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Viagra and similar preparations and migraine
Viagra is not the only preparation that triggers migraine in some migraineurs - other similar drugs that strengthen an erection have the same unpleasant side-effect. An expert recommends that men who have experienced migraine in the hours after using Viagra or equivalent drugs (like Levitra and Cialis) should have a triptan ready against migraine. There are as yet no medical studies of the effect of taking triptans before the potency pill if it triggers migraine.C. Kruuse, 2004. Expert commentary on Phosphodiesterase-5 inhibitors and migraine. Headache 44, 925-926.
What happens in the body during a migraine attack?
During symptoms of aura, there is a fall in blood flow through the parts of the cerebral cortex where the aura symptoms are generated. If you have aura, some time after the symptoms of aura disappear and the headache has started, the blood flow becomes normal and sometimes increases a little before becoming normal. These changes in the blood flow through the brain are entirely independent of the headache. The flow of blood is normal during the whole of a migraine attack without aura.During a migraine headache, the large arteries in the brain together with the temporal lobe artery enlarge 9% on the side of the brain where the headache is felt compared to the pain-free side.
During migraine attacks both with and without aura, there is special activity in the brain stem. What this means has not yet been explained, but it may be some kind of ´migraine generator´.
During a migraine attack, there are increased concentrations of serotonin and calcitonin-gen-related peptide, CGRP, in the brain. Migraine patients are more sensitive to nitrogen oxide (NO) than healthy people. NO can trigger attacks in migraine patients. This makes it possible to study disease mechanisms in more detail.
From the Institute for Rationel Pharmaco-therapy, November 2004 http://www.irf.dk/dk/publikationer/rationel_farmakoterapi/maanedsblad/2004/migraene
Stress causes migraine or migraine casues stress?
A French study has shown that 141 migraineurs who had on average 3.4 attacks per month were more stressed than a control group who didn´t have migraine. The scientists concluded that migraine is caused by stress, but there was nothing in the study that documented that the opposite conclusion wasn´t just as valid, - that migraineurs are more stressed simply because they have migraine and therefore have less time and energy available than healthy people.C. Wacogne, J. P. Lacoste, E. Guillibert, F. C. Hugues og C. Le Jeunne, 2003. Stress, anxiety, depression and migraine. Cephalalgia 23, 451-455.
Three theories about migraine
During recent years, three different theories about what happens in the brain during a migraine attack have been developed.The main points of the three theories are:
• migraine is caused by the enlargement of blood vessels in the brain and around the skull; pain arises because of the changes in the blood-vessels
• migraine is caused by abnormal nerve activity in the brain (spreading cortical depression); the activity spreads through the brain cortex and gives rise to aura and later pain
• migraine is caused by a sterile inflammation bin the sheaths around the dura mater; the sheaths become sensitive and painful; phosphorus and nitrous oxide (NO) increase the sensitivity.
It´s not yet possible to determine which one or whether more than one of the theories is correct, but all of the three theories can explain why many migraineurs get relief from treatment with triptans.
K. W. Johnson, L. A. Phebus and M. L. Cohen 1998. Progress in Drug Research 51: 219-44.
Uploaded 14-12-2004
Stomach-ulcer bacteria can cause migraine
Two independent studies have shown that migraineurs have bacteria of the species Helicobacter pylori more commonly in their stomach than non-migraineurs. When the bacteria were removed using antibiotics, 23% of 225 patients became free of migraine, while 75% had noticeably reduced migraine a whole year after treatment.Reuters 10. September 1998.
Uploaded 14-12-2004
Sinus-migraine – an overlooked problem?
There may be many people who get migraine because they have something wrong in their nose. This type of migraine is often difficult to treat with medicine and the nose problems are often overlooked by doctors. Some reports from recent research nonetheless shows that help can be obtained, either by correcting the internal shape of the nose or by removing snot and slime.A study of 19 patients with migraine that didn´t respond to treatment with the normal medicines showed that 15 of them became free of migraine after an operation to alter the passage in the nose (1). A 65-year old woman whose nose was blocked had so many migraine attacks that she developed a serious misuse of ergotamine. When the slime in her nose was removed, the migraine attacks disappeared entirely during 3 weeks (2). 15 migraineurs received operations that gave them enlarged passages through the nose. 6 of the patients became entirely free of migraine attacks and 5 had significant improvements. Migraine attacks continued without change in 4 of them (3).
