Vestibular Migraine and the Overlapping Features Observed in those not Meeting Diagnostic Criteria

Background: For the first time in 2013, the international classification of headache disorders (ICHD) published a diagnostic criterion for vestibular migraine (VM). This provided, legitimacy to a diagnosis previously rejected by many, further driving a discussion regarding its validity.Objective: To characterize a cohort of patients suspected of having VM. Methods: Spanning a 3-year period, questionnaires were provided to patients at an outpatient neurotology clinic assessing ICHD diagnostic criteria for VM, and migraine.Results: Of the 396 participants included, 26% met criteria for VM, 25% met criteria for migraine only with no VM (MO), and 48% met no criteria (MNC) for either migraine or VM. Significant overlap in vertigo symptoms was observed in the MO group compared to VM participants, with only 3 of 11 features proving to be statistically different between the two. Similarly, 21 of 23 features of migraine were equivalent between the MO and VM group. In contrast, MNC and VM groups were significantly different in almost all features relating to migraine, vertigo and quality of life. Conclusions: Evidence of the significant symptomatic overlap observed in VM and MO groups demonstrates the two could be suffering from an identical disease process. In addition, the MNC group may belong to a benign recurrent vertigo entity due to a lack of features necessary to achieve ICHD criteria for migraine or VM. In all cases, there is evidence that migraine may play a significant role in vertigo symptoms, leading to a possible therapeutic improvement with migraine prophylaxis