MIGRAINE: DIAGNOSIS AND MANAGEMENT
- Correspondence to: Dr Giles Elrington, 119 Harley St, London W1G 6AU;
One in 10 people have migraine. The patient’s history is the essential diagnostic tool. Treatment options include acute rescue, lifestyle strategies, alternative remedies, and prophylactic drugs. Most patients are managed in primary care; many never consult a doctor. The triptans have improved acute treatment, and renewed scientific interest in migraine. Overuse of acute rescue medication can lead to chronic daily headache.
Spontaneous overactivity and abnormal amplification in pain and other, predominantly sensory, pathways in the brainstem, leads to migraine. Current opinion favours a primarily neural cause, involving feedback loops through innervation of cranial arteries in the trigeminovascular system.1 A relative deficiency of 5-hydroxytriptamine (5-HT) may be near the root cause, and is linked to the action of most drug treatments. Ongoing research is studying the relevance of calcium channel abnormalities, and peptides such as calcitonin gene related peptide, which may be closer than 5-HT to the underlying cause, offering hope for improved treatment in the future. Migraine is usually polygenic. Uncommon migraine variants, such as familial hemiplegic migraine and CADASIL, are single gene disorders. These are neurodegenerative, not primarily headache conditions.
Migraine is typically manifest by episodic disabling headache, though it is more than just head pain. Differential diagnosis is from tension type headache (TTH), with which migraine is co-morbid (this differential is also discussed from the other perspective elsewhere in this supplement). Migraine lasts hours or days, and is absent more often than it is present; the average attack frequency is once a month. TTH is often chronic and it is present more often than it is absent. Migraine should be distinguished from cluster headache, which is relatively rare and causes recurrent unilateral headache with autonomic dysfunction. The third, common though often challenging differential diagnosis is medication overuse headache (MOH). This typically complicates migraine which is then transformed …