In Switzerland it has long been recognised that migraine has ´something to do with your nose´. Between 1973 and 1991, 299 patients with different types of migraine received operations that ´corrected´ the nose after which 79% were completely free of their headaches or migraine. A further 12% still had some pressure in their head but no attacks while only 11% continued to have mild attacks of migraine or headache (4).
Americans, too, have noticed ´something to do with the nose´ for a long time. As long ago as 1988, scientists from Johns Hopkins Medical Institution showed that the anatomical shape in the nose or simply too much snot can lead to migraine that is difficult to treat medically (5).
The Danish Migraine Association has no information whether or not Danish migraineurs have been cured of their attacks in this way.
(1) D. M. Clerico, K. Evan, L. Montgomery, D. C. Lanza and D. Grabo, 1997. Endoscopic sinonasal surgery in the management of primary headaches. Rhinology 35, 98-102.
(2) B. Bauer, S. Evers, H. W. Lindorfer, G. Schuierer, H. Henningsen and I. W. Husstedt, 1997. Headache caused by a sphenoid mucocele but presenting as an ergotamine-induced headache. Headache 37, 460-2.
(3) A. Welge-Lussen, R. Hauser and R. Probst, 1996. 3-year follow-up after endonasal microscopic paranasal sinus surgery in migraine and cluster headache. Laryngorhinootologie 75, 392-6.
(4) V. J. Novak and M. Makek, 1992. Pathogenesis and surgical treatment of migraine and neurovascular headaches with rhinogenic trigger. Head Neck 14, 467-72.
(5) D. W. Kennedy and M. C. Loury, 1988. Nasal and sinus pain: current diagnosis and treatment. Semin Neurol 8, 303-14.
Uploaded 14-12-2004
Biogenic amines - their absorption and excretion
Research on rats has shown that tyramine is absorbed in the small intestine (1)- especially in its upper parts, the duodenum and jejunum. It therefore takes a couple of hours or more after you have eaten something containing tyramine for a migraine attack to start.A new study using rats has shown that tyramine is broken down by the enzyme MAO-A (2). But was known as long ago as 1970 that tyramine gets broken down in the liver and that it takes longer when the blood contains large amounts of estradiol (an estrogen) (3).
Phenylethylamine is absorbed in the duodenum and is excreted through the kidneys (4). In 1974 a paper in Nature (5) reported that, at least some migraineurs lack the enzyme MAO-B which breaks down phenylethylamine, which is found in chocolate and other foods. Migraineurs had less MAO-B in their blood than the control group, both while they had migraine and in the periods between attacks. The study also showed that it was possible to provoke a migraine attack with 3 mg phenylethylamine or 100 mg tyramine.
(1) T. Kimura, N. Iwasaki, J. I. Yokoe, S. Haruta, Y. Yokoo, K. I. Ogawara and K. Higaki, 2000. Analysis and prediction of absorption profile including hepatic first-pass metabolism of N- methyltyramine, a potent stimulant of gastrin release present in beer, after oral ingestion in rats by gastrointestinal-transit-absorption model. Drug Metab. Dispos. 28, 577-81.
(2) M. Valoti, J. A. Moron, A. Benocci, G. Sgaragli and M. Unzeta, 1998. Evidence of a coupled mechanism between monoamine oxidase and peroxidase in the metabolism of tyramine by rat intestinal mitochondria. Biochem Pharmacol.55, 37-43.
(3) G. G. S. Collins, J. Pryse-Davies, M. Sandler and J. Southgate, 1970. Effect of pre-treatment with østradiol, progesterone and DOPA on monoamine oxidase activity in the rat. Nature 226, 642 -643.
(4) F. Gonzalez-Sastre, J. Mora, R. Guillamat, J. M. Queralto, E. Alvarez, C. Udina and J. Massana, 1988. Urinary phenylacetic acid excretion in depressive patients. Acta Psychiatrica Scandinavica 78, 208-210.
