Vestibular migraine - validity of clinical diagnostic criteria

Background: Clinical recognition of vestibular migraine (VM) is still hampered by the lack of consensus diagnostic criteria. The aim of this study is a long-term evaluation of clinical criteria for definite (dVM) and probable (pVM) vestibular migraine. Methods: We re-assessed 75 patients (67 women, age 24-76 years) with dVM (n = 47) or pVM (n = 28) according to previously published criteria after a mean follow-up of 8.75 +/- 1.3 years. Assessment included a comprehensive neurotological clinical examination, pure tone audiometry and caloric testing. Results: dVM was confirmed in 40 of 47 patients with a prior diagnosis of dVM (85%). Fourteen of 28 patients initially classified as pVM met criteria for dVM (50%), nine for pVM (32%). Six additional patients with dVM and two with pVM had developed mild sensorineural hearing loss, formally fulfilling criteria for bilateral Meniere's disease (MD), but had clinical features atypical of MD. Seven of these also met criteria for dVM at follow-up. The initial diagnosis was completely revised for four patients. Conclusion: Although VM diagnosis lacks a gold standard for evaluation of diagnostic criteria, repeated comprehensive neurotological evaluation after a long follow-up period indicates not only high reliability but also high validity of presented clinical criteria (positive predictive value 85%). Half of patients with pVM evolve to meet criteria for dVM. However, in a subgroup of VM patients with hearing loss, criteria for dVM and MD are not sufficiently discriminative.