Image credit: Wellcome Images, Wellcome Library, London, via Wikimedia Commons.

Image credit: Wellcome Images, Wellcome Library, London, via Wikimedia Commons.

Last week I gave a quick overview of standard treatment options for migraine, a severe form of recurrent headaches. As promised, this week I will address some common treatments for migraine that I don’t think are supported by the evidence.

Acupuncture

Acupuncture is the CAM modality that, it seems to me, has infiltrated the furthest into mainstream medicine, including for the treatment of migraine. In fact the The American Headache Society includes acupuncture on its list of recommended treatments. The reason for this is that acupuncture proponents have been able to change the rules of clinical research so that essentially negative or worthless studies of acupuncture are presented as positive.

I reviewed the evidence for acupuncture and migraine previously, demonstrating the multiple problems with the acupuncture literature in general, and specifically acupuncture in migraines. Most studies suffer from at least one fatal flaw: they are not properly blinded, they do not include a control, they mix acupuncture with non-acupuncture variables (mostly including electrical stimulation in the treatment group), comparison groups are not adequately treated, they make multiple comparisons to maximize chance outcomes, or they are simply too small making them susceptible to all the usual problems of bias in research.

What we don’t see is a consistent and clinically-relevant effect in properly-controlled double-blind trials where the variables of acupuncture are isolated.

As with the rest of acupuncture research, what the results actually show is that when you do properly isolate the variables, the location or insertion of needles do not seem to matter, consistent with the interpretation that acupuncture is an elaborate placebo.

The best demonstration of the persistent positive bias in interpreting acupuncture studies by acupuncture proponents is the 2009 Cochrane review of acupuncture in migraine (the latest version). After saying that acupuncture may work, they acknowledge:

There is no evidence for an effect of ‘true’ acupuncture over sham interventions, though this is difficult to interpret, as exact point location could be of limited importance.

This is not difficult to interpret at all. The properly-blinded comparisons are negative. Only unblinded results are encouraging. This makes acupuncture the equivalent of N-rays – not a real phenomenon.

Electrical stimulation

Using either electrical or magnetic stimulation to alter brain function for therapeutic purposes is an emerging and interesting treatment modality. However, I don’t think we are quite there yet.

Last March the FDA approved the first device for the treatment of migraines with electrical stimulation, the Cephaly device. Approval was based upon two studies, which I reviewed at the time.

The FDA cited two studies in support of the device. The first was an unblinded pilot study looking at patient satisfaction (not efficacy). The second study involved 67 subjects and was placebo controlled. However – the results were negative. There was no statistically-significant difference between the treatment and the control group. The study concluded, however, that the treatment showed a statistically significant difference from baseline while the placebo did not. This is not an appropriate statistical comparison, but it is a very common error. This study should be considered negative, but was used as the basis for FDA approval.

At present I would consider this approach experimental but plausible. Real efficacy still needs to be demonstrated. Further, there are multiple possible stimulation sites (occipital nerve vs. frontal stimulation) and multiple intensities and durations need to be explored, both for acute migraine and prevention. It will likely still be a few years before we can make solid conclusions about this approach.

Chiropractic

Cervical manipulation for migraine headache is commonly offered by chiropractors. The research here is very heterogeneous, partly because there are many subtypes of headaches, some of which involve neck pain, restricted range of motion, or muscle tightness. Physical therapy can be helpful in such cases, but there is no reason to use anything other than the most gentle of interventions, such as massage, or mobilization when necessary.

Studies specifically of chiropractic show, ironically, no benefit for tension headaches. Studies with migraine are of limited rigor. A 2004 Cochrane review (the latest available) concluded:

A few non-invasive physical treatments may be effective as prophylactic treatments for chronic/recurrent headaches. Based on trial results, these treatments appear to be associated with little risk of serious adverse effects. The clinical effectiveness and cost-effectiveness of non-invasive physical treatments require further research using scientifically rigorous methods. The heterogeneity of the studies included in this review means that the results of a few additional high-quality trials in the future could easily change the conclusions of our review.

The old, “More research is needed,” which is essentially a euphemism for, “current research does not demonstrate efficacy.”

The reviews all seem to still rely heavily on one study from 1998 comparing spinal manipulation to amitriptyline, which is considered an accepted treatment for the prevention of migraine. The study, however, was short, only an 8 week treatment period and 4 week follow up. This is often how long it takes for amitriptyline to start working. They also used a low dose of amitriptyline, which is often subtherapeutic. The fact that there was no difference between manipulation and a short course of low dose amitriptyline is not impressive, and likely represents lack of efficacy for both.

At present there is insufficient evidence to recommend manipulation for migraine treatment or prevention. In patients with neck pain or symptoms associated with their headaches, simple physical therapy or massage is a reasonable option, but also has little evidence for efficacy. There are a few small studies of massage with positive results, and “more research is needed.”

Conclusion

There are many other treatments offered for migraines that are of dubious evidence or plausibility, but I can’t cover them all in one article. The three above are the most common.

Reviewing the literature one common theme keeps cropping up – most studies are of such limited scientific rigor that their conclusions of are little or no value. Most such studies are false positives and simply reflect the bias of the researchers. It is unfortunate that so many studies of preliminary design continue to be done even in areas that are far beyond the preliminary stage. We don’t need another pilot study of acupuncture for migraine. What we need are rigorous placebo-controlled trials.

It is disappointing that in some cases definitive trials have not been done even after decades of use.

 

 

Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the president and co-founder of the New England Skeptical Society, the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also contributes every Sunday to The Rogues Gallery, the official blog of the SGU.