(5) M. Sandler, M. B. H. Youdim and E. Harrington, 1974. A phenylethylamine oxidising defect in migraine. Nature 250, 335-337.
Uploaded 14-12-2004
Blood platelets can possibly explain chronic headache
Some migraineurs take large numbers of pain-killers without much effect. Instead, they get chronic headache from the large consumption of medicine. These over-users have blood platelets with more vacuoles (liquid-filled spaces) in comparison to a control group consisting of migraineurs with a more moderate intake of pain-killers. The large ingestion of painkillers causes the blood platelets to release increased amounts of 5-HT, so there isn´t so much 5-HT left in the blood platelets. During an attack, migraineurs have correspondingly large vacuoles, but at the same time have a larger number of vacuoles with 5-HT in their blood platelets.A. Srikiatkhachorn, S. Maneesri, P. Govitraong and V. Kasantikul, 1998. Derangement of Serotonin System in Migrainous Patients With Analgesic Abuse Headache: Clues from Platelets. Headache 38, p. 43-49.
If you have chronic headache because of a large intake of painkillers, there´s probably only one way out: Talk to your doctor about giving up the painkillers and wait until your body’s blood platelets have renewed themselves. That takes time!
Årsager til migræne NO content is elevated in the blood of migraineurs A study of 100 migraineurs and an equivalent number of control persons has shown that migraineurs have a higher content of NO (the active part of nitro-glycerine) in their blood when they have an attack regardless of whether or not they have aura. The authors suggest that NO frees CGRP, which increases the size of blood vessels and enables a so-called inflammation, i.e. a leakage of small amounts of blood plasma the walls of the blood vessel causing pressure on the membrane surrounding the brain, so we experience a migraine attack.
D. D´Amic, A. Ferraris, M. Leone, A. Catania, A. Carlin, L. Grazzi og G. Bussone, 2002: Increased plasma nitrites in migraine. Cephalalgia 22, 33-36.
Uploaded 14-12-2004
CGRP - news from Danish migraine research!
CGRP (1) is a chemical that has been studied for a long time by Danish migraine researchers. Migraineurs have a permanently higher content of CGRP in their blood and a substantially higher content during an attack. More knowledge about the chemical and our reactions to it may possibly lead to better treatments.If the chemical is injected into non-migraineurs, they don´t suffer a migraine attack, but a study at the Neurological Department of Glostrup Hospital in Denmark has shown that injecting migraineurs with CGRP causes a nearly ´normal´ migraine attack without aura in 8 out of 9 trial subjects. A light headache started immediately after CGRP was injected and a nearly ´normal´ migraine started a few hours later (5 hours on average). Only one out of nine of the same patients reacted with a migraine attack when they were injected with a placebo.
CGRP is a powerful chemical known to expand blood vessels everywhere in the body. For this reason, the studied subjects also showed reduced blood pressure immediately after administration of CGRP and their heart rate increased, too. Administration of a placebo had no effect on their blood pressure and heart rate. Finally, the subjects´ faces and breasts felt warm immediately after administration of CGRP, but not after treatment with a placebo.
The researchers are now speculating about the relationship between NO (nitro-glycerine) and CGRP and are also wondering why there is a delay of several hours before the migraine attack starts.
L.H. Lassen, P. A. Haderslev, V. B. Jacobsen, H. K. Iversen, B. Sperling and J. Olesen, 2002. CGRP may play a causative role in migraine. Cephalalgia 22, 54 - 61.
(1) CGRP stands for Calcitonin Gene-Related Peptide
To top Uploaded 14-12-2004
Bacteria make biogenic amines - and as a result we get migraine
In 2001 the Danish Migraine Association took part in a conference together with Europe´s leading experts on biogenic amines - the chemicals that give food migraine to up to 5% of all adults and children.The scientists were united in agreeing that the two biogenic amines, tyramine and phenylethylamine, are created nearly exclusively by the bacteria that break down the amino acids in our food. Good hygiene in the food industry and in the kitchen are the best way for migraineurs who have food migraine. Many of our foods are produced with the help of bacteria. All of the products that we think of as ´ripened´ or ´fermented´ have been treated by bacteria. But a long list of other products which we wouldn´t normally think of as being ´ripened´ and in fact also the result of treatment with bacteria. Bacteria create pleasant tastes or have been present from an early stage in the production of the food or drink and are removed at a later stage, but their products tyramine (TYR) and phenylethylamine (PEA) remain.
