Cluster headache (Bing-Horton neuralgia) is a serious primary headache disorder that even outstrips migraine attacks in its pain intensity. The pain usually manifests itself like an attack in the area of the eyes. Also typical is the periodic occurrence: Acute attacks of pain, which can last for several weeks or months (cluster period), alternate with headache-free phases (remission phase). Although the exact cause of the cluster headache is not yet clear, however, some trigger factors such as alcohol or heat are known. In order to alleviate the symptoms of the affected patients, both preventive and acute therapeutic options are available.
Cluster headache: symptoms
Cluster headaches start suddenly and usually affect only one face. They usually occur around an eye, but may also radiate towards the root of the nose, jaw, temple, forehead and neck. The pain is described by some sufferers as a "blazing hot knife in the eye" and also referred to as "suicide headache" due to its strength.
The duration of a pain attack can range from a quarter of an hour to three hours. The frequency of attacks ranges from one attack every other day to eight attacks daily. Cluster headaches are often associated with the following symptoms:
- Eye tears and red eyes
- Eyelid swelling and drooping eyelid
- nasal congestion
- Sweating in the area of the face
- Dizziness and nausea
- physical restlessness and strong urge to move
Experience has shown that headaches always occur at the same time of the day: they are most often noticeable one to two hours after falling asleep or in the early morning hours. In addition, there are seasonal accumulations of active cluster periods in spring and autumn.
Epidemiology of cluster headache
Cluster headaches are relatively rare compared to other types of headaches: less than one percent of the population is affected, while about ten percent suffer from migraines.
The headache mainly occurs in young men between the ages of 20 and 40 years. Why men are affected around three times more frequently than women has not yet been clarified.
Episodic and chronic course
Cluster headaches can occur in an episodic or chronic form. In an episodic course, the complaint periods last at least a week to over a year. In between there are symptom-free intervals of at least one month.
In contrast, chronic cluster headache is present if the headache attacks last longer than a year without improvement, there are no respite breaks or they are shorter than four weeks. About 80 percent of sufferers suffer from episodes and 20 percent from a chronic form.
Causes and inheritance
The exact causes of cluster headache have not yet been clarified. However, the fact that the headache is accompanied by an expansion of inflamed blood vessels in the brain is now excluded.
Rather, scientists suspect that a biological arrhythmia could cause cluster headaches. The hypothalamus plays a central role here. This forms part of the diencephalon and regulates body temperature, circulation and food intake as well as the biological day-night rhythm. This assumption is supported by the occurrence of cluster attacks, which is tied to day or season.
Some studies show that heredity also plays a role in the presence of cluster headaches: first-degree relatives experience up to 18-fold more headache and second-to-second relatives one to three times more frequently than normal subjects. However, the exact inheritance factors are unknown.
Trigger of cluster headache
During the active cluster period, some individuals may trigger certain internal and external stimuli called triggers, a cluster attack. Known triggers are alcohol, histamine and nitroglycerin.
Paradoxically, with alcohol, small amounts can provoke cluster attacks, while larger amounts can partially prevent an attack. The substance histamine is contained in strawberries, tomatoes, chocolate or red wine, for example. Nitroglycerin, which is used in medicines as an agent for the expansion of blood vessels, may also favor cluster attacks.
Other provocative factors are:
- flickering light
- extreme heat
- height changes
- Body stress
Such triggering factors, however, can only trigger attacks during the cluster periods, while they are ineffective during the remission phases.
Diagnosis of headache disease
Cluster headache is a condition that is diagnosed solely on the basis of the symptoms. Imaging procedures are at most suitable for excluding other causes of the complaints. The collection of the medical history and the occurring symptoms are accordingly the central means for the diagnostics.
Because of this, keeping a headache diary is useful for all recurring headaches. This makes it easier for the doctor to diagnose, to monitor the therapy and can help to find possible triggers. Also important for the diagnosis can be photos taken of the patient's face during an attack. Until a clear diagnosis is made, an average of five to seven years pass.
The nitroglycerin provocation test
The nitroglycerin provocation test provides a method to help diagnose a cluster headache. However, this method is ethically controversial and is hardly practiced these days.
In the test, a headache attack is intentionally induced by the administration of nitroglycerin during a cluster period. However, this only works if no spontaneous attack has occurred within the last eight hours, no vasodilator substances have been taken within the last 24 hours and no medical prophylaxis is being performed.
Treat cluster headache
In the treatment of cluster headache, conventional analgesics with drugs such as acetylsalicylic acid, ibuprofen or diclofenac are not effective. Even alternative therapies such as acupuncture or massage show no effect.
Basically, the most important thing is to avoid triggers (for example, alcohol, histamine, and nitroglycerin) during the cluster period. In the treatment of cluster headache, a distinction is generally made between treatment of acute single attack and preventive measures.
Acute therapy: what helps?
In acute therapy, the administration of 100 percent oxygen has proven to be extremely effective. In this case, the person affected via a high-concentration mask for 15 to 20 minutes, eight to 16 liters of oxygen per minute supplied. The inhalation of pure oxygen terminates the cluster headache attack in almost 80 percent of cases within a short time and is also free of side effects. The application is especially effective at the beginning of an attack.
Furthermore, the treatment with lidocaine, a means of local anesthesia, has proven itself. The substance is either placed in the nostril of the affected headache side or injected into the vicinity of a nerve tract to cause a nerve block.
The drug sumatriptan is also used for the acute treatment of cluster headaches. Sumatriptan interferes with the metabolism of serotonin, a key messenger in the treatment of pain. However, you may experience unpleasant side effects such as dizziness, tiredness, or drop in blood pressure when taking sumatriptan.
Prevent cluster headaches
For preventive therapy, corticosteroids and the active ingredient verapamil are preferred for both episodic and chronic cluster headaches. Lithium is also suitable for the treatment of cluster headaches. However, occasional side effects such as weight gain, lack of concentration or increased urination are associated with the intake.
In the case of drug therapy, care must be taken that the medications used for acute therapy and prophylaxis are compatible and compatible.
Although cluster headache has not hitherto been able to heal, the quality of life of the affected patients can be significantly improved by avoiding triggering factors and targeted therapy.