Posted by drummer (209.105.155.54) on December 11, 2000 at 09:02:08:
In Reply to: Cluster Crap. posted by drummer on December 11, 2000 at 08:33:46:
Cluster headaches occur primarily in adults between the ages of 20-40 years, with a male predominance of 80% to 90%. The age adjusted incidence is 9.8/100,000 person years, approximately 1/25th the incidence of migraine. The prevalence of cluster headache is 0.4%. The frequency of attacks ranges from 1 every other day to 8 per day. The pain associated with these headaches is excruciating; cluster headache is the most severe head pain syndrome known. Diagnostic criteria include at least 5 attacks of severe unilateral orbital, supraorbital, and/or temporal pain lasting 15-180 minutes, if untreated. Headaches occur with at least 1 of the following signs on the side of head pain:
These headaches are characteristically stereotypical. They are usually located behind the eye, and the pain is frequently described as boring or searing. Approximately 80% to 90% of patients experience episodic cluster, which occurs in periods of 7 days to 1 year, separated by pain-free episodes of at least 14 days. Chronic cluster occurs for more than 1 year without remission or with remissions lasting less than 14 days.
Alcohol is a trigger for cluster headaches. An autosomal-dominant inheritance has been proposed. Activation of the trigeminal ganglion may be responsible for the pain (Figure 5), with ipsilateral autonomic dysfunction of the cranial parasympathetics located in the superior salivatory nucleus.
Cluster headaches tend to occur at night. The circadian prominence suggests that the suprachiasmatic nucleus in the hypothalamus may also play a role in cluster pathogenesis. In addition, testosterone levels drop during an attack and melatonin production is reduced. Positron emission tomography (PET) studies suggest activation of the inferior hypothalamic gray matter during attacks induced by nitroglycerin.
Management of acute cluster headaches includes treatment with dihydroergotamine (DHE), ergotamine, lidocaine, oxygen, sumatriptan, and zolmitriptan. However, the goal of cluster management would be to prevent these headaches altogether. In general, when beginning prophylactic therapy, a transitional treatment is helpful. This allows the prophylactic medication to reach therapeutic levels without sacrificing headache control. Transitional treatment consists of a 10-day course of prednisone or a 7-day course of naratriptan or ergots.
Clinical experience suggests that verapamil is the best prophylactic treatment. However, 800 mg or more may be necessary before patients respond. AEDs, ergotamine, lithium, melatonin, and methysergide are also used. Valproic acid and topiramate are the only AEDs that have been found to be successful for preventing cluster headaches.
Hering and Kuritzsky, used 600-2000 mg/day of valproate to treat 13 patients with episodic cluster and 2 with chronic cluster. Nine of the 15 patients (60%) had a complete response, and 73% had a favorable response.
In an open-label study of topiramate, Wheeler and Carrazana evaluated 11 patients with episodic cluster, 3 with chronic cluster, and 1 with cluster-tic syndrome. They treated the patients with 70-100 mg/day of topiramate. Thirteen of the 15 (87%) patients achieved remission. Two patients did not tolerate topiramate because of fatigue. Headaches remitted 1-3 weeks after beginning topiramate (mean, 1.8 weeks).
Before diagnosing cluster headache, other disorders that can present with multiple attacks a day (eg, chronic paroxysmal hemicrania, an indomethacin responsive disorder) should be considered. Preventive therapy should be started early in cluster patients to minimize the need for acute treatment. AEDs should be started at a low dose and titrated to the maximum tolerated dose. Combination therapy can be very effective in treating cluster headaches.