Cluster Headaches

It can be difficult to determine if your head pain is due to a type of headache or a migraine, especially if you are prone to having both (Al-Karagholi et al., 2022). The comparison chart below may help you gain a better understanding of the differences between cluster headaches and migraines:

While the exact cause of CH remains uncertain, research has identified several risk factors, including (DiseasesDic, 2019):

• Gender: Men/AMAB are 4 times more likely to develop CH. This is believed to be due to testosterone’s effects on the widening of blood vessels, known as vasodilation. A higher testosterone level is believed to increase the risk of CH.
• Age: Men/AMAB are likely to develop CH in their 30s, while women/AFAB see it develop in their 60s.
• Genetics: If there is someone in your immediate family who has CH, you are 18 times more likely to develop it.
• Sleep disorders
• Smoking
• Frequent alcohol consumption
• History of migraines
• Prior head injury or surgery

The exact cause of CH is still unknown; however, years of research have identified three systems that play a role in CH (Del Mar Dominguez Garcia et al., 2023). These systems are:

• Trigeminovascular system: This system is composed of pain receptors found throughout the head and brain, and includes the blood vessels that pass through it and the neck. The unilateral pain felt during CH is caused by the activation of this system.
• Parasympathetic system: The parasympathetic system is primarily responsible for relaxation and many automatic (unconscious) body functions. The trigeminal nerve, which is part of the parasympathetic system, is believed to play an important role in CH. In particular, its activation causes the secondary non-pain symptoms of CH — teariness, congested sinuses, inflammation, and redness due to vasodilation on the affected side.
• Hypothalamus: The hypothalamus is responsible for keeping your body in a stable and balanced state. This is done through the release of hormones in response to information received from other parts of the body. It plays a part in creating testosterone and regulating your sleep cycle, both of which impact the risk of CH.

CH is characterized by sudden and repeated bouts of very severe pain located on one side of the head, usually starting or focused behind an eye.

Along with this specific pain pattern, some other common symptoms of cluster headaches, found on the affected side of the head, include:

• Red or inflamed eye
• Excessive teariness
• Congested sinus
• Excessive sweating
• Drooping eyelid
• Sound and/or light sensitivity

Other symptoms that may not be limited to a single side of the face include:

• Restlessness
• Pale skin
• Nausea and/or vomiting
• Visual aura
• Exhaustion following a cluster headache
• The headache occurs when triggered and/or at certain periods of the day

These CH will occur in episodes, meaning that over weeks or months, these CH will occur daily until they stop. This break in the CH pattern lasts at least 3 months unless you suffer from chronic CH, which is characterized by a headache-free period lasting less than a month.

The most frequent time for CH to occur is within the first 2 hours of sleep and may be associated with the REM sleep cycle.

Most people with CH report a consistent time frame for CH attacks, suggesting a strong link to their circadian rhythm.

A trigger is something that provokes a sudden reaction from a person, often uncontrolled or unexpected.

Some common triggers that may initiate a CH episode include (DiseasesDic, 2019):

• Smoking
• Alcohol: While frequent alcohol consumption is considered a risk factor, it is also a known trigger of CH in any amount once the first episode is experienced
• High altitudes and low oxygen environments
• Prolonged physical exertion
• Heat exposure
• Certain heart medications, such as nitroglycerine
• Bright lights
• High nitrate and nitrite foods, such as hot dogs, luncheon/deli meats, and bacon

A common factor among the known triggers of CH is the vasodilatory properties of those triggers. As such, vasodilation is considered a key trigger in CH, though the exact cause of this reaction is unknown.

To be diagnosed with cluster headaches, your doctor will discuss your symptoms with you, including how often these headache episodes occur, when they occur, and if you have any of the risk factors discussed above.

They will perform a physical exam to verify your reflexes and determine if there are physical signs that may suggest another cause for your symptoms.

They may also recommend an MRI or CT scan of your brain to rule out other neurological issues.

In 2021, Parakramaweeraet al. created a simple three-questions test to help identify CH.

If a patient answers yes to all three questions, then there is an 85% chance that they are suffering from CH.

The treatments for CH are divided into three types: acute, preventative, and transitional (Courault et al., 2021; DiseasesDic, 2019).

Acute treatments for cluster headaches include:

• Medications to stop the attack and relieve pain
• Oxygen
• Capsaicin cream for pain relief

Preventative treatments, which aim to prevent cluster headache episodes, are:

• Blood pressure medications
• Steroids to reduce nerve inflammation
• Addressing sleep issues to promote more consistent sleep cycles: This may include medication, therapy, and changes in habits affecting sleep
• Anti-seizure medications
• Antidepressants
• Muscle relaxants

Transitional treatment works to relieve the intensity and duration of cluster headache attacks until preventative medication can take effect. This treatment consists of taking corticosteroids, either as an oral dose or in the form of an injection under the affected eye.

In addition to these treatments, changes to your lifestyle may be needed. These changes would include stopping any smoking habits, creating better sleep-related habits, and reducing the amount of alcohol consumed.

Should none of the treatments help relieve your symptoms, then the last treatment option would be surgery to the trigeminal nerve, which is believed to be at the center of CH.

The Wilderman Medical Clinic offers the following treatment options for people with cluster headaches:

• Medication prescription for prevention of cluster headaches
• Vagal nerve stimulator for cluster headaches
• Nerve block injections for cluster headaches
• Psychotherapy
• Kinesiology education sessions