[The clinical features of migraine-associated vertigo].

Migraine-associated vertigo (MAV) is proposed as a new clinical entity on the basis of the assumption that the typical migraine and vertigo or dizziness have a common pathophysiology. Some of the patients with recurrent vertigo syndromes with unknown pathology may have MAV. We performed a retrospective study to clarify the clinical characteristics of MAV in the Japanese population. The following were considered as diagnostic criteria: (1) recurrent vestibular symptoms, (2) migraine headache as defined by the International Headache Society (IHS) criteria, (3) at least one instance of synchronization of a vertiginous attack with a migraine headache, (4) no associated unilateral hearing loss, and (5) absence of other diseases that may have caused vertiginous attacks. Of 552 patients with dizziness or vertigo, 46 (8.3%) were diagnosed as having MAV. A typical feature of this clinical entity is that migraine occurs before the onset of vertigo in women aged 30-40 years. Usually the attacks occur once in a year for 1 to 10 years. An attack lasts for 1-24 h and presents as vertigo and unsteadiness with simultaneous headache. The presence of hearing loss presents an important clinical dilemma. Whether the condition in patients experiencing hearing loss should be defined as MAV or not is still a matter for discussion.