Migraines may be mini-strokes that cause brain damage

A migraine is an episodic, intense and debilitating headache characterized by severe pain on one or both sides of the head, which is often accompanied by nausea or vomiting.The condition is very common, affecting 1 in 4 women and 1 in 12 men (that is, between 12-28% of the population), but its cause remains unknown. One theory is that migraines are caused by rapid constriction and dilation of the blood vessels in the brain. Another hypothesis is that migraine is caused by cortical spreading depression (CSD), a wave of nerve cell inhibition that propagates itself across neural tissue; CSD has also been implicated in stroke and other types of brain trauma.

A new study by researchers form the Department of Neurosurgery at the University of Rochester Medical Center in New York, published online in Nature Neuroscience, shows that the damage to neural tissue that occurs during a migraine episode is exactly the same as the damage that occurs in a transient ischaemic attack, a minor stroke in which blood flow to parts of the brain is temporarily interrupted. The study povides evidence that migraines act like transient mini-strokes – they starve parts of the brain of oxygen, leading eventually to damage of those parts.

Maiken Nedergaard and her colleagues induced CSD in mice, and used a combination of state-of-the-art imaging techniques to observe, at cellular resolution, the metabolic and structural changes that occur in neurons during the migraines. They found that CSD is associated with depleted levels of oxygen (hypoxia) in brain tissue. This hypoxia can occur even though there is no decrease in blood supply. This seemingly paradoxical situation arises because, during CSD, the consumption of oxygen exceeds the rate at which the gas can be supplied. It appears that the cells closest to capillaries consume the available oxygen, at the expense of cells further away.

It was also found that the wave of CSD caused a change in the structure of neurons in the affected areas of the brain. Strains of transgenic mice expressing yellow or green fluorescent protein were created, and two-photon fluorescence microscopy was then used to image the intact exposed brains of live the animals.

Looking at neurons in layer 2 of the cerebral cortex, the researchers found that, as the CSD wave front passed over the cells, neuronal cell bodies increased in volume, and the cells lost many of their dendritic spines. Cell bodies increased by almost 40%, but returned to their pre-CSD volume within 10 minutes. (Watch a film clip of this process here.) The breakdown in the structure of the dendritic trees occurred within seconds of the wave reaching the cells, but was also temporary. In some cases, it was very severe – 4 out of 10 mice lost an average of almost 80% of dendritic spines in cortical layer 2 cells.

In about 25% of migraine sufferers, the headache is preceded by visual disturbances called the aura. Nedergaard suggests that the aura could be a warning that some parts of the brain are being starved of oxygen. Treatment of migraine has usually focused to alleviating pain – sufferers often take non-steroidal anti-inflammatories such as aspirin or paracetomol – and it is estimated that less than 20% of migraine sufferers who need preventative treatment actually receive it. The new findings suggest that those who suffer from migraines should try to prevent their headaches altogether, to minimize the possibility of brain damage. In some people, migraines can be brought on by various triggers, such as bright lights or loud noises, physical or emotional stress, and various drugs, including alcohol and caffiene. Migraines could be prevented by avoiding those triggers – at least in people who know what those triggers are.

Reference:

Takano, T., et al. (2007). Cortical spreading depression causes and coincides with tissue hypoxia. Nat. Neurosci. doi: 10.1038/nn1902. [Abstract]

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18 thoughts on “Migraines may be mini-strokes that cause brain damage

  1. I too was wondering about what Abi mentioned – unless if one is a chronic sufferer of migraine-induced brain damage, one is dumber by middle age and has less cognitive capacity to lose in old age? (I can say that with impunity because I have chronic migraines myself. They began in grad school, which is also when I started to feel really stupid and inept – coincidence? I think not!).

    I also wonder about another recent study – the correlation of migraines in youth with mental illness/suicide. Both that study and the study Abi mentioned found the strongest results with the subject cohort that has “migraine with aura.” I’m beginning to wonder if “migraine with aura” has a different etiology than non-aura migraine, because that group always seems to segregate with the most extreme results – not the people with the most migraines, or the people with the most painful ones, but the people with aura.

  2. This will definitely make me considering using the ‘every day’ preventative drugs rather than Imitrex. Then again, I have a feeling that my migraine rate will diminish dramatically when I’m done with grad school.

  3. Those numbers are really high. And “Migraines could be prevented by avoiding those triggers – at least in people who know what those triggers are.”

