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Lectures on the cluster headache
Foreword
The aim of this paper is to present a working hypothesis which seeks to explain the phenomenon of CR in every sense, with the sole idea of establishing mechanisms to combat this disease. The greater or lesser success of these methods can be applied directly to determine the reliability of the assumptions. As the author of this hypothesis is not anywhere near the knowledge or minimum qualifications required for membership of a document of this nature, it should be interpreted merely as a fun “pseudo-scientific document" and all events in the discharge must be considered under this perspective.
The facts and statements that are incorporated in this document are the result of years of careful reading of studies of many kinds. There is no documentation of the sources of such information or its reliability, have just been collected over the years in memory of the author, so absolutely no valid documents. However I urge the reader to accept without more generously in a first reading to get an overview of the working hypothesis, which is what matters, leaving for a second phase, the questioning of the information contained herein.
While seemingly existing documentation on the cluster headache is very extensive, in fact most of it is recurring. Known and classified the disease for decades, most reports are nothing but collections or synthesis of other existing reports. Most of the information in this text comes from psychiatric studies, particularly relating to anxiety, depression or stress, general studies on migraine with fibromyalgia syndrome or Dawn, and even issues such pilgrims as breeding animals or the study of their migration.
Mechanism of the crisis
Before we can hypothesize about the cause of the CR, we must discuss the mechanism by which the characteristic "crisis" or "attacks" of pain occur.
In general, there is a growing consensus that crises are essentially in the inflammation of the trigeminal nerve due to pressure of the cerebral arteries dilated on the nerve. The inflamed nerve contribute to the flow of blood, through the walls of an artery, with a substance called CGRP peptide (calcitonin gen-related peptide), and this peptide and other activate platelets and mast cells, producing a discharge of serotonin and histamine, vasodilator, which would maintain the status of vasodilatation of the artery with consequent compression of the nerve, thus creating a feedback system during the crisis. There are many other theories, including the question of whether it is before, the chicken or the egg, that is, if the nerve is inflamed for other reasons who initiates vasodilation, or whether, by contrast, is really the first vasodilatation phenomenon and inflammation resulting from it. Raised here because by accepting the first hypothesis that this may be the real mechanism of the crisis, and we began to build the global scenario. We will also accept, as we shall see below, which need not have such a disquisition of the chicken and the egg, the two concepts are not mutually exclusive.
Also we accept the idea as a second hypothesis, as expressed by the creators of sumatriptan, that vasodilatation is caused by the momentary lack of adequate levels of serotonin, which would be responsible for acting on 5HT1D receptors in the walls of the cerebral arteries, responsible for vasoconstriction. Sumatriptan was in fact designed as a selective agonist of serotonin, that means, serving as it, specifically acting on these receptors to produce vasoconstriction, which should have been produced by at least absent or inadequate serotonin.
Because of the CR
Either way, it is clear that the trigeminal nerve becomes inflamed in many circumstances in CR patients and not in a healthy individual. One might imagine that the neurochemical systems that regulate vasoconstriction and / or vasodilation of the cranial arteries operate incorrectly in CR patients, or, in other words, the CR patients suffering from excessive vasodilatation and that this would be the cause of the problem.
However, it is public knowledge that a patient may suffer a CR of a sudden crisis, or even start a cycle, by a direct action on the trigeminal nerve or its branches. Examples include oral infections, extractions mouth parts, the mere application of a pre-anesthesia tronculares manipulation, otitis and even trauma. If a direct action on the trigeminal nerve can cause a crisis immediately, without any intervention by neurochemical processes, we must conclude that the trigeminal nerve is damaged in some way.
Strengthens our hypothesis the sidedness of the event. If the processes were strictly neurochemical it would be difficult to explain that it only affects one side, and always the same. However, the consideration of physiological sensitivity of the nerve can explain this fact with absolute ease. We do not have the two sides never equal, there will always be a trigeminal more sensitive than the other and it will be the first to be inflamed.
The determination of whether damage is due to friction with the bone structure, damage or sensitivity of the neurons themselves, or any other cause, is outside of this dissertation. It would therefore be the primary cause of CR in this scenario: a particular sensitivity of the trigeminal nerve.