These two chemicals are not broken down by boiling (regardless of how long it lasts). So generally there is no possibility of removing them once they are present in our food.
The bacteria that produce the two chemicals are first and foremost in the groups Lactobacter and Enterococcus. Lactobacteri and similar species are commonly used to make ´industrial´ foods and Enterococcus bacteria are found in our digestive tracts, but not a lot is known about how their lives inside us affect us. That´s one of the themes that scientists consider taking up in the coming years.
Luckily industry is to some extent aware of the problem and some products are now produced using starter cultures of bacteria that don´t produce tyramine, phenylethylamine or histamine (also a product of bacteria).
We still have no possibility of requiring that foods be marked to show whether they have been produced in a satisfactory way, i.e. from fresh ingredients and with the use of bacterial cultures that don´t make biogenic amines. As migraineurs, we cannot therefore see from the goods whether or not they are suitable for us or whether they are made in a way that gives us migraine.
There´s only one sure way of avoiding biogenic amines - by buying fresh produce, keeping them in the fridge and generally avoiding everything that has been made with the help of bacterial cultures. But that´s not easy in today´s world. Really many foods contain one or more ingredients made with the help of bacteria. Soya protein and citrus concentrate are in nearly all industrially-produced foods, because soya protein gives a good consistence and citrus concentrate works as an antioxidant and tastes ´fresh´.
For the moment, we can only appeal to industry to use ´migraine friendly´ bacteria and push to get declarations on bacterial cultures so that only the ones that don´t produce biogenic amines are preferred. But that´s not a concession we´re going to get in the near future.
Foods that contain more than 2% salt are generally not subjected to treatment by bacteria so are generally safe. Unfortunately, modern developments are for consumers to want less salt in their food. A high salt content in the final product is no guarantee - bacteria can have been used before the salt was introduced. In the meantime, we have just to learn the bacterially-produced products whenever possible.
Foods which food migraineurs are wise to avoid...
Uploaded14-12-2004
Blood pressure and migraine
We often hear migraineurs say that they have had high blood pressure, that is has now been corrected and that their migraine had subsided at the same time.A survey of 1174 participants from Brazil (1) showed that there was no difference in the occurrence of migraine between those that had normal blood pressure and those with high blood pressure.
In Britain, 1000 women were examined for menopausal problems (2). Those who had a high diastolic pressure (the low number) had less migraine than the rest of the group.
Norwegians, too, were asked (3). 22685 adult Norwegians had their blood pressure measured in 1985 and were asked about their migraine 11 years later. There was no connection between blood pressure and migraine.
Researchers in the US looked at migraineurs who were so severely influenced by their migraine that they could not function (4). The diastolic pressure (the low number) of the most severely affected among 80 migraine patients was higher than that of the less severely affected and of the control group of 85 matching people.
So until we know more, doctors may not be all that sure that high blood pressure can cause migraine.
(1) M. Wiehe, S. C. Fuchs, L. B. Moreira, R. S. Moraes and F. D. Fuchs, 2002. Migraine is more frequent in individuals with optimal and normal blood pressure: a population-based study. J Hypertens. 20,1303-6.
(2) J. Hodson, J. Thompson and F. al-Azzawi, 2000. Headache at menopause and in hormone replacement therapy users. Climacteric. 3, 119-24. (3) K. Hagen, L. J. Stovner, L. Vatten, J. Holmen, J. A. Zwart and G. Bovim, 2002. Blood pressure and risk of headache: a prospective study of 22 685 adults in Norway. J Neurol Neurosurg Psychiatry;72, 431.
(4) A. Shechter, W. F. Stewart, S. D. Silberstein and R. B. Lipton. 2002. Migraine and autonomic nervous system function: a population-based, case-control study. Neurology 58, 422-7.
Uploaded 02-03-2005
Histamine influences some of the arteries in the brain
Researchers in Glostrup, Denmark, have wondered for a long time why some arteries in the brain change their diameter during a migraine attack, while others don´t. They injected histamine into test persons with migraine without aura at a time when they did not have migraine, and measureD the diameter of the arteries in their brains and arms.The temporal artery expanded significantly more than the arteries in the arm after the histamine injection.