    Is this an automatic physiological reaction we have 0 control over? what conditions allow a trigger cause the migraine automatically? can we stop the initial “encoding” of the trigger?

  4. As someone who actually suffered a very extreme hemiplegic migraine 3 years ago and was left with all the sx of stroke damage, I thoroughly resent this story being illustrated with a posed woman with a headache.

    I have always said that my condition is only 5% headache (and sometimes not at all). The other sx are FAR more devastating.

    After nearly 3 years I am finally seeing a neurologist in 2 weeks time. I live in the UK where the National Health Service is virtually bankrupt – they will do anything to fob you off so that they don’t have to treat you.

    Despite countless visits to my GP AND privately paid for tests which evidence the brain damage, I have been completely ignored and fobbed off. I have not been able to work for 3 years, I now face losing my home. And this is entirely due to medical negligence – and yes, litigation is now in initial disclosure stages.

    PLEASE STOP confusing migraine with ‘bad headache’ – it is absolutely not. It is a serious and very debilitating neurological condition. This research only confirms what I and many other HM sufferers have been saying to the arrogant know-all b’stard medics for years.

  5. Hmm. What if you only get the aura? I haven’t had a full migraine in a while (and none have managed to top the first one, during which I was vomiting so badly that the school nurse was worried that I had meningitus!), but I still occasionally get the aura. Often if I make an effort to ignore it, it goes away…

  6. My migraines began many years ago in my late 20s when I had to take an eye exam before being allowed to work with lasers in the lab. They flash a very bright light in your eye and as I recall they do that in order to take pictures of your retina. By the time the eye exam was over I had a migraine that lasted 3 days and eventually required a shot of a new drug the doctor at the university health clinic was unfamiliar with back then – imitrex. The pain subsided completely within 5 minutes but frightening side effects occurred. I had an imitrex prescription (pills) after that but I feared taking it as the cure might be more dangerous than the disease. But these days I have maxalt, which doesn’t have the side effects and I’m less afraid to take it. Still, I’m not surprised if migraines cause damage because it seems like anything that painful must. I’ve also been left with inflamed nerves in my scalp after migraines, weird as that sounds.

    Anyway, you mentioned that the observed changes in the cells were temporary, but later you noted that perhaps people with migraines should try to prevent them to minimize the possibility of brain damage. I’m all for preventing them, of course, but was there some indication in this research that some changes would be permanent?

  7. This is all well and good, but the drugs to treat migraine have many damaging side-effects. some just now being discovered or admitted. Just read a recent article about a man who now suffers from disc damage in his back…after long term Imitrex use. The PDR (physicians desk reference) alludes to this side effect! I have neck and shoulder pain that I can not attribute to anything else, used Imitrex for years until it started giving me rebound headaches. Not to mention heart damage. If you think Maxalt has no side effects, think again. This drug uses the same chemicals as Imitrex. They are all in the Triptan family. Maybe you just don’t feel the same way after taking it, but it is dangerous stuff. Can damage heart as well.
    THEN, the stuff they want to put us on for preventative is equally as dangerous.
    Sorry, not for me. I am trying supplements to help change serotonin levels, melatonin, etc.
    I don’t want to turn 60 and not be able to go up a flight of stairs as the triptans have damaged my heart, or be stuck on a dangerous anti-depressant for the rest of my life.
    Avoiding triggers is best idea, but some of us the triggers elude us. Have your neorutransmitters tested (go to a naturopathic dr. for help with this) and start taking the supplements to change your overages and/or shortages!
    ALL of these DRUGS Drs. want to push on us are useless and dangerous.
    I don’t trust this research either. In the end some BIG PHARMA just wants to put us on another useless drug…next we’ll hear about a preventative for brain damage if you are a migraine sufferer…good ol’ scare tactics!
    Don’t use goodbrainahealthkiller if you breathe air, sleep more than 3 hours a day or consume fruits and vegatables. Side effects are generally moderate and include…
    Sorry, the BIG PHARMA stuff is NOT the way to go. Just adds more damage to the formula.
    Good luck fellow migrainers.
    Probably a lot of these headahces have to do with all the garbage that is in our food, air and envirnoment. Let’s see a move to remove a lot of these dangerous colorings and preservatives from our food and I’ll bet the number of migraine sufferers would go down also.

  8. I have just recently been diagnosed with Dolichoetasia which is unfortunately “rare” so I can’t find out much about except that it is an abnormality in my head and has some correlation with strokes. I think my migraines and headaches and recent dizziness are all related. I believe that my migraines have been some kind of mini strokes which have caused damage which is now causing the dizziness. Any one else experiencing this?

