There are several different types of headaches, some major categories are, tension, cluster, sinus, hormonal and many others. However, we are going to confine our discussion to a major category of headaches called migraines. In brief, migraines would be considered a neurovascular headaches. So in other words, these headaches are due to inflammatory changes occurring in the blood or vascular system of the brain and neck. It also involves the nervous system, particularly the autonomic nerves found within the blood vessels of the brain, skull and neck. Since migraines are vascular they respond to the pressure changes generated in the blood vessels by the beating of the heart. The pressure changes would account for the pounding/throbbing symptoms associated with this type of headache.
COMMON SYMPTOMS :
- Throbbing, pulsating, pounding pain can last from 4 to 72 hours.
- Sensitivity to light, photophobia.
- Sensitivity to sound, phonophobia
- Pain usually on one side of head at a time, but can be both sides.
- Visual or blurred vision.
- Nausea and/or vomiting.
- 1/3 of suffers experience a visual or some other sensory aura prior to the headache.
- Headache generally worsens with increased physical activity.
- Some may experience problems with speech, tingling in face, arms, hands or weakness on one side of the body.
It is estimated that about 37million people in the US suffer from migraines and about 13% of the adult population in the US experience migraines. 2-3 million are chronic suffers of migraines. 63% report that they have 1 or more migraines per month.
These types of headaches are usually found in people aged 35-55. Prior to the onset of menstruation in women the occurrence of migraines is about equal between both genders. However, of all suffers of migraines 70% are women. It is more common for women to suffer migraines around the time of their menstrual period. These statistics would seem to indicate a strong hormonal trigger for many migraines.
51% have stated that their migraines have reduced their work or school productivity. 91% found that their migraines caused them to miss work and that they cannot function normally. About 70% have had a family history of migraines. There may be a genetic component effecting some migraine sufferers.
TRIGGERS OF MIGRAINES
There are many “triggers” of migraine headaches. These “triggers are never totally identical between migraine sufferers and can vary within a single individual. Dawn Buse PhD and associate professor in the Department of Neurology at Albert Einstein College of Medicine at Yeshiva University states, “… within the same person triggers can be different from one day to the next, one week to the next”.
The triggers can be singular or cumulative. As an example, one patient may note that around the time of her menstrual period she will get a headache. Another may notice that this never happens to her, but, if she does not get good sleep, is stressed at work and that day we have a monsoon storm she will get a migraine. The triggers are also inconsistent. So at times someone will be able to eat some aged cheese with red wine and have no headache and another time be just fine. These observations regarding triggers may have to do with the levels of inflammatory changes that occur within both the vascular/ blood vessels, brain and nerves that control blood vessel dilation and constriction.
Let’s look at some of the common triggers of migraines.
Weather: About 1/2 of migraine sufferers complain about changes in heat, humidity and barometric pressure. It was found that people with migraines really could not predict the weather accurately due to migraine onset symptoms. Sorry! However, they could predict some sort of change atmospherically.
Hormonal: Changes in estrogen, progesterone, testosterone, thyroid , cortisol and other hormones may trigger migraines. However, it was found that hormone replacement or oral contraceptives in some people does help, others it does nothing and in others worsens the headaches. This observation may be due to relative function of the liver and proper microflora balance in the gut.
Certain Foods: Aged cheeses, marinated, pickled, fermented foods, red wine, alcohol, nuts, raisins, papaya, peanuts, broad beans, lima beans, fava beans, citrus, chocolate and processed meats containing nitrites and nitrates. Some of the reactions are due to tyramine, tannins, caffeine, and other food additives. Aspartame (Nutrisweet) is notorious for causing headaches. Please refer to a our prior newsletter on “Food Intolerances” for more information.
Sleep: Too much, to little or interrupted sleep. It is recommended that people with migraines should have a set sleep and wake schedule.
Perfumes and odors: Certain fragrances, cleaning products, smoke and other odors. This may be due to a deficiency of molybdenum. As there is an important enzyme that breaks down some of these compounds that depends upon this trace mineral..
Bright/flickering lights: fluorescent, strobe and LED lights, old computer monitors, and other devices.
