Migraines and Strokes – Is There a Link?

In recent years, researchers have noticed a worrying trend: more and more young people are having strokes. This is puzzling. Most strokes can be traced back to well-known, ‘traditional’ risk factors like blood pressure, obesity, smoking, type 2 diabetes, high cholesterol, or heart disease, which are common in older adults – but in younger people, those risk factors often don’t apply.

New studies point to migraine as a possible risk factor

One area now drawing attention in research is migraine. A major research study published in spring 2024 helped shine a light on this. At a university in Colorado, over 2600 patients who had experienced a stroke were examined, along with a control group of about 8000 people with no history of stroke. All participants were between 18 and 55 years old. The study was based on long-term observations showing a steady increase in stroke cases among people under 55 in high-income countries.

Until recently, most research had focused on traditional risk factors and their effects on blood vessels in the brain. This doesn’t explain why even seemingly healthy young people are having strokes, however. Another striking observation in this group of patients is that heart attacks and cases of sudden cardiac death are becoming less common. This calls into question whether stroke can be explained by traditional risk factors alone, since heart attack and sudden cardiac death are generally linked to the same causes as stroke.

Large-scale studies from the Netherlands and the U.S. have shown that women under 45 face a significantly higher risk of stroke compared to men. In contrast, among male patients aged 35 to 45, the number of heart attacks was twice as high as among females. This apparent contradiction between how often these conditions occur and what was previously thought to cause them led researchers to reassess the ‘traditional’ risk factors. As a result, they also began to consider possible ‘non-traditional’ causes.

Intriguing: risk factors are different in different age groups

In the Colorado study mentioned earlier in this article, researchers sorted health data by age group to get a clearer picture.

Among 18–34 year olds, cardiovascular diseases – high blood pressure in particular – were among the top stroke risk factors for both genders. But one surprising result stood out: migraine emerged as a more significant risk factor than high blood pressure.

In the 45–55 age group, diabetes, smoking, alcohol use, and kidney disease came into play, especially for men. But regardless of gender, migraine was again the most important non-traditional risk factor.

Overall, the data showed that traditional and non-traditional risk factors carry roughly equal weight when it comes to stroke.

Put simply: the older the person, the more traditional risk factors matter; the younger the person, the more non-traditional ones come into play. For people under 35, conditions like migraine, blood clotting disorders, autoimmune diseases, or kidney problems have a major impact. For those over 45, it’s more often the usual suspects: high blood pressure, high cholesterol, being overweight, and lack of exercise.

The tricky question of cause

It now seems clear that people with migraine face a higher risk of stroke. But identifying a statistical link is only the beginning. Scientists still need to figure out why that link exists. And that is always a much more difficult task.

Could migraine itself – and its effects – increase stroke risk? Are there genetic factors that both conditions share? Do the two diseases develop in similar ways? Researchers have looked into all these questions. Along the way, they did find some things that might help explain the connection. Much remains uncertain, however.

What is clear: the link between stroke and migraine is especially strong in women aged 18–34. This is important, because migraine is also much more common in women than in men. Could that help explain the risk?

At the center of the investigation: the blood vessels

One focus in the search for answers is the blood vessels themselves. In people under 55 who experience strokes, researchers have found that the number and function of key blood vessel cells are often reduced. These cells are essential for keeping vessel walls stable. Without them, blood vessels can become fragile and more likely to rupture. The risk increases if you have high blood pressure. This is exactly what happens more often than average in people with migraine. On top of that, the brain’s blood vessels in people with migraine tend to be more sensitive to spasms. Such spasms in the brain’s blood vessels can dangerously narrow the blood vessels and reduce the blood supply to the brain. In addition, the pressure can cause the blood vessels to burst.

Another risk comes from faulty blood platelets – the cells responsible for clotting, for example to stop bleeding if you cut yourself. In some cases, these cells clump together abnormally, forming clot-like masses (called thrombi) that can block small blood vessels. Sometimes, these cells don’t work the way they should. Instead of helping with normal blood clotting, they start sticking together on their own. These clumps of cells – also known as “thrombi” – can block even the smallest blood vessels. As a result, the surrounding brain tissue may not get enough oxygen and nutrients, or the pressure can cause already weakened vessel walls to rupture. This can have very serious consequences for the affected part of the brain.

A migraine attack itself also poses a risk

Migraine attacks place significant stress on the brain. They involve a process called cortical spreading depression. You can picture it as a wave-like burst of electrical activity that moves gradually across the outer layer of the brain, affecting large numbers of nerve cells. This is what triggers migraine pain. It also temporarily reduces blood flow in the affected regions. In severe or prolonged attacks, or in people with a family history, the affected areas of the brain can be damaged, leading to symptoms typical of a stroke.

The role of hormones

For women with migraine, hormonal birth control pills are a known risk factor. Even without additional factors, women already have a higher stroke risk than men. But with hormonal contraceptives, that risk increases significantly. One study commissioned by the World Health Organization (WHO) found that women with migraine who use hormonal birth control are eight times more likely to have a stroke than women with migraine who don’t use these products. Other studies have found a higher risk linked to hormone replacement therapy used to ease menopause symptoms. So it’s clear: hormonal influences play a major role in stroke risk.

Knowledge is key to prevention

The connection between migraine and stroke is complicated. Many risk factors are involved. These risk factors sometimes interact with each other. Age and gender are important too. Despite many research efforts, science has not yet found a complete explanation for how these factors work together.

However, ongoing research is helping patients better understand their own risk. With expert medical support, personal risks can be identified early and treated as effectively as possible. Regardless of the link between migraine and stroke, patients can greatly improve their symptoms through personalized migraine prevention. The lasting benefits of these approaches are now well proven. In fact, patients who follow preventive measures based on their own migraine patterns often see a clear reduction in how often and how severe their attacks are.