  9. Someone I know has been put on oxygen for his fibrotic lung disease.
    I tried it when I started getting on of my multi symptom, aura impending migraines. Worked like a charm. I have been completely debilitated by my migraines, and am thrilled to find a successful treatment. As I am breaking the law, I plan to go to my Dr. to explain the successful treatment, and get a proper RX.

  10. I think anyone who has experienced repeated migraine aura episodes (with or without a headache afterwards) must suspect that something was getting damaged in the brain. Like Debra above, I think that years of migraine aura may have caused a real neurological problem — in my case, it might have been the trigger that led to my now having Parkinson’s disease. Of course, everyone with PD is trying to figure out how he or she got it, but I do wonder about this. So many doctors, on hearing that a patient “has migraines” seem to dismiss this as something relatively minor and an indication that the patient may be slightly neurotic.

    In some of the studies I’ve seen, there appears to be a link between migraine aura and platelet clumping or aggragation. Some doctors recommend medications that prevent this from happening. I had a damaged mitral valve as a child, which caused blood turbulence, which, in turn, may have caused platelets to clump. I began having migraine aura as a teenager. After valve surgery in 1981, I had a dramatic increase in the aura episodes — sometimes many in one day. Since I was taking warfarin — to prevent a stroke from a blood clot caused by the turbulance from the artificial heart valve — my cardiologist was not concerned. I still take warfarin and now also aspirin because, in addition to the migraine aura, I had TIAs — times when I’d go blind in one eye for several minutes.

    So, it seems as if the heart valve that saved my life may have contributed to migraine aura, which may have triggered Parkinson’s. I guess it was an okay trade, but I’d love to know that my idea is correct.

  11. Migraines started in 6th grade.been taking midrin since 1980. It almost always works.I had a mild stoke they think.I only have trouble swallowing and with speech and I lose my voice sometimes. the new neurologist doesn’t think the speech and swallowing problems are from a stroke because they happened gradually over a year.Obviously i am having neurological problems.A neurosurgeon is redoing all my tests since sometime over the past year I developed aneurysms behind both eyes. I wonder if the migraines have anything to do with all this. Anyone ever heard of anything like this? I haven’t. there is parkinsons and ms in my family also. I have no other symptoms of a stroke and the aneurysms are very small so the don’t want to do any thing with them at this time.I took naproxen for 3 years every day for a rotater cuff injury so it may have done this.I am very frustrated that after a year I am worse and still have no explanation of why any of this happened.

  12. I started getting “auras” at age 48 without any accompanying headache – probably 2 – 3 times a year. Havn’t noticed any neurological deficits yet, but obviously doesn’t mean they aren’t accrueing. This is indeed a disturbing association.

  13. I wouldn’t believe anything that Merck says..to be honest. I’ve read a lot of articles that said that migraines with aura cause more damage. Merck is the only source that has opposed that.

  14. Just for the record, I might as well add my own experience. It’s more of the same:

    Migraines started in my mid teens, I’m now 65. I was told once by an authority in the field that I had one of the worst migraine cases in the country (Canada), if not North America. His name was John Edmeads from Toronto’s Sunnybrooke Hospital.

    From 1980 to 1995 I went through suicidal pain, daily. And all the silly meds they could throw at me. Imitrex injections were introduced to the tune of about twice a day. They more or less gave me my life back.

    Introversion, failed career, altered personality, depression, failed marriage, etc. Recently Maxalt came on the scene and at least lowered the enormous expense, but the migraines are still there. Recently am experiencing trembling, maximum dose anti-depressants, major short term memory loss, etc.

    Neurological symptoms are beyond my layman’s comprehension, it’s enough to say that my whole life is tuned to instinctively avoiding triggers, accepting the trembling, coping with living alone without the ready ability to remember details that most people take for granted.

    Brain damage? I think so. Shortened life span? No doubt. Hope? None.

  15. I have had migraines since I was a teenager, one in 1999 caused my blood pressure to drop so much I thought I was dying, but most of them are nothing more than a interruption of my life. Last week I had one that had a different aura, it was in the middle of my right field of vision, most of the auras I get are in the outer left vision area. The next day I was very slow and I felt as though I’d had a stroke, I looked this website up just to see if there were others who felt these symptoms, I was surprised to see how much info there is on here, mostly I was hoping not to confirm that I might have gotten some brain damage from a migraine, so much for that theory.

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