Cluster headache is a condition, characterized by recurrent severe headaches particularly on one side of the head. It is a neurological disorder, wherein the affected individuals would also experience associated symptoms such as conjunctival injection, nasal congestion, rhinorrhea, miosis or ptosis.
Development of severe, unilateral and sudden headache marks the onset of cluster headaches. Individuals usually experience headaches 2 to 3 hours after they fall asleep. Attacks can occur almost every day and can continue for several months. Headaches typically occur at the same time of the day, every day and last for about 15 to 180 minutes. Affected individuals experience the following signs and symptoms :
The following procedures are employed for diagnosing cluster headaches:
Cluster headache cannot be cured; it can however be effectively managed by reducing the severity of the symptoms. The major objectives for treatment of the condition involve shortening of the duration of attacks, reducing the frequency and decreasing the severity of headaches. Following are the methods which are employed for treating acute attacks of cluster headaches:
Cluster headaches can be severe enough to interfere with daily work and also affects the quality of life; however the condition is not life threatening. With appropriate treatment, it can be effectively managed. Cluster headaches do not permanently damage the brain .
The exact cause of cluster headache is not known. The disease is sporadic in nature; however some pieces of evidence suggest an autosomal dominant pattern. Abnormalities in the hypothalamus are known to play foul in the development of cluster headache. An increase in the activity of the hypothalamus has been noted in the affected individuals during the course of cluster headaches. The various risk factors for cluster headache include alcohol consumption, smoking and certain medications such as nitroglycerin .
The exact incidence rate of cluster headache in the US is unknown. Middle aged individuals are more prone to develop such a type of condition. However, in many instances, cluster headache can even affect small children aged 1 year and adults aged 79 years and above . Cluster headache is a rare phenomenon, with an estimated prevalence rate of 0.4% in men and 0.08% in women. Males are more prone to develop this condition compared to females, with male to female ratio being 6:1 .
The pathophysiology of cluster headaches is not properly understood. The periodic attacks suggest the involvement of human biological clock along with increase in activity of the hypothalamus . Diagnostic procedures have revealed that the major area of defect that gives rise to cluster headaches is the posterior hypothalamic grey matter. One of the mechanisms which have been understood, is that the attack is caused due to dilation of blood vessels which in turn exert pressure on the trigeminal nerve. Such a theory is known to give rise to the condition of cluster headaches .
Individuals are advised to avoid the various trigger factors such as smoking and alcohol. Maintaining a headache diary would also help in identifying the day and time of attacks which would help in preventing the onset of future bouts. Certain medications have also proved to be effective in preventing the development of cluster headaches. These include allergic medications, seizure medicines and hypertensive medicines.
Cluster headache is often confused with conditions of migraines, tension headache, sinus or the usual headache. Affected individuals may experience regular attacks for a period of 1 week to a year on a regular basis. This type of neurological condition belongs to a group of trigeminal autonomic cephalalgias. So far there is no known cure to treat cluster headaches. However, these can be prevented and the development of acute attacks can be effectively managed .