going to discuss the modern interpretations of how acupuncture is claimed to work, I will come to that later. What we are interested in here is the basis for the treatment. The NHS site continues:
Traditional acupuncture is based on the belief that an energy, or “life force”, flows through the body in channels called meridians. This life force is known as Qi (pronounced “chee”).
Practitioners who adhere to traditional beliefs about acupuncture believe that when Qi does not flow freely through the body, this can cause illness. They also believe acupuncture can restore the flow of Qi, and so restore health.
So acupuncture is said to work by relieving blockages in a person’s Qi flow by the insertion of needles at specific meridian points related to the condition that patient is suffering with, resulting in a rebalancing of their Qi and a return to health. So I guess the obvious question here is, is there any evidence that Qi even exists?
Well the simple answer is no, not really. For a start the concept of Qi doesn’t really fit with a biomedical understanding of how the body works, and indeed seems to be a purely hypothetical concept. Qi is basically a form of vitalism, the idea that living things differ from non-living things because they possess some non-physical aspect that non-living things do not. A vitalistic idea that most of us are more familiar with is the idea that living things have a soul. However, the concept of vitalism has long lacked any credibility in mainstream science, with the evidence in support of this rejection only growing stronger over time.
The idea that people have a life force or vital energy is not one accepted or supported by mainstream science. As such it seems obvious, to me at least, that any treatment modality based upon alterations to this life force would likewise lack a fundamental basis in science. Therefore, the answer the acupuncturist should have given in answer to my Mum’s question is “No, acupuncture does not have a scientific basis, because science does not support the existence of the underlying concept upon which it is based”.
Is acupuncture effective at treating pain?
Now you would imagine, given the answer to the previous question, that the obvious answer here would be no, of course not. Well, to steal a phrase from Ben Goldacre, I think you’ll find it’s a bit more complicated than that. For a start, you could jump on Google Scholar right now and quickly find a large number of published, peer reviewed, scientific papers that come to the conclusion that acupuncture is affective at treating pain. However, you would also find a large number of studies that have come to the opposite conclusion. Obviously this is a question without a simple yes or no answer. But before we start looking into the scientific evidence regarding the efficacy of acupuncture for treating pain, there is a concept we need to discuss first, and that’s the idea of sham acupuncture. According to the UK Health Centre website:
Sham acupuncture is essentially fake acupuncture, and is used as a control in scientific studies to determine whether or not the effects of a treatment are actually due to acupuncture treatment.
Sham acupuncture comes in a number of different types, which basically boil down to not actually sticking needles in people, sticking them in places not associated with a meridian point, or doing both. The idea is to try and account for all the aspects of undergoing an acupuncture treatment that are not directly related to the treatment itself. Or in other words, it is designed to account for the placebo effect, which we will discuss in more detail in a minute. A good study looking at the effectiveness of acupuncture will make use of sham acupuncture as a control. Doing this allows you to see if it is actually the acupuncture treatment that makes people feel better, as opposed to the effect of getting some sort of treatment compared to not getting any treatment.
Other things to be aware of are systematic reviews and meta analysis. Now while these are similar there are a number of important differences between then, however for the sake of brevity (yeah like I can be brief) I am going to count them as pretty much the same thing. Basically this is the process of bringing together a number of papers on a subject and re-examining them to see what conclusion can be drawn from them as a whole. This allows you to get a much clearer picture than you would from a single paper, and also gives you access to a far larger sample size than you would get with a single study.
So let’s take a look at a couple of studies. The first study I want to discuss looked at the psychological effects of acupuncture on back pain over time. I want to start with this study because the results actually show acupuncture having a positive effect. For the most part this seems to have been a pretty good study. It involved 485 patients recruited from 83 acupuncturists and measured their progress 2 weeks, 3, and 6 months after their treatment. On the down side, they did not make use of any control group, with no sham acupuncture being used and all participants receiving acupuncture as a treatment. As such it is difficult to tell whether acupuncture really had an effect, or if just getting some sort of treatment did…and this is kind of the point. So what did they find?
Illness perceptions and, to a lesser extent, self-efficacy and expectancies can usefully supplement variables from the fear-avoidance model in theorizing pain-related disability. Positive changes in patients’ beliefs about back pain might underpin the large nonspecific effects of acupuncture seen in trials and could be targeted clinically.