L. H. Lassen, I. Christiansen, H. K. Iversen, I. Jansen-Olesen and J. Olesen, 2003. The effect of nitric oxide synthase inhibition on histamine induced headache and arterial dilation in migraineurs. Cephalalgia 23, 877-886.
Uploaded 14-12-2004
Stress and migraine - few studies confirm the connection
Stress is the triggering factor for migraine that is most often quoted. Nonetheless, after a search of the literature about stress and migraine, Galiano et al. conclude that there are very few studies about the connection between stress and migraine.Rev. Neurol. 1995, 23 830-32.
Uploaded 03-03-2005
Stress and migraine lack any physiological connection
We often hear that stress causes migraine. But the term 'stress' is only poorly defined. One definition is that there is no connection between the desire experienced and the resources available to achieve it – in other words, more is required of us than we can deliver. Stress can be caused either by real external pressure or by something we impose on ourselves.It is well-documented that we produce the chemical ß-endorphine when we feel stressed. Among other things, this chemical makes us feel pain less. At the same time, the brain releases cortisone that strengthens the heart beat more strongly. So stress makes us ready to fight!
Stress may 1) trigger migraine in disposed people, 2) increase the pain felt if one already has migraine, 3) trigger a migraine attack, 4) make us feel that an attack is worse than it already is, or 5) migraine may make us feel stressed so making us feel even worse than we do.
The problem is that none of the 5 possibilities can be supported physiologically and no study has ever shown any of these connections write two American doctors.
J. M. Nash and R. W. Thebarge, 2007. Understanding psychological stress, its biological processes and impact on primary headache. Headache 46, 1377-1386.
Uploaded 28-8-2008.
Nitric acid provokes migraine
A goldsmith iscovered that he got migraine when he used nitric acid (HNO3) to polish copper and brass. Nitric acid releases NO and NO2. When the goldsmith went on holiday or for some other reason didn´t use nitric acid to polish with, he had only a few migraines. The nitric acid attacks lasted 12 - 24 hours and could be treated with triptans.M. Granata,C. Ammendoela, M. Nicoletti, P. Martelletti and M. Giacovasso, 2004. Headache induced by accidental nitric acid inhalation. Cephalalgia 24, 238.
Uploaded 30-10-2005
Coffee does not provoke migraine (in Norway)
1,741 inhabitants of the town of Vågå in north Norway were asked about their migraine and their use of coffee. On average they drank 4.7 cups of coffee per day - the men a little more, the women a little less. Even among those who drank a lot (over 10 cups per day) or who drank amounts that varied considerably from time to time there was no sign of an increased tendency to suffer from migaine. Two inhabitants of Vågå who drank lots of coffee had headaches in the morning and at weekends, but their headaches weren´t pulsating nor was their nausea connected with the headaches.O. Sjaastad and L. S. Bakketeig, 2004. Caffeine-withdrawal headache. The Vågå study of headache epidemiology. Cephalalgia 24, 241 - 249.
Uploaded 30-10-2005
Biogene amines in fish and soy sauces
The content of biogene amines in food is an indication of how much they have rotted or decomposed. High concentrations of biogene amines can cause food poisoning. In much lower concentrations they can trigger migraine attacks in some migraineurs.Biogene amines form when amino acids in food are broken down by the help of enzymes that are already found in plants, animals and micro-organisms. Biogene amine content is highest in matured or fermented foods such as anchovies, wine, beer and some cheeses and salamis. High concentrations can also be found in fish and fish-products that have not been kept at the highest hygienic quality.
A study analysed 45 commercial fish sauces and 23 soy sauces for their biogene amine content. The content of biogene amines in fish sauces varied substantially, from 100 mg/kg to 4000 mg/kg, depending on the method of manufacture. The content of biogene amines in soy sauces was different from and generally much lower than in fish sauces. The dominant biogene amine in soy sauce was found to be tyramine while the content of biogene amines in fish sauces was more varied, consisting of high concentrations of tyramine, histamine, tryptamine and others. The levels of biogene amines in fish sauces were at a level equivalent to that found in other matured foods like matured cheese.
