Understanding Stroke Patients' Headaches: Causes And Mechanisms

Headaches are among the lesser-known consequences of strokes, with about 10-15% of stroke survivors experiencing new headaches shortly after a stroke. Headaches can be a distracting and painful symptom of a stroke, and they may even limit a person's ability to participate in their usual activities. While the exact mechanism of stroke-induced headaches is not fully understood, it is believed that injury to sensory regions of the brain, alterations in brain electrical activity, and changes in blood flow following a stroke may all contribute to the development of headaches. It is important to note that headaches can be a warning sign of an impending stroke, and seeking medical attention is crucial.

Headaches may precede a stroke

Headaches are a commonly reported but poorly understood phenomenon that can precede a stroke. While the exact mechanism of these headaches is not yet known, they are thought to be a warning sign of an impending stroke. Here's what you need to know about headaches that may precede a stroke:

Sentinel Headaches

Sentinel headaches are a type of headache that occurs before a stroke and acts as a warning sign. In a study by Lebedeva et al. (2020), 17.1% of patients experienced headaches during the seven days before their stroke. This prevalence is significantly higher than in the control group, indicating a possible link between new or altered headaches and an increased risk of stroke. Sentinel headaches are defined as a new type of headache or a previous kind of headache with altered characteristics, such as severe intensity, increased frequency, or absence of effect from drugs. These headaches should alarm individuals and healthcare professionals about the possibility of an impending stroke.

Risk Factors and Triggers

Several factors have been identified as potential triggers or risk factors for sentinel headaches and stroke. These include:

• Female sex
• Atrial fibrillation
• Angina pectoris
• Previous history of headaches, including migraine and tension-type headaches
• Attacks of arrhythmia
• Embolism
• Dilatation of cerebral arteries
• Alterations in the electrical activity of the brain

Distinguishing Sentinel Headaches

It can be challenging to distinguish between a benign headache and a sentinel headache. However, there are some key differences to look out for:

• Sentinel headaches often have altered characteristics compared to previous headaches, such as increased intensity, frequency, or duration.
• Sentinel headaches may be unresponsive to drugs or pain relief medications previously used for headaches.
• Sentinel headaches may be accompanied by other stroke-like symptoms, such as disorientation, a general feeling of being unwell, changes in vision, or vertigo.

Seeking Medical Attention

If you experience a new or altered type of headache, it is crucial to seek medical attention. While most headaches are not a cause for concern, some may be a warning sign of an impending stroke. Healthcare providers can help determine the underlying cause of your headache and provide appropriate treatment or preventive measures. Additionally, early treatment can help prevent a stroke and reduce the risk of permanent brain damage.

Migraines and stroke

People who suffer from migraines, especially women, seem to have a higher risk of stroke. Migraine with aura, in particular, is associated with a doubling of the risk of ischaemic stroke. However, the overall risk linked to migraine is still very low, and other risk factors like smoking and high blood pressure are more significant.

The precise causes of the link between migraines and strokes are unclear, but various theories have been proposed, including cortical spreading depression, endovascular dysfunction, vasoconstriction, and neurogenic inflammation.

Migraine Aura and Stroke

Migraine aura can sometimes mimic the symptoms of a stroke, such as weakness down one side of the body, difficulty speaking, and visual disturbances. However, the onset of migraine aura symptoms tends to be slower than the sudden onset of stroke symptoms. Additionally, migraine headaches are typically one-sided and throbbing, while stroke-related headaches can occur anywhere on the head and cause sensations to be lost.

Migraine Treatment and Stroke Prevention

For people with migraine with aura, it is recommended to avoid smoking and taking oral contraceptives with high estrogen doses, as these can increase stroke risk. Other lifestyle changes, such as stopping smoking, losing weight, healthy eating, and exercise, can also help reduce stroke risk.

While there is no evidence that any preventive therapy for migraines should be used to decrease stroke risk, managing other risk factors for stroke is essential.

Post-stroke headaches are treatable

Headaches are a common symptom of strokes, with around 7-65% of people experiencing some form of a headache during a stroke. While they can be distracting and painful, post-stroke headaches are treatable.