Er yeah, maybe I should explain that a bit. Basically what they found was that acupuncture did have a positive effect on how people felt about their back pain. So does this mean sticking needles into you reduces your pain? Well not really, and indeed the authors of the paper argue that the other aspects of acupuncture play an important role.
Indeed, acupuncture can be conceptualized as a complex intervention in which changes in patients’ health are produced not only by needling but also by more psychosocial factors such as empathic therapeutic relationships and holistic consultations in which discussions of lifestyle and self-care can trigger changes in how patients think and feel about their symptoms and their ability to manage them.
Here we can immediately see the importance of having a control group. If we know that there are psychosocial factors involved in making people feel better then how do we know if the needling does anything at all if we don’t test it by using sham acupuncture? Indeed, in a press release on this study the authors highlight the importance that psychology plays in the process.
People who started out with very low expectations of acupuncture – who thought it probably would not help them – were more likely to report less benefit as treatment went on.
If the patients didn’t believe it was going to work, then it didn’t work. Doesn’t that just scream “psychological response” at you? And can you think of any genuine medical treatment that works that way? Do you have to believe that an aspirin will work in order for it to treat your headache? Now don’t get me wrong, I am not saying these findings are not important, just that they don’t really show that the acupuncture treatment actually does anything. What they do show however is something I have long thought myself.
Dr Bishop added that to improve the effectiveness of treatment, acupuncturists should consider helping patients to think more positively about their back pain as part of their consultations.
Dr Stephen Simpson, director of research at Arthritis Research UK, said: “This study emphasises the influence of the placebo effect on pain. The process whereby the brain’s processing of different emotions in relation to their treatment can influence outcome is a really important area for research.
“Factors such as the relationship between practitioner and the patient can inform this and we should be able to understand the biological pathways by which this happens. This understanding could lead in the future to better targeting of acupuncture and related therapies in order to maximise patient benefit.”
Replace the word “practitioner” with “doctor”, and “acupuncture” with “scientifically efficacious medical treatments” and I could not agree more. When you go to the doctors you are often only in there a few minutes. More often than not they don’t really seem that interesting in you as a person, and they definitely don’t take the time to discuss how you are feeling about your illness, what ever it may be. What, I think, this study shows more than anything is the importance of treating the psychological aspects of a persons condition as well as the physical ones, and of doctors spending time with their patients (something I fully understand they can’t always do). But let’s move on before I get any more side tracked from the issue at hand.
Next up we have a couple of systematic reviews that combined looked at 61 different acupuncture studies. Between them these studies made use of a number of different control groups, namely no treatment, sham acupuncture, conventional therapy, and acupuncture in addition to conventional therapy. The findings are definitely interesting. In a review of studies looking at acupuncture as a treatment for lower back pain the authors found only a moderate effect of acupuncture over no treatment at all, but, more interestingly, they also found:
strong evidence of no significant difference between acupuncture and sham acupuncture, for short-term pain relief.
This finding is echoed by a review specifically looking at the effectiveness of acupuncture vs sham acupuncture.
Thirty-eight acupuncture trials were identified. Most studies (22/38 = 58%) found no statistically significant difference in outcomes, and most of these (13/22 = 59%) found that sham acupuncture may be as efficacious as true acupuncture, especially when superficial needling was applied to non-points.
What does this mean? Well what it seems to be saying is that thinking you are getting acupuncture has the same effect as actually getting acupuncture, and that getting some sort of treatment is better than not getting any treatment. But wait a moment, here’s a meta-analysis looking the effect of acupuncture on chronic pain that has come to a somewhat different conclusion.
Acupuncture is effective for the treatment of chronic pain and is therefore a reasonable referral option. Significant differences between true and sham acupuncture indicate that acupuncture is more than a placebo. However, these differences are relatively modest, suggesting that factors in addition to the specific effects of needling are important contributors to the therapeutic effects of acupuncture.
So what’s going on here? We seem to be getting conflicting results. Well let’s take a look at this meta-analysis a bit more closely. This paper looked at 29 different studies on a range of different chronic pain conditions, and which made use of both sham acupuncture and no acupuncture controls. Right, off to a good start, so what did they find?
To give an example of what these effect sizes mean in real terms, a baseline pain score on a 0 to 100 scale for a typical RCT [randomized controlled trials] might be 60. Given a standard deviation of 25, follow-up scores might be 43 in a no-acupuncture group, 35 in a sham acupuncture group, and 30 in patients receiving true acupuncture.