R. Stute, K. Petridis, H. Steinhart and G. Biernoth, 2002. Biogenic amines in fish and soy sauces Eur Food Res Technol 215, 101–107.
Uploaded 28-8-2008.
Do biogene amines in ordinary vegetables constitute a risk?
Higher than normal contents of biogene amines (BA) in food are of interest for various reasons. For instance, histamine and tyramine are known to damage blood vessels and can have psychological effects, including triggering migraine. Higher than normal concentrations of BA are found in matured or fermented foods such as cheese, salami, saurkraut, wine and beer (1).The content of BA in non-matured foods is not so well-known. Czech scientists therefore examined how much BA is found in some commonly-used products such as chopped spinach, frozen green peas, tomato concentrate and ketchup (2).
The limit of detectability of histamine was 2.1 mg/kg and of tyramine 3.5 mg/kg. Because of this, the list in Table 1 shows significantly more products containing tyramine than histamine. None the less, the results show that all products have a relatively high content of tyramine, and ketchup had the highest. The content of histamine was generally low (see Table 2).
Table 1: Percentage of vegetables over the detectability limit of histamine or tyramine.
| Chopped, frozen spinach | Frozen green peas | Tomato concentrate | Ketchup | |
| Histamine | 25 | 14 | 26 | 38 |
| Tyramine | 53 | 86 | 74 | 83 |
Table 2: Average amine content (mg/kg) in those vegetables above the detectability limit for histamine or tyramine.
| Chopped, frozen spinach | Frozen green peas | Tomato concentrate | Ketchup | |
| Histamine | 3.4 | 3.1 | 4.6 | 6.5 |
| Tyramine | 10.2 | 8.7 | 10.4 | 33.6 |
The scientists concluded that the content of BA in the vegetables they had studied does not constitute a health risk for healthy people. None the less, people being treated with MAO-agonists (anti-depression drugs) should avoid foods containing tyramine as they can provoke a serious increase in blood pressure. Should this happen, it needs to be treated rapidly, e.g. by the emergency department of a hospital.
Whether or not migraineurs can be considered healthy, or whether the tyramine content in spinach, green peas and ketchup can be a problem for them was not discussed in this study. However, older studies have shown that disposed people can have a migraine attack if they drink water containing as little as 1 mg of tyramine chloride (3).
(1) P. Videbech, consultant, specialist in psychiatry (Last updated 04-04-2005) MAO-hæmmere. Netdoktor.dk (Danish netdoctor web site) – Depression & Anxiety. Based on an original paper by Marianne Møller, pharmacist.
(2) P. Kalac, S. Svecova and T. Pelikanova (2002) Levels of biogenic amines in typical vegetable products. Food Chemistry 77, s. 349–351.
(3) F. C. Strong III, 2000. Why do some dietary migraine patients claim they get headaches from placebos? Clin Exp Allergy 30, 739-43.
Uploaded 28-8-2008
Flashing light followed by an icepack on the forehead causes migraine
Migraineurs have enough problem with getting migraine from having an icepack applied to their frontal artery, but the pain is worse if they are first exposed to flashing light. Migraineurs also experience nausea at the same time as their headache.Non-migraineurs don´t react at all, with migraine or anything other comparable pain, after being treated with ice.
P. D. Drummond and A. Granston. 2005. Painful stimulation of the temple induces nausea, headache and extracranial vasodilation in migraine sufferers. Cephalalgia 25, 16-22.
Uploaded 6-4-2006
Cervicogen migraine — comes from the neck
Cervicogen migraine — or migraine that originates in bone or muscle tissues in the neck and throat – is often the cause of migraine that is difficult to treat. The attacks happen if, for example, you make a wrong movement of the head, or if the throat is compressed (e.g. by pushing your head against the headboard when asleep in bed). Only between 0.4 and 2.5% of all adults suffer from cervicogen migraine, but 1 in 5 of chronic migraineurs who request treatment have this type of migraine.A scanning will rarely show anything wrong so cervicogen migraine is difficult to diagnose.
