stroke
After a traumatic brain injury (TBI) the risk of stroke is significantly increased. Taiwanese researchers conducted a study to find out whether acupuncture can help to protect TBI patients from stroke. They used Taiwan’s National Health Insurance Research Database to conduct a retrospective cohort study of 7409 TBI patients receiving acupuncture treatment and 29,636 propensity-score-matched TBI patients without acupuncture treatment as controls. Both TBI cohorts were followed for up to two years and adjusted for immortal time to measure the incidence and adjusted hazard ratios (HRs) of new-onset stroke.
TBI patients with acupuncture treatment (4.9 per 1000 person-years) had a lower incidence of stroke compared with those without acupuncture treatment (7.5 per 1000 person-years), with a HR of 0.59 (95% CI = 0.50-0.69) after adjustment for sociodemographics, coexisting medical conditions and medications. The association between acupuncture treatment and stroke risk was investigated by sex and age group (20-44, 45-64, and ≥65 years). The probability curve with log-rank test showed that TBI patients receiving acupuncture treatment had a lower probability of stroke than those without acupuncture treatment during the follow-up period (p<0.0001).
The authors conclude that patients with TBI receiving acupuncture treatment show decreased risk of stroke compared with those without acupuncture treatment. However, this study was limited by lack of information regarding lifestyles, biochemical profiles, TBI severity, and acupuncture points used in treatments.
I want to congratulate the authors for adding the last sentence to their conclusions. There is no plausible mechanism that I can think of by which acupuncture might bring about the observed effect. This does not mean that an effect does not exist; it means, however, that it is wise to be cautious and to not jump to conclusions which later need to be revised. The simplest interpretation, by far, of the observed phenomenon is that those patients opting to have acupuncture were, on average, less ill and therefore had a lower risk of stroke.
Having said that, the findings are, I think, intriguing enough to conduct further investigations – provided they are rigorous and eliminate the confounders that prevented this study from arriving at more definitive conclusions.
A stroke is a condition where brain cells get irreversibly damaged either by a haemorrhage in the brain or by a blood clot cutting off oxygen supply. This process leaves most patients with neurological deficits such as difficulties in moving, speaking, concentrating etc. As other parts of the brain learn to take over, these problems can partly or completely resolve themselves over time, but many patients are left with permanent handicaps. Stroke-rehabilitation can minimise these problems, and there is a long-standing debate as to which measures are most effective. Acupuncture has been discussed as a method to improve the results of stroke-rehabilitation, but the evidence is hotly disputed. This is why a new study in this area is an important contribution to our existing knowledge.
The aim of this randomised trial was to test the effectiveness of acupuncture in promoting the recovery of patients with ischaemic stroke and to determine whether the outcomes of combined physiotherapy and acupuncture are superior to those with physiotherapy alone. The Chinese investigators recruited 120 patients who received one of three daily treatments: 1) acupuncture, 2) physiotherapy, 3) physiotherapy combined with acupuncture. Motor function in the limbs was measured with the Fugl-Meyer assessment (FMA); the modified Barthel index (MBI) was used to rate activities of daily living; both of these measures are validated and well-established. All evaluations were performed by assessors blinded to treatment allocation.
At baseline, FMA and MBI scores did not significantly differ among the treatment groups. Compared with baseline, on day 28 of therapy, the mean FMA scores of the physiotherapy, acupuncture, and combined treatment groups had increased by 65.6%, 57.7%, and 67.2%, respectively; on day 56, FMA scores had increased by 88.1%, 64.5%, and 88.6%, respectively. The respective MBI scores in the three groups had increased by 85.2%, 60.4%, and 63.4% at day 28 and by 108.0%, 71.2%, and 86.2% at day 56, respectively. However, FMA scores did not significantly differ between the three treatment groups on the 28th day. By the day 56, the FMA and MBI scores of the physiotherapy group were 46.1% and 33.2% greater, respectively, than those in the acupuncture group. No significant differences were seen between the combined treatment group and the other groups. The FMA subscores for the upper extremities did not show significant improvements in any group on day 56.
The authors draw the following conclusion: “Acupuncture is less effective for the outcome measures studied than is physiotherapy. Moreover, the therapeutic effect of combining acupuncture with physiotherapy was not superior to that of physiotherapy alone. A larger-scale clinical trial is necessary to confirm these finding.”
