Anticardiolipin antibodies in cluster headache.

Antiphospholipid antibodies have occasionally been observed in migraine patients, but a recent study of a large series suggested the association was with other concurrent conditions, not specifically with migraine. We wondered about an association with other vascular headaches and measured anticardiolipin antibody levels in 20 cluster headache patients during the cluster period (three during an acute attack). Platelet counts were normal and VDRL negative in all patients. No elevated anticardiolipin antibody levels were found. There appears to be no important association between the presence of anticardiolipin antibodies and cluster headache, and we argue that there is no further rationale for seeking one.