Treatment with triptans normally don´t work but a combination of muscle-relaxing medicine, treatment by a physiotherapist or chiropractor, NSAIDs or biofeedback may be worth trying.
D. M. Biondi, 2005. Cervicogenic Headache: A Review of Diagnostic and Treatment Strategies. Journal of the American Osteopathic Association 105, suppl 4, 16-22.
Uploaded 21-10-2006
Light nights can give more migraine attacks
A team of doctors advertised in northern Norway for migraineurs. 169 people responded, 98 with and 71 without aura.The migraineurs were asked whether they thought they had more attacks at certain times, and 47% of those who had aura answered that they usually had more attacks in summer. 17% of migraineurs without aura also thought that they had more attacks in summer. Those with aura also answered that they were generally affected by strong or flickering light, even when they were not having an attack.
The doctors now speculate about whether it is the light itself or a biologic rhythm that makes this difference between summer and winter in migraineurs with aura.
K. B. Alstadhaug, R. Salvesen and S. I. Bekkelund, 2005. Seasonal variation in migraine. Cephalalgia 25, 811-816.
Uploaded 21-10-2006
Mast cells and migraine – yet another theory
Mast cells are particullarly active in someone with an allergy or asthma. Mast cells are found especially around inflamed places. A group of Greek scientists have therefore put forward the hypothesis that migraine is caused by increased activity of mast cells in the brain.Mast cells have many functions. They release chemicals such as NO that expand blood vessels if they are exposed to CGRP (a chemical that triggers migraine). Mast cells are found in the tissues between the blood vessels so they stay fairly fixed. The type found in the brain is thought to control the permeability of the walls of the blood vessels – how much liquid can seep out from the blood vessel into the surrounding tissues. If the mast cells are subjected to stress, the amount seeping out increases. The scientists think that a number of drugs used prophylactically against migraine work because this type of medicine reduces the effect of the mast cells.
Mast cells also participate in healing wounds and defending against infections.
T. C. Theoharides, J. Donelan, K. Kandere-Grzybowska ana A. Konstantinidou, 2005. The role of mast cells in migraine pathophysiology. Brain Res Rev. 49, 65-76.
Uploaded 21-10-2006
Triggers - the list gets even bigger
Many doctors have formerly claimed that it is impossible to identify migraine triggers. Now other voices are being heard. For example the City of London Migraine Clinic has published a list of what they think triggers migraine (see below) that is given to patients of the clinic.1. Hunger: fasting, delayed meals, too little food, only a snack, salad or sandwich.
2. Various foods: cheese, chocolate, alcohol (red and white wine, other kinds of alcohol), Chinese food, coffee, tea, other drinks.
3. Sleep: too much or too little sleep.
4. Female hormones: menstruation before, during or after menopause, contraceptive pills, pregnancy.
5. Pains in the head or neck: in the eyes, nose and sinuses, throat or jaw.
6. Surroundings: warm, cold, light, noise, cinema, shopping, parties and company, smells.
7. Exertion and travel.
8. Allergy.
9. Stress: before or after.
10. Smoking.
The most recent suggestion from the City of London Migraine Clinic for a trigger is lack of liquids. 36% of British migraineurs (96 people in all) thought they got migraine if they became dehydrated. The doctors remarked that migraineurs generally were very sure about what triggered their attacks and answered hesitantly when they were asked abouttriggers they hadn´t previously thought about.
J. N. Blau, 2005. Water deprivation: a new migraine precipitant. Headache 45, 757-759.
The Danish Migraine Association recommends eating fresh foods and being aware of alterations in your migraine pattern if you alter your intake of hormones.
Uploaded 21-10-2006
Oestrogen gives migraine to men who change sex
A study of a small group of Dutch men who took anti-androgen hormones during a sex-change procedure showed that 26% of these people developed migraine. That compares to 25% of women who have migraine, while only 7.5% of men have it. A half of those who went through the change of sex experienced sight disturbances (aura or the like) just before the migraine pain. Treatment with oestrogen stimulates the production of nitrogen oxide (NO) in blood vessels and NO is a known trigger for migraine.T. Pringsheim ano L. Gooren, 2004. Migraine prevalence in male to female transsexuals on hormone therapy. Neurology 63, 593-594.