So what does this mean? Well assuming a starting pain value on a 0 to 100 scale of 60, they found that on average patients who had no acupuncture reported a 17% reduction in pain, those in the sham acupuncture group reported a 25% reduction, and those in the acupuncture group reported a 30% reduction, or in other words a 50% relative pain reduction. So let’s look at these comparisons. First, acupuncture vs no acupuncture. This is the largest effect reported, a 13% difference in pain reduction. But, as covered above, there are other possible explanations for this difference beyond “acupuncture works”, and the authors even highlight a very important one.
Because the comparisons between acupuncture and no-acupuncture cannot be blinded, both performance and response bias are possible.
Blinding is an important part of any good scientific study. In a single blinded study the patient doesn’t know if they are getting the real treatment or a sham, placebo treatment. This is designed to reduce the chance of them reporting they are feeling better just because they think they should be feeling better, something that happens all the time. The ideal however is a double blinded study. Here neither the patient or the person administering their treatment knows if they are getting the real deal or the placebo. This means that the doctor can’t accidentally, or intentionally, influence the results by suggesting to the patient that the treatment they are getting will or will not have an effect.
Now obviously this is not possible when you are comparing giving someone acupuncture with not giving them acupuncture. I mean, unless people really aren’t paying attention, there is a good chance that the patients will work out which group they are in. So straight away this finding is highly questionable. However, I am completely willing to accept the general conclusion that getting a treatment of some kind is more effective at reducing the subjective experience of pain than not getting a treatment. So what about the acupuncture vs sham acupuncture results? Well again blinding is an issue.
Similarly, while we considered the risk of bias of unblinding low in most studies comparing acupuncture and sham acupuncture, health care providers obviously were aware of the treatment provided, and, as such, a certain degree of bias of our effect estimate for specific effects cannot be entirely ruled out.
Ok so there may have been some bias effect on the results, but come on, the meta-analysis still reported a statistically significant difference between the acupuncture group and the sham acupuncture group, with the acupuncture group reducing pain more. What more do you want man??? Well the difference between the groups being reported is just 5%. The acupuncture group reported 5% less pain on average than the sham acupuncture group. Now this may be statistically significant, but does it really mean anything in a clinical setting? If you were asked to rate your level of pain on a scale from 0 to 100, do you really think you could accurately tell the difference between a pain level of 30 and one of 35? Throw in the effect that bias may have had (as well as the fact that three of the studies by Vas et al reported results 5 times higher than the average) and that 5% difference pretty much disappears.
So once again what we find from this analysis is that getting some sort of acupuncture treatment is better at reducing pain than not getting any treatment, but that it really doesn’t matter if the treatment you get is real or not.
Now before I move on to the next question, this is going to be the longest post ever isn’t it, it is only fair that I cover the evidence actually mentioned by the acupuncturist to my Mum. Namely brain scans showing that acupuncture is effective at reducing pain. Straight off I have to say that I have no idea which study the acupuncturist was referring to, there a rather a few of them, so what I am going to do is pick a couple of papers that were written by researchers favourable towards acupuncture and briefly (ha!) discuss what their results mean.
First up we have a study that used PET scans to examine the effectiveness of acupuncture at relieving pain in people suffering from osteoarthritis. In this study 14 patients were given one of three forms of acupuncture, real acupuncture, sham acupuncture, or a simple skin-prick. Patients were blinded as to which treatment they were getting, woo hoo. So what did this study find?
The three interventions, all of which were sub-optimal acupuncture treatment, did not modify the patient’s pain.
Well that’s not a great start. I mean the entire point of the treatment is to reduce pain, but according to this study that didn’t happen. But let’s ignore that for the moment, I am sure it is not important, and look at what else they found.
The insula ipsilateral to the site of needling was activated to a greater extent during real acupuncture than during the placebo intervention. Real acupuncture and placebo (with the same expectation of effect as real acupuncture) caused greater activation than skin prick (no expectation of a therapeutic effect) in the right dorsolateral prefrontal cortex, anterior cingulate cortex, and midbrain. These results suggest that real acupuncture has a specific physiological effect and that patients’ expectation and belief regarding a potentially beneficial treatment modulate activity in component areas of the reward system.