Our own study arrived at similarly disappointing conclusions: “Acupuncture is not superior to sham treatment for recovery in activities of daily living and health-related quality of life after stroke, although there may be a limited effect on leg function in more severely affected patients“. Our review of all 10 sham-controlled RCTs in this area is also in line with the results of this new study: “Our meta-analyses of data from rigorous randomized sham-controlled trials did not show a positive effect of acupuncture as a treatment for functional recovery after stroke”
I am quite sure that some acupuncture-enthusiasts will dispute this evidence. They might argue that I am too critical, the trials were not done optimally, that acupuncturists have seen plenty of good results in their clinical practice, that acupuncture is a complex intervention that does not fit into the straight jacket of an RCT, that this or that “prestigious” organisation recommends acupuncture for stroke patients, that it would be wrong not to give acupuncture a try etc. etc. I would counter that the reliable evidence available to date is sufficiently conclusive to stop claiming that acupuncture is effective and thus give false hope to severely suffering, vulnerable patients. Moreover, I would advocate using the sparse available resources to help stroke victims with treatments that demonstrably work.
Even though I have not yet posted a single article on this subject, it already proved to be a most controversial subject in the comments section. A new analysis of the evidence has just been published, and, in view of the news just out of a Royal Charter for the UK College of Chiropractors, it is time to dedicate some real attention to this important issue.
The analysis comes in the form of a systematic review authored by an international team of chiropractors (we should not fear therefore that the authors have an “anti-chiro bias”). Their declared aim was “to determine whether conclusive evidence of a strong association [between neck manipulation and vascular accidents] exists”. The authors make it clear that they only considered case-control studies and omitted all other articles.
They found 4 such publications all of which had methodological limitations. Two studies were of acceptable quality, and one of these studies seemed to show an association between neck manipulation and stroke, while the other one did not. The authors’ conclusion is ambivalent: “Conclusive evidence is lacking for a strong association between neck manipulation and stroke, but it is also lacking for no association”.
The 4 case-control studies, their strength and weaknesses are, of course, well-known and have been discussed several times before. It was also known that the totality of these data fail to provide a clear picture. I would therefore argue that, in such a situation, we need to include further evidence in an attempt to advance the discussion.
Generally speaking, whenever we assess therapeutic safety, we must not ignore case-reports. One might be next to meaningless but collectively they can provide strong indicators of risk. In drug research, for instance, they send invaluable signals about potential problems and many drugs have been withdrawn from the market purely on the basis of case-reports. If we include case-reports in an analysis of the risks of neck manipulations, the evidence generated by the existing case-control studies appears in a very different light. There are virtually hundreds of cases where neck manipulations have seriously injured patients, and many have suffered permanent neurological deficits or worse. Whenever causation is validated by experts who are not chiropractors and thus not burdened with a professional bias, investigators find that most of the criteria for a causal relationship are fulfilled.
While the omission of case-reports in the new review is regrettable, I find many of the staements of the authors helpful and commendable, particularly considering that they are chiropractors. They seem to be aware that, when there is genuine uncertainty, we ought to err on the safe side [the precautionary principle]. Crucially, they comment on the practical implications of our existing knowledge: “Considering this uncertainty, informed consent is warranted for cervical spinal manipulative therapy that advises patients of a possible increase in the risk of a rare form of stroke…” A little later, in their discussion they write: “As the possibility of an association between cervical spinal manipulative therapy and vascular accidents cannot be ruled out, practitioners of cervical spinal manipulative therapy are obliged to take all reasonable steps that aim to minimise the potential risk of stroke. There is evidence that cervical rotation places greater stresses on vertebral arteries than other movements such as lateral flexion, and so it would seem wise to avoid techniques that involve full rotation of the head.”
At this point it is, I think, important to note that UK chiropractors tend not to obtain informed consent from their patients. This is, of course, a grave breach of medical ethics. It becomes even graver, when we consider that the GCC seems to do nothing about it, even though it has been known for many years.
Is this profession really worthy of a Royal Charter? This and the other question raised here require some serious consideration and discussion which, no doubt, will follow this short post.
