Introduction

Today I came across a new study by Yarnitsky et al [1] which shows promising results for treating migraine using an electronic stimulation device worn on the arm.

As someone who suffers from episodic migraines I am always on the lookout for new treatments.

Although a lot of drug based treatments are available, they have their own unique side effects which can be problematic.

For example I use Sumatriptan (thought to work by constricting blood vessels in the brain) - unfortunately this can cause constriction of blood vessels in other parts of the body which can be uncomfortable and in certain cases dangerous.

A safe, tolerable, non-drug based alternative would certainly be very useful.

How is this different?

(N.B. Image is of TENS machine electrodes from Thinkstock. I wasn't able to find images of the actual device used in time for the post.)

Previous research along similar lines uses devices that need to be more precisely located in the face or head region.

This makes them less convenient to use.

The device used here is called Nerivio Migra:

[It] consists of a pair of rubber electrodes mounted on an armband with a power source, controlled by the patient’s smartphone, via a custom-made application.

Patients are easily able to apply it to one of their arms without any assistance and it is easy to hide.

Methods

The study asked patients to use the Nerivio Migra device within 20 minutes of onset of a migraine.

Previous research has indicated that earlier treatment (when the pain level is lower) tends to be more effective.

The devices were designed to give patients either active treatment or an inactive "sham" treatment to act as a placebo.

A number of different types of information were collected including people's level of pain.

Results

The devices worked very well - 64% of patients with active treatment had a greater than 50% reduction in pain.

This compares to a rate of 26% for placebo.

The extent of pain relief was almost identical to that for triptan medications (the type which I use).

As the authors state:

Interestingly, our extent of pain relief is almost identical to that reported for triptans: 59% transition from severe/moderate to mild/no pain for triptans parallels the 58% reported here; 29% and 30% are the respective numbers for transition to no pain.

This suggests that this type of treatment could be used as an alternative to conventional medical treatments.

Equally importantly the devices were well tolerated. Most people found the stimulation to be pleasant.

Patients were asked to rate the treatment for how much of a burden it was, the mean score (2.5) was between "neutral" and "not at all".

On rating "ease of use" the mean score fell between "easy and very easy".

How does it work?

The short answer is that we don't fully understand.

The authors suggest this treatment utilises an effect known as Conditioned Pain Modulation (CPM).

According to Nir and Yarnitsky [2] :

"[CPM] has been described using various terms, including ‘diffuse noxious inhibitory controls’, ‘counterirritation’, and ‘heterotopic noxious counter-stimulation’."

According to them previous research has suggested that one form of pain (noxious stimulus) can actually inhibit another form of pain.

This study suggests that reducing the intensity of the painful stimulus to below the pain threshold still works in inhibiting the pain.

Studies on CPM suggest that the pain relief relates to local, spinal cord and brain effects (involving a variety of regions).

The specifics of this are still a matter of debate although it appears the brainstem plays an important role.

I suspect the mechanism might well be the same for CPM, acupuncture and also for the natural, reflexive response of massaging an injured body part.

Problems

As is often the case this was a relatively small study.

71 patients comprised the final sample (with a total of 299 treatments).

I have described many times before how small sample sizes can reduce the statistical strength of results.

There was also a gender imbalance with significantly more women (69) than men (17) - this might reduce the validity of the results in men.

This is a double blind study but as the authors themselves point out, it can be difficult to blind people fully to sham treatment.

They will likely be able to feel the difference between it and active treatment.

This was suggested by the fact that those receiving sham were less likely to complete the full (20 minutes of) treatment.

Perhaps they realised they were receiving the sham and ended it early because they didn't expect any benefit.

Conclusion

This is certainly a fascinating preliminary study.

It suggests that a simple form of electrical stimulation may be able to treat migraines as effectively as one of the leading class of drugs (triptans) without the potentially serious side effects.

It also seems to be better tolerated, less obtrusive (arm vs head) and easier to apply and use than alternative methods that work using similar principles.

I would feel much more comfortable wearing an arm worn device (vs head worn) if I was at work or in public.

The authors even point out that it can easily be hidden under a sleeve.

As is often the case this is early research and I do hope that this can be confirmed with larger studies.

If that happens then we could end up with a safer and better tolerated migraine treatment which would be of great use to those of us who suffer with this problem.

What do you think?

As always let me know what you think in the comments.

Thank you for reading

References

Yarnitsky, David, Lana Volokh, Alon Ironi, Boaz Weller, Merav Shor, Alla Shifrin, and Yelena Granovsky. 2017. “Nonpainful Remote Electrical Stimulation Alleviates Episodic Migraine Pain.” Neurology, March. doi:10.1212/WNL.0000000000003760.
Nir, Rony-Reuven, and David Yarnitsky. 2015. “Conditioned Pain Modulation.” Current Opinion in Supportive and Palliative Care 9 (2): 131–37.

Arm-Worn Electrical Device Could Treat Migraine as Effectively as Medication