A sensitive trigeminal would ease to ignite at a vasodilatation bit severe, and even normal, in any case depending on the degree of sensitivity of the nerve and the intensity of the vasodilation. These two parameters are those that determine the method and level of suffering of each individual disease: being the sensitivity different for each individual, and although it may also theorized about the possibility of a sensitivity fall, it’s a stable parameter. By contrast, serotonin levels necessary to achieve a vasoconstriction that does not lead to inflammation are much more variable, and therefore, patients in CR are fully exposed and directly dependent on the levels of this neurotransmitter.
The facts explained on the basis of the hypothesis
We’ll begin to use our hypotheses to explain each of the facts relating to the CR.
One-Sided
From the hypothesis we can now easily explain why the disease manifests itself on one side, usually in the same, why the existence of changed hand and their rarity, and even the obvious that persons subject to unilateral surgery begin to suffer the crisis on the other side.
As we have said in passing, and will discuss later, when an inflammation of one of the two trigeminal begins, there is a release of serotonin from platelets. The released serotonin, which will finally end the crisis by vasoconstriction, reverses from the first moment the drop in the level and prevents the other nerve to be affected. This explains in a simple way the one-sidedness of the CR, although in theory there could be some cases, very unlikely, in which inflammation began almost exactly at the same time on both sides, then it would result in a bilateral crisis.
Neither holds any mystery in this scenario the fact of changing the side of the crisis. Some people may have similar sensitivity to both nerves and could ignite one or other without distinction, although it would not be normal. This group is small because it is a coincidence as the two eyes have the same height, just like seeing or hearing same level from both sides, or have both hands identical.
We explain that even within this already small group of people with similar sensitivity on both sides, as is normal that once a cycle on one side, stay there, and just because he has already undergone trigeminal daily sessions compression and inflammation is more sensitive and more likely to be the first to catch fire again.
People who receives stimulation by surgical techniques, or other padding to help one of the trigeminal to avoid inflammation, are just protecting the weaker of the two, this which started the crisis and thus protected the other. As serotonin levels drop to the level required by the other trigeminal, and without the surgered trigeminal intervention, the crisis will just change the side. We theorize that, since this is less sensitive than the other trigeminal surgery, the crisis may be less important.
Circadian rhythm
The explanation for the circadian rhythm is very simple, and that serotonin levels in the body follow a daily rhythm, marked by changes in daylight by the body directly on the retina (even without light, the day exists for the body but not 24 hours, just some 25 ½, this why “Circadian” in latin, “Circa die”, near a day). The level is highest at noon, and descends slowly as the day goes on. As we approach the darkness, we begin to transform the serotonin into melatonin, and its levels descends steeply into the night, reaching minimum at mid-dark. After that is replenished very slowly and rises again rapidly from the time we woke up and brought to light the eye, reaching back to maximum (midday) and back to start.
This explains why the most common and practically unavoidable, are crisis at night, especially during sleep. However, if our levels are really inadequate, in the morning, we can also suffer a crisis.
The hypothesis can make predictions about the multiple crises. As already mentioned, while suffering a crisis the platelets release serotonin, which acts sooner or later to produce adequate vasoconstriction and abort the process. After the crisis, the platelet re-capture the serotonin they had released, and when it comes back to the previous level, another crisis will begin.
Exacerbated this process by the reduction of serotonin throughout the day, we could theorize that anyone who suffers a crisis in the first hours of maximum levels, at the zenith of the day, must suffer more crises, because the standards of the rest of the day will always be lower . The elapsed time between two crisis is given by the time it takes platelets to re-capture that released serotonin and reduced to the extent that decreases serotonin in the body. Thus, the time between crisis should decrease as the day progresses, and minimum during the night.
Those who have high average levels, will face only a crisis everyday, in the middle of the night, preferably during sleep. Who has the crisis relatively quickly, well before bedtime, would run greater risk of repeating during sleep. Also it is expected that the time of serotonin reuptake by platelets is proportional to the time of release, that is, the duration of the crisis, so longer crisis should be more spaced in time, and shorter, more together in time.
These considerations are made with the circadian rhythm of serotonin as the only consideration, but not so far from it. Later we will see many other factors that affect serotonin levels and thus the behavior of the disease.
