familial hemiplegic migraine

30 March 2012

Watch for it – Ketamine for Migraine and More

James Discoveries & Stats, Medications, Treatments 6

Using ketamine for pain is not a new idea. But I think we’re going to see it get an increasing amount of attention in the months ahead.

A few weeks ago, NPR featured a news story on the use of ketamine for depression. Ketamine, originally developed as a human anaesthetic, has since been used for various applications in medicine.

Ketamine for depression, migraine, and more?

It’s also used as an illegal drug, gaining fame as "K", "Vitamin K" or "Special K".

In recent years there has been sporadic interest in using ketamine for pain. It’s a difficult drug to study, because it tends to be rather obvious that you’ve taken it.

But it has been suggested as a treatment for cluster headache, familial hemiplegic migraine, chronic daily headache, and migraine, as well as other types of pain.

Ketamine is a neurological drug, classed as a NMDA (N-methyl-D-aspartate) receptor antagonist. It is believed to work in a number of different ways in the brain – relating to calcium channels, serotonin, and glutamate – terms that will be familiar with migraine researchers in particular. In fact, ketamine has been especially useful in the treatment of headache or migraine that just won’t go away and isn’t responding to other kinds of treatment (refractory). It’s given as an IV or intranasal treatment. Of course, this means it’s way down on the list of treatments that will be given – it’s rare and even when it’s tried it’s often not successful.

However, with the growing interest in ketamine for depression, the game changes. You can bet that there will be increased interest in ketamine for chronic pain conditions, which often come hand in hand with depression.

Although increased interest doesn’t mean this should be the drug of choice for most people, it does mean that more research will be done. It may be a treatment that will help a few patients whose pain is seemingly unstoppable.

For more on the background of ketamine, read Ketamine and MDARs in the treatment of neuropathic pain from Dr. Jan M. Keppel Hesselink. For a review of the studies on ketamine for other types of pain aside from headache, read Ketamine in Chronic Pain Management: An Evidence-Based Review

31 March 2010

Familial Hemiplegic Migraine 1 – Not Always the Same

James Discoveries & Stats 2

Familial Hemiplegic Migraine 1 (FHM1) is a rare type of migraine related to the gene locus CACNA1A. Common to FHM1 are speech, visual and sensory disturbances, headache, and loss of coordination (read more about Familial Hemiplegic Migraine here).

DNA display at
Oxford University Natural History Museum
Photo courtesy of net efekt

The fascinating thing about migraine that is familial – that clearly runs in families (although most migraine may be genetically based) is that it’s possible to study genetic connections.

Using these connections,researchers have classified different types of FHM – numbering them 1, 2 and so on (more on types of FHM).

But even within these sub-groups of a specific type of migraine, there are differences. A recent study (published in January) focused on two different CACNA1A mutations – S218L and R192Q. The former, S218L, is associated with more severe versions of FHM.

To understand the study, you need to understand that cortical spreading depression (CSD), a type of "storm" that sweeps across the brain, seems to be key to the progression of migraine symptoms. Not just in FHM, but probably in all types. (more on the science of migraine here)

The finding, in mice, was that those with the S218L mutation were far more susceptible to CSD. It took less stimuli to get one started, and often one "push" would cause multiple CSD events.

For those with the R192Q mutation, just one event was harder to start.

What does this matter? Well, obviously for those with familial hemiplegic migraine this may lead to better diagnosis and treatment.

However, it’s also doing two things for all migraine patients. First, it’s helping us understand more about how cortical spreading depression works. Second, there may be a much wider group of migraineurs that have a similar or identical mutation. Many with more common types of migraine have mutations in the gene locus CACNA1A.

In fact, it’s not only migrainuers we’re talking about. Other disorders may be involved, including those with nystagmus (involuntary movement of the eyeballs) and ataxia (unsteadiness, loss of muscle coordination), and seizures. Head trauma has also been related to this gene mutation. The connection between S218L and the calcium channels are also of interest as the study of calcium channels and migraine is of great interest in current research.

More on this study: High cortical spreading depression susceptibility and migraine-associated symptoms in Ca(v)2.1 S218L mice.
More on FHM1, seizures and head trauma
Electroencephalographic changes and seizures in familial hemiplegic migraine patients with the CACNA1A gene S218L mutation

25 October 2008

Vestibular Migraine – Why the confusion?

James Information 5

It’s been in the news a lot lately – vestibular migraine. You can be excused if you’ve never heard of such a thing before. It’s not that lots of people don’t have it – in fact, I have a friend that does. The confusion lies in the name.