Skipped meals: Irregular eating habits or skipped meals can lead to huge changes in blood sugar and hormones such as cortisol and insulin. This can lead to improper neural function and neurotransmitter imbalances in the brain.
Dehydration: About 65% of the body by weight is made up of water. Losing as little as 1- 2% of body weight in water leads to dehydration. 3-5% lose can lead to significant changes in reaction time, concentration and judgment. 9% or more is considered severe dehydration. Dehydration has widespread effects on the brain, nervous and muscular system by influencing the proper fluid dynamics, enzyme function and electrolyte balance.
Exercise and sex: In some, strenuous exercise or intense sexual experience can lead to migraines. This may be due to dehydration, misalignments in the neck or hormonal changes.
Heat and altitude: Heat is a tremendous stressor to the body. Altitude changes may also cause migraines due to changes in oxygen levels and barometric pressures.
MECHANISMS OF MIGRAINES
There is still a lot that needs to be learned about the actual causes of migraines. To date researches understand that migraines are not strictly vascular but, deeply involves the brain/ nervous system. There is a delicate interplay between the neurons in the outer lining of the brain known as the cortex or your grey matter, the lower part of your brain known as the brain stem, the blood vessels of the brain, the protective part of the brain known as the blood-brain barrier, microglial /immune cells, dural membranes that surround the brain and the various triggers previously discussed. In summary, the brain, nervous system, blood vessels and immune system are all involved with migraines.
Studies to date indicate a high correlation of migraine occurrence in offspring if parents suffered from migraines. The research has found that there is almost a genetic predisposition for migraines or as if some people are born “prewired” with genes for migraines. Even though you may have a genetic tendency this does not mean you will suffer from migraines.
About 1/3 of people with migraines experience a phenomena called an aura. This phenomena usually occurs about 1/2 hour before the onset of the headache. This is due to a wave like change in electrochemical activity along the surface of the brain (cerebral cortex) and is known as depolararization or more specifically cortical spreading depression (CSD). As CSD passes through different parts of the brain it can cause loss of vision, numbness, muscle weakness and hypersensitivity to light/sound. There often is a corresponding constriction of the blood vessel and changes in neurotransmitter activity.
The next aspect involves the pain sensitive tissues that are found in the blood vessels and surrounding membranes called the dura. The dura surrounds the brain, attaches to the inner lining of the bones of the skull, separates portions of the brain and contains many of the major blood vessels of the brain. If the blood vessels become inflamed from some of these triggers or the dura itself is physically distorted it may trigger dilation of the blood vessels resulting in headaches. There is also an interesting feedback that occurs to a nerve called the trigeminal nerve that originates in the brainstem. When this nerve center becomes abnormally stimulated it further worsens the dilation of the blood vessels. Both the trigeminal nerve and nerves from the upper neck have direct effects on the blood vessels and dura in the skull. This is why chiropractic adjustments and cranial manipulation can help with migraine headaches.
Lastly, the neurons in different areas of the brain such as the thalamus, brainstem and others can dysfunction and become hyper sensitized. Some of these triggers lead to inflammation of these neural centers causing their dysfunction. A number of these triggers along with other compounds can cause damage to a protective barrier along the blood vessels called the bloodbrain barrier. This causes neural inflammation, activates the brain’s immune system and leads to vascular problems.
MEDICAL TREATMENT OF MIGRAINES
We will briefly discuss some of the medications used to treat migraines. They can be broken down into two categories, preventative and acute/ abortive medications. Preventative: Beta blockers (Inderal), calcium channel blockers (Verapamil), antidepressants (amitriptyline, Ef fexor), anti-convulsants (Topomax, Depacon) and Botox muscle injections. Acute/abortive: Pain relievers (Ibuprofen, Tylenol, Excedrin Migraine), ergots (Migergot, Cafergot), triptans (Imitrex, Maxalt, Zomig). Most of these help to constrict blood vessels. There are also anti-nausea and narcotic medications. A new group of medications are called calcitonin gene related peptide (CGRP) antagonists. CGRP is released by certain nerve endings in the dural membranes and cause severe dilation of the surrounding blood vessels leading to headache pain.