Rhythm circanual
Something that was already known, but it was not scientifically proven, is that the rate of serotonin varies with the seasons. The publication in September 2008 of some studies conducted in Toronto between 1999 and 2003 to a sample of 88 individuals has shown for the first time, no doubt, that the potential binding of serotonin transport are higher in autumn and winter than in spring and summer. Greater potential for the transport union, increased reuptake, less free serotonin available for neuronal transmission. However, the study shows two things. The first serotonin levels are markedly lower in autumn and winter than in spring and summer. The second, more exciting, there is an inverse correlation between total hours of daylight and time of the sunset with these levels.
So with this, it is easy to predict that arriving the fall and moving to lower levels of serotonin, some patients begin to experience difficulty, and as the winter comes, the other. Since February, the levels are restored gradually.
Again, there’s other factors involved here that can cause cycles in summer and prevent cycles in winter, but it is already obvious now that a great factor is that the fall / winter, or rather the hours of daylight and sunset hours are a increased factor for the start of the crisis.
Says study (conducted in the northern hemisphere, in Toronto) that in the southern hemisphere should occur equally in respect of the seasons, but with a rotation of six months of the calendar. He also said that he had found a small influence of moisture and age, and virtually none of the temperature.
Episodic and chronic
With our hypothesis in hand, it's easy to settle between people and people with episodic CR CR chronic. The episodic people are those whose serotonin levels are usually sufficient, but a circumstance in which an arrival time to drop these levels begin to engage in crisis and have insufficient levels until the end of the causes why the period of decline, forming the "cycles". The period is par season, but it can also come from other factors such as stress.
The chronically ill are simply those whose levels of serotonin are inadequate throughout the year. It seems valid to be considered that these patients would have more chance of remission in spring and summer and, with medium levels so low, they should be much more likely to suffer multiple crises, especially in autumn and winter. As a corollary, it follows that those who suffer from multiple daily crises, are proving insufficient levels, so it would in turn be more likely to become chronic with others who have more levels, for example, the people who have just a one night crisis.
In any case, given this scenario, there are no chronic or episodic, crisis is always suffered when serotonin levels are insufficient and will forward when eleven. The status of each one is always the circumstance of the moment, so that expressions such as "move to chronic" or "chronic", lack of the meaning they have in other areas of medicine, where the essential is the future remain. Here, a so-called chronic could stop their attacks from one day to another if it can raise its levels of serotonin.
Abortion: Oxygen and triptans
The only two known abortifacients, leaving aside various drugs, the triptans and oxygen. In neither case is known with certainty of their action, although it is accepted that in both cases it’s due to produce significant vasoconstriction, which would always end a crisis that is not excessive vasodilatation
As a crisis begins with a low level of serotonin, and that this level is not replenished by any means, only to be expected after the use of one or the other is that after a while and dismissed its impact, the crisis is restarted and even more strongly, as for the beneficial effects of the vasoconstrictor serotonin levels continued to decline.
There are two possibilities for this happening. The first is that in the time it takes to abort the crisis, it has freed enough to replenish serotonin levels and thus do not fall into a new crisis. This is more possible in patients of a single crisis that in the multiple, because this brief on first can allow replacement levels enough to not incur in another crises until the next day, making it possible more than a partial replacement of vasoconstriction over time are sufficient to avoid a reply. The latter, however, still suffering from the crisis not entirely replenished enough to prevent the next, so that the suffering resulting from the partial replacement of a crisis aborted early, can hardly avoid the effects following cessation of abortion.
Another possibility is that the use of an abortion is performed at night so that when the effect ceases, the levels of serotonin are replenished by its daily cycle.
Conclusions
Seems not to have found a cure here. If the problem is caused by a nerve, say, faulty, we are very far from being able to fix it with the knowledge of medicine today. So put this hypothesis to be adopted in one or more of the following measures:
1) Improving the status and situation of the nerve. 2) Increased levels of serotonin 3) Preventing falls in serotonin
Will be in another document in which I will enumerate and explore the means by which these objectives could be achieved, but we can not ignore the undisputed fact that serotonin levels in the body are good (except dysfunction), however by a good reason that currently only the body knows. Artificial lift will always disrupt our delicate neurohormonal balance, with unpredictable consequences.
There is also the added difficulty of homeostasis, the actual and expected reaction of the body who will try sooner or later to regain its previous situation.
It should, however, take a first step, without risk, and would be beneficial, measures to ensure that the body produces all that want to produce serotonin, ie, to avoid any gaps that are hindering the normal process the body. Not expected here, trying to cover deficits, homeostasis.
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