Vestibular Migraine is not the official name of any type of migraine at all. It’s better to see it as a description – a migraine with certain symptoms. The name is used, but rarely because it’s not listed in the official list of classifications from the International Headache Society.

The word "vestibular" simply means having to do with equilibrium. So, as you may guess, a migraine attack which is vestibular involves symptoms such as vertigo, dizziness, motion sensitivity, etc. (more on vestibular migraine symptoms from Johns Hopkins).

So we’re not going to say there’s "normal" migraine and "vestibular" migraine, as if there are two types. Migraine is a disease with a host of symptoms. Often those symptoms allow us to narrow down which treatment will work the best. Migraine disease has been broken down into many different types.

The type of migraine most commonly associated with vertigo is called basilar-type migraine (formerly called basilar migraine or basilar artery migraines). Vertigo is common in basilar type migraine, as is ringing in the ears, unsteadiness, visual symptoms, and sometimes a decreased level of consciousness. Another type of migraine, familial hemiplegic migraine, sometimes has similar symptoms, except with motor weakness added on. In both cases there is usually a headache.

Vestibular migraine can also be a form of migraine with aura, when the aura is vertigo or dizziness. In fact, many migraineurs experience dizziness, but when it becomes particularly overwhelming and severe, that’s when we start using the word "vestibular".

And remember, these types of migraine attacks involve lots of other symptoms beyond headache, vertigo and dizziness (such as the symptoms mentioned above). Most migraine attacks can be debilitating for a host of reasons, not just because of the headache pain. Even if there is no headache pain, the vertigo or dizziness can be frightening, and this and the many other symptoms can shut you down completely during an attack.

One type of headache that sometimes comes with dizziness is an MSG headache. MSG headache can be a migraine or not.

If you are having vestibular symptoms, it’s important not to make assumptions. See your doctor and have other causes ruled out first. (Sometimes an EEG is helpful in cases like these). Then you can investigate treatments, which generally are common to most types of migraine.

Sometimes regular migraine treatments can alleviate all the symptoms, but sometimes the vertigo remains. It’s possible to take medication for the vertigo as well.

Vestibular migraine - vertigo, dizziness, and more...

12 July 2008

Genetic mutations, migraine auras, and epilepsy

James Discoveries & Stats, Medications 0

Genetic research into migraine continues to suggest directions of treatment that haven’t been widely considered before. The latest studies out of the Vanderbilt University Medical Center in the USA are doing just that, and also increasing interest in studying links between migraine and epilepsy.

Here’s the story in brief. The study is about a rare form of migraine known as Familial Hemiplegic Migraine type 3. Studies of FHM have helped us understand genetic markers in the past. Often the focus has been on what are called calcium channels in the body.

But the new research is focusing on something different – sodium channels. A mutant gene causes problems with the normal functioning of the calcium channel in the body. Sodium channels act as "gateways" to allow sodium into the cell. When the channel gets "stuck" open, too much sodium gets through.

It may be that the genetic problem is involved in causing the cortical spreading depression in the brain, which comes early in the migraine chain of events.

Though FHM3 is not a common form of migraine, there may be some similarities here with more common forms. And it looks like drugs that act as sodium channel blockers may be worth further investigation.

The team at Vanderbilt University was studying the same gene for epilepsy issues. Finding a common cause between migraine and epilepsy could strengthen the suspected link between the two diseases.

The Vanderbilt Medical Center has an article on this research published yesterday if you want more depth – Mutations reveal clues to biological basis of migraines.

19 March 2005

More on hemiplegic migraine

James Website news 0

One area that has benefited from genetic study is in the rare form of migraine known as familial hemiplegic migraine. As genetic mutations have been discovered, we have gained a better understanding of how this type of migraine works, how to diagnose it and how to treat it.

Familial hemiplegic migraine is a type of migraine with aura, and is one of the more severe types of migraine that can cause stroke-like symptoms – weakness on one side of the body, trouble speaking, and a pins-and-needles sensation. There is a genetic (family-familial) connection, related to the calcium channels in the body. As seems to be the case in many migraine types, the body is getting the wrong neurological signals. Some of this testing is still in the research stages, and it’s not yet foolproof, but it’s a tremendous advantage to earlier guesswork.

There’s a bit of an update now online of the original December article on headache and hemiplegic migraine, including more specifics and references. It’s still just an overview – watch for more!