So, in short, really sticking a needle into someone has a greater physiological effect than just pretending to stick a needle into them, and thinking you were getting a real treatment, whether you were or not, had a greater effect than thinking you weren’t getting a real treatment. This seems to agree with the other studies we have discussed so far. Ok, next.
The next paper I want to mention is a systematic review of studies investigating acupuncture using brain imaging techniques. They looked at 22 different studies that used functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) scans to look at brain activation whilst undergoing acupuncture treatment. And the results show…
Acupuncture clearly affects this [pain] matrix in both specific and non-specific manner that is consistent with its specific clinical effects, as well as the effects of expectation on pain relief.
So the areas of the brain effected are consistent with both acupuncture and the placebo effect? Do go on.
It appears that there are substantial overlaps between the pain matrix that have already been identified within the brain and its response to placebo acupuncture and pain. There is also considerable overlap between the areas of placebo response and expectation and acupuncture
So again, there are considerable overlaps in the areas of the brain effected by acupuncture and the areas effected by the placebo effect. Does this not tell you something? Ok, that’s it, let’s finally move on to the next question.
Is acupuncture effective at treating the symptoms of menopause?
I’ll try to go through this quickly, this post is already way too long. Let’s jump right into the studies. The first one is a systematic review looking at acupuncture as a treatment for menopausal hot flushes. The review looked at six studies that made use of sham acupuncture controls. And the results say…
Sham-controlled RCTs fail to show specific effects of acupuncture for control of menopausal hot flushes.
Well that’s pretty clear, next. The other study I found on this issue at first glance seems more positive. This study again looked at the effect of acupuncture on hot flushes in menopausal women. There were two groups, one that received acupuncture and advice on self-care, and a control group that just got self-care advice.
Hot flash frequency decreased by 5.8 per 24 hours in the acupuncture group (n = 134) and 3.7 per 24 hours in the control group (n = 133), a difference of 2.1 (P < 0.001). Hot flash intensity decreased by 3.2 units in the acupuncture group and 1.8 units in the control group, a difference of 1.4 (P < 0.001). The acupuncture group experienced statistically significant improvements in the vasomotor, sleep, and somatic symptoms dimensions of the Women's Health Questionnaire compared with the control group.
Hmm, interesting, and their conclusion.
Acupuncture plus self-care can contribute to a clinically relevant reduction in hot flashes and increased health-related quality of life in postmenopausal women.
But is this really what the results show? Well, to be honest, we don’t know. As I am sure you will have noticed they did not make use of sham acupuncture in this study. As such we don’t know if it was the acupuncture specifically that caused this increased reduction in hot flushes, or if just getting some sort of treatment, compared with no treatment, was responsible. To me the conclusion of this study might as well have been “the placebo effect plus self-care advice is more effective than self-care advice alone”. Now that’s a conclusion that I have no doubt is true.
Is there an explanation for why acupuncture appears to work?
I am willing to bet that you can guess what my answer to this question is going to be. That’s right, I personally think that all of the supposed effects of acupuncture can be explained by the placebo effect. The placebo effect is, very basically, where something that is not a treatment for a condition has an effect on that condition because the person believes it will. The placebo effect is a fascinating thing that to be honest we don’t fully understand yet, but we do know it can produce measurable effects on conditions such as pain and menopause. I discuss it in more detail in my book (cough, shameless plug, cough). If you have the time I recommend you read this article about a former acupuncturist who now studies the placebo effect.
So does acupuncture work? Well to be honest the answer to that question really depends on what you mean by “work”. If by “work” you mean “does getting acupuncture treatment have a significant measurable effect on reducing the perception of pain over not getting the treatment?”, then I would say that the answer is yes. If however by “work” you mean “does acupuncture actually have any effect beyond the placebo effect?”, then I would have to say no.
At the end of the day my thoughts on the issue are this. If you feel that acupuncture is for you, and that going to get the treatments makes you feel better, then I say go for it, you don’t really have anything to lose (aside from a bit of cash). Just please, please consult your doctor before doing so or if your symptoms get any worse. Never, ever use acupuncture as a replacement for real medical treatment. And hey, there is good evidence to suggest that the placebo effect works even when you know about it, so if you go to your acupuncturist with a positive attitude and the expectation it will make you feel better, then it probably will even though you now know it’s not really doing anything.