Types of Post-Stroke Headaches

Post-stroke headaches can fall into several categories, including medication overuse headaches, tension headaches, and migraine headaches.

Medication Overuse Headaches

Medication overuse headaches are caused by excessive use of painkillers. Your doctor can help you develop a schedule to gradually reduce your use of painkillers to prevent medication overuse headaches.

Tension Headaches

Tension headaches are usually associated with photophobia (sensitivity to light), phonophobia (sensitivity to sound), or mild nausea. They are typically easy to control with mild medication and rest.

Migraine Headaches

Migraines are very painful and may be associated with nausea, neurological symptoms, and fatigue. They may require powerful prescription medications. Because some migraine medications are not recommended for people with heart disease or stroke, you may need to see a neurologist to manage your migraines.

What to Do About Post-Stroke Headaches

If you experience headaches after a stroke, it is important to talk to your doctor for two reasons. First, they can determine if your headaches are a sign of a more serious problem. Second, they can provide treatments to reduce the frequency and severity of your headaches.

Why Post-Stroke Headaches Occur

Post-stroke headaches may be related to stroke-induced injury to sensory regions of the brain, alterations in brain electrical activity, or changes in blood flow in the brain.

While the exact mechanism of post-stroke headaches is not fully understood, effective treatments are available. If you are experiencing post-stroke headaches, consult your healthcare provider to discuss treatment options and manage your pain.

Sentinel headaches as a warning sign of stroke

Sentinel headaches are warning signs of an impending stroke. They are sudden, intense, persistent headaches with features different from previous headaches. Sentinel headaches can precede a stroke by days or weeks and occur in 10-60% of patients with spontaneous subarachnoid haemorrhage.

Sentinel headaches are defined as a new type of headache or a previous kind of headache with altered characteristics (severe intensity, increased frequency, absence of effect of drugs) within seven days before a stroke. They are significantly more prevalent in stroke patients than in control groups. The sudden onset of such headaches should be a warning sign of stroke.

Sentinel headaches are more prevalent in women, and a previous primary headache increases the risk of a sentinel headache. Sentinel headaches may be caused by embolism, which impacts the vascular endothelium of cerebral arteries by liberating cytokines that dilate the vessels and cause proinflammatory effects.

Sentinel headaches are a warning sign of stroke, and their recognition and treatment are important to improve patient outcomes.

Headache characteristics and triggers

Headaches are among the lesser-known consequences of strokes, with about 10-15% of stroke survivors experiencing new headaches shortly after a stroke. However, the prevalence of headaches after a stroke ranges from 7-65%, with some studies reporting a higher incidence of 54%. The characteristics and triggers of headaches resulting from strokes are discussed below.

Characteristics

Headaches that begin after a stroke are not necessarily correlated to the location of the stroke within the brain. However, the area affected by the headache is often directly related to where the stroke occurs. For instance, a blocked carotid artery can cause a headache on the forehead, while a blockage towards the back of the brain can cause a headache towards the back of the head.

The intensity of stroke-related headaches is usually described as severe, and they can be challenging to differentiate from migraine headaches. Both types of headaches share some overlapping symptoms, including disorientation, a general feeling of being unwell, changes in vision, and vertigo. However, migraine headaches are often characterised by sensations like auras, flashing lights, or tingling skin, while stroke-related headaches cause sensations to be lost, such as a loss of vision or feeling. Additionally, the pain associated with migraine headaches is typically described as a throbbing sensation that gradually worsens, whereas stroke-related headaches cause sudden and severe pain.

Triggers

There are several potential triggers for stroke-related headaches. One possible trigger is a "mini stroke," or transient ischemic attack (TIA), which is a temporary interruption of blood flow that can cause identical symptoms to a stroke. Additionally, certain medications, such as dipyridamole (a blood thinner used to prevent strokes), can trigger headaches in some individuals.

Furthermore, in the case of haemorrhagic strokes, ongoing bleeding can lead to swelling and increased intracranial pressure, which can be a trigger for headaches. This complication is experienced by about 40% of patients who have had a haemorrhagic stroke.

It is important to note that the exact pathophysiology of headaches after a stroke is not yet fully understood and requires further research.

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