These results suggest that oestrogen is the reason that 3 times as many women as men have migraine, but that men are genetically just as predisposed as women to get migraine.
Uploaded 21-10-2006
Weather again
77 migraine patients attending a clinic in Connecticut, USA recorded when they had migraine during 2 - 24 months in 1997-1999.Their migraine attacks were compared with what kinds of change in the weather there had been at the same times.
The patients thought generally that they had migraine because of the weather conditions and 61 of them could describe what weather pattern triggered their migraine. The most important factors were rain, sunshine, low presure, falling pressure, high humidity and high temperatures (more than 20% of the migraineurs indicated these to be triggers).
The weather was divided into 43 different types that were grouped into 3 main groups that were then matched with the migraine diaries. 39% of the 77 migraineurs had more attacks on days that fell into one of the three main types of weather and 12% had migraine more often than expected during two of the 3 types of weather. 27 migraineurs reacted more often than expected when the weather was of the same type for several days in a row. 11 reacted more often than expected during periods of changeable weather such as changes in air pressure or temperature compared with one or two days before. And 10 migraineurs reacted more often than expected to a change in air pressure compared to two days before or after their attack.
The scientists concluded that especially temperature and humidity can trigger migraine and that there were differences between men and women or between age groups.
Unfortunately, there was no information about how many attacks were used in the study.
P. B. Prince, A. Rapoport, F. D. Sceftell, S. J. Trepper and M. E. Bigal, 2004. The effect of weather in headache. Headache 44, 596-602.
The Danish Migraine Association comments: Changes in air pressure have in the past been suggested as a triggering factor for migraine. The more studies, the more factors in the weather may be related to migraine. The probability is large of finding a connection which doesn´t really exist if comparisons are made between events that vary relatively unpredictably (e.g. migraine attacks and types of weather). So perhaps there isn´t any real connection between weather and migraine, just statistical coincidences.
Uploaded 30-10-2005
Weekend migraine – weelll…
One of the 'well-known' facts about migraine is that we often have attacks at the weekend. Three Norwegian scientists looked at this 'fact'. They asked 84 women of fertile age to keep a migraine diary for 12 months. They recorded a total of 2,314 attacks and they found that the attacks were evenly spread throughout the week, apart from Sundays, when there were substantially fewer attacks.Nineteen of the participants were students, unemployed or worked shifts so had no clearly defined weekends. This group had no fewer attacks on Sundays than on other days, even though they had migraine just as often as the other women.
K. B. Alstadhaug, R. Salvesen and S. Bekkelund, 2007. Weekend migraine. Cephalagia 27, 343-346.
Uploaded 28-8-2008
Pool players develop migraine
203 players of pool in Singapore (83% men) were asked if they had migraine. Their average age was 23 and 21 and they said that they often experienced a migraine attack while they played pool. 11 of these had migraine before they started to play pool, but the other 10 started to have migraine attacks after they started to play. The more often they played, the more migraine they had.R. C. S. Seet, Y. H. Chan and E. C. H. Lim , 2007. Headaches amongst pool players. Headache 47, 270-274.
We have reported elsewhere that physically strenuous sport can cause migraine. The game of pool is similar to billiards and snooker in that a cue is used to strike one ball against other balls on a table, and thus requires little strenuous activity.
Uploaded 28-8-2008
You DON’T get migraine from the radio waves transmitted by your mobile telephone
Or rather, it can’t be shown that your mobile phones transmissions do trigger migraine. This is the conclusion of a study involving 17 people who felt discomfort in their heads after they had used their mobile phone for more than 15 minutes.The people in the study were subjected to high frequency radio waves, like those emitted by mobile telephones, while they sat for an hour in a room where there was no other stimulation. The people in the study did not know when they were subjected to radio waves and when they were not (as a control). Their pulse and blood pressure was measured and they were asked to describe any symptoms they might have.
The scientists could find no difference between the symptoms with and without the radio waves. However, the do point out that a mobile is close to the ear when being used and this might give some people migraine.
G. Oftedal, A. Straume, A. Johnsson and L. J. Stovner, 2007. Mobile phone headache: a double blind, sham-controlled provocation study. Cephalalgia 27, 447-455.
Uploaded 28-8-2008