Migraine: a platelet disorder.

The hypothesis that migraine is caused by a primary abnormality of platelet behaviour was investigated in a total of 77 migraine patients and control subjects. Platelets taken from patients with classical migraine during a headache-free period demonstrated significantly higher spontaneous platelet aggregation and platelet adhesion than platelets from controls. Platelet 5-hydroxytryptamine release within three days of a migraine attack was significantly less than that measured during a migraine-free interval. Platelets from migraine patients differ significantly in their behaviour from normal platelets, and these differences can explain the onset and recurrence of attacks.