The Migraine Mystery – Causes and Treatments’
We have all had a headache at some time, but headaches are not all the same and like all things medical are categorised and sub divided.
Headaches can be divided into Primary headaches and Secondary headaches. Primary headaches further subdivide into Tension, Migraine and Cluster headaches.
What Causes a Migraine?
The cause of the pain of migraine is not fully understood but the latest thinking is that a trigger causes an abnormal electrical event known as a Cortical Spreading Depression. This is a wave of electrical activity that spreads across the brain releasing neurotransmitters in an overreaction to the trigger. It is thought that the inflammation as a result of long-term migraine can even cause changes to the brain which may explain the change in symptoms over the years.
The Association of Migraine Disorders states how “almost all migraine sufferers have a problem with a specific part of the nervous system, called the trigeminal nerve. The trigeminal nerve is a network of wiring that attaches to special sensors.”
Firstly, someone who suffers from migraine is known as a migraineur. There is a school of thought that being a migraineur confers an evolutionary advantage as the migraineur’s brain is more active than usual, open to stimuli and generally more switched on.
What Triggers a Migraine?
Common Triggers of migraine are: stress, change in atmospheric pressure, lack of sleep, aromas.
Cheese, chocolate, and alcohol are commonly thought to cause migraines, but modern research surprisingly does not support this; the trigger with food and drink is usually based off going too long without eating and/or dehydration.
Likewise, eye strain is often thought to be a cause of headache but surprisingly there is little evidence that this causes headache, although eye strain may contribute to triggers – Prof Peter Goadsby, who in 2021 was awarded the world’s top Brain Prize from the Lundbeck Foundation for his pioneering migraine research, describes how it's rare for glasses to correct major problems with headache but not uncommon for a migraine sufferer to have a worsening of the headache because of some change in their prescription glasses.
Hormonal changes in women are another common trigger.
Some people suffer migraines after exercise. This is commonly due to not eating or drinking correctly leading to hypoglycaemia and dehydration.
Stages of a Migraine Attack
Migraine attacks can often, but not always, have distinct stages. Dr Mark Wetherall Consultant Neurologist from the London Headache Centre described the various stages as the following:
1st Phase: PRODROMAL (lasts a few hours to days) – warning phase. Symptoms typically include: food cravings, irritability, yawning, depression, difficulty sleeping and nausea. It seems to be mediated by stimulation of the dopamine circuits in the brain. Dopamine is a neurotransmitter present in behaviours involved in appetite or reward. Before a Migraine episode, people may get food cravings for a certain food.
2nd phase: AURA - phase of neurological dysfunction, typically just before headache. The most typical aura are visual positive aura like flashing lights or zig zags, or negative aura such as a blind spot. People can have sensory aura like a tingle or numbness spreading down the body, and people may have a motor aura affecting muscles which can involve difficulty speaking.
3rd Phase: PAIN - the most painful stage of a migraine, sometimes called the “attack” phase, usually characterised by a strong headache. Sensory processing areas of the brain send out signals that involve the release of chemicals, the most important being CGRP (Calcitonin Gene Regional Peptide).
4th phase: POSTDROME – around 20% suffer this phase which can go on for 2 to 3 days. Often described as a migraine hangover where the sufferer feels tired, depressed, and finds it hard to concentrate.
Susceptibility to migraines is thought to be inherited. One headache specialist nurse speaking on BBC radio 4’s Inside Health program described it as “the biology always sits, ready to be awakened”. American Neurologist Dr David Dodick described around 120 genes that have been identified that confer an increased risk of developing migraine. The more of these genes or their variations you have inherited, the more likely you are to experience more severe forms of migraine.
Migraines or any form of headache for that matter are not pleasant but reassuringly, they are rarely a sign of something more sinister. For example, a doctor described that of the people presenting in a migraine clinic who had brain scans, only 2 from 1000 scans showed up an anomaly requiring further investigation.
Studies have shown that during a migraine attack the release of CGRP – a small protein-is probably increased. One migraine treatment using monoclonal antibodies’ aims to stop CGRP binding to the cells which reduces the activity of cells involved in migraines.
Another common migraine trigger some may find surprising is pain killing medications – this is known as analgesic rebound.
Dr Andy Dowson, director of headache services from King’s College London, gave an example on BBC Radio 4’s Inside Health program from a study in a rheumatology clinic where patients were given painkillers for joints. Those that previously had migraine generally developed even more headaches, and those that had no previous migraine generally didn’t.
Dr Dawson went on to say that due to the analgesic rebound, migraine sufferers are often advised to give up long term medication in specialist headache clinics.
Is Migraine a Serious Problem?
Migraine is ranked globally, by the World Health Organisation, in people under the age of 50 as the single most disabling medical condition in the world and the leading cause of disability among all neurological disorders. It affects approximately 12% of the general population in Western countries, and affects three times more women than men.
Economic Cost of Migraine
An article published in 2019 in News Medical Life Sciences by Dr Ananya Mandal, MD stated that the cost of migraine attacks is estimated to be more than €27 billion per year in the EU . Almost a tenth of this cost is accounted for by the use of triptans to relieve symptoms, while $15 billion is accounted for by indirect costs such as work absenteeism.
The article quotes a US study that showed migraine accounted for an average of 8.3 days absenteeism and 11.2 days of reduced productivity per individual each year, with an overall estimated cost to employers of US$ 3,309 per sufferer.
In the UK migraine accounts for around 20% of the annual sick leave under the NHS as an employer in the UK. Migraine costs the NHS around £20 to £30 million per year and forms around 0.1% of total NHS expenditure.
So, any disease that accounts for around 20% of annual sick leave in a large organisation like the NHS - Britain’s largest employer - is a serious problem.
How To Manage Migraines
Thankfully, there are several methods of reducing and even eliminating the symptoms of a migraine.
The most common method is using migraine medication, such as Sumatriptan. This family of medicines narrows the blood vessels in the brain to reduce pain from migraine headaches. They are available from Pharmica, the UK’s trusted online pharmacy.
Alternatively, TENS (Transcutaneous Electrical Nerve Stimulation) devices are effective pain-relief tools that pass a mild electrical current through the body via electrodes attached to the skin, relieving migraines quickly and naturally. TensCare have released their new Mynd Migraine Relief device, which is a proven to be effective in the treatment and prevention of migraines.