Migraine headaches are complex and confounding, any way you look at them. For one thing, there is no clear-cut cause, no answer to why some people suffer from them, and others do not.
Among the possible causes are hormones and abnormal brain activity.
There is also no known single trigger.
Sufferers often point to stress, hormones, alcohol, lack of sleep or smoking as possible triggers. There’s evidence supporting all these possibilities.
There’s also the weather, terror attacks and fracking to think of.
But, as a 2013 study from Wake Forest Baptist Medical Centre in the US found: “It is nearly impossible for patients to determine the true cause of their migraine episodes without undergoing formal experiments.”
And even then, it can be tricky.
Treatment options
How wonderful that will be … one day.
Meanwhile, botulism injections, yoga, cosmetic forehead-lift surgery, electric brain stimulation, a smartphone relaxation app, and consuming a diet of more fish fats are among the treatments on offer.
Acupuncture is widely used to treat migraines, but the evidence for and against is mixed.
A randomised controlled trial in 2005 by German researchers found that acupuncture worked no better than a sham treatment.
But a systematic review of 31 randomised controlled trials published last year found it safe and effective.
The big picture
We know that about one in five women – and one in 15 men – suffer from migraines.
According to the Global Burden of Disease Study 2016 – an authoritative survey of health conditions across 195 countries – migraine attacks were the second-largest global contributor to years lived with disability.
Other surveys have placed migraines sixth as a disabling condition.
Whatever the case, migraines are a little-understood problem with a big impact on global health.
Research finds
In 2022, the American Academy of Neurology reported that women who get migraines may have a higher risk of pregnancy complications like pre-term delivery, gestational high blood pressure and pre-eclampsia.
In 2019, researchers from Harvard Medical School found increased thickness of two areas of the brain cortex in people who have migraines when compared to healthy controls.
As well as showing “that there are some structural differences in the brains of people with migraine, the position of the changes could help to explain why some people with migraine have problems with visual processing even in between attacks”.
This led to an independent observer from the Institute of Neurology, London, to conclude: “The new data show that after four millennia, migraine still has many more secrets to be uncovered.”
Dopamine?
In 2017, University of Michigan researchers used PET scans of the brain to show that dopamine falls and fluctuates at different times during a migraine headache.
This could help scientists “better understand dopamine-based therapies for migraines as well as a patient’s behaviour during an attack”.
In 2017, the Radiological Society of North America reported that migraine sufferers have significantly higher sodium concentrations in their cerebrospinal fluid than people without the condition. How does this help?
“These findings might facilitate the challenging diagnosis of a migraine.”
Stroke risk
It has long been believed that people who suffered migraines carry a greater risk of having a cardiovascular event. Some research contradicts this notion.
However, the prevailing thought was that people diagnosed with migraine had a higher risk of experiencing a heart attack or stroke before the age of 60.
Studies suggested that the increased risk of ischemic stroke – when a blood clot blocks a blood vessel to the brain – mostly affected young women.
A new study tells a more complicated story: Both men and women who experience migraine headaches carry a similar elevated risk of having an ischemic stroke.
But it’s women alone who might carry “an additional risk of heart attack and hemorrhagic stroke”, when an artery bursts in the brain.
Overall, the study suggests that migraines have a greater impact on women, beyond the question of numbers (migraines being predominantly diagnosed in women).
These findings, from Aarhus University, Denmark, were based on analysis of medical records collected from 1996 to 2018, from individuals aged 18 to 60.
The researchers “identified men and women with migraine based on their prescription drug records and compared their risk of a heart attack and ischemic and hemorrhagic stroke before the age of 60 to the risks faced by people in the general population without migraine”.
An earlier study and the aura
About one in five migraines are accompanied by neurological symptoms known as “aura”.
These symptoms include flashes of light, blind spots, or tingling in the hand or face.
Findings from a 25-year ongoing study of 12,844 adults presented at the American Stroke Association’s International Stroke Conference 2016, found that:
- Migraine with aura patients were 2.4 times more likely to have an ischemic stroke compared to patients suffering migraines without aura
- Migraine with aura patients were three times more likely to have an ischemic stroke caused by a mass or a clot that forms in the heart, dislodges and travels to the brain (cardioembolic stroke)
- Migraine with aura patients were twice as likely to have an ischemic stroke caused by a clot that develops in a clogged part of the blood vessel supplying blood to the brain (thrombotic stroke).
What’s going on here?
According to a 2020 review, the mechanism behind the migraine-stroke association is unknown.
However, neuro-imaging studies have revealed “a higher prevalence of asymptomatic structural brain lesions in people with migraine”.
Although stroke victims are more likely to have “unfavourable vascular risk factors” (such as clogged arteries), the increased risk of stroke “seems to be more apparent among people with migraine without traditional risk factors”.
In other words, migraine sufferers with aura who also suffer a stroke tend to be young, female and healthy. However, they appear to be compromised by “use of oral contraceptives and smoking habits”.
Beyond that, it’s one more migraine mystery.
On the upside, these increased stroke risks are small.
To learn more about the relationship between migraine and stroke, see here.
