Paroxysmal vertigo as a migraine equivalent in children: a population-based study.

We studied the prevalence, causes and clinical features of paroxysmal vertigo (PV) in the well-defined childhood population of the City of Aberdeen. We applied a screening questionnaire to 2165 children (10% random sample of all children 5-15 years of age) attending schools in Aberdeen. Children with a history of at least three episodes of vertigo over the past year due to unknown causes were invited for clinical interview and examination. Children with PV were compared with a group of children with migraine, and with a group of asymptomatic children matched for age and sex. Forty-five children fulfilled the diagnostic criteria for PV (prevalence rate 2.6%, 95% CI 1.9-3.4). They were noted to have clinical features in common with children with migraine, including trigger and relieving factors, associated gastrointestinal and sensory symptoms, vasomotor changes, and a similar pattern of associated recurrent disorders (such as headache, abdominal pain and cyclical vomiting), atopic diseases and travel sickness. Also, they had a twofold increase in the prevalence of migraine (24%) compared with the general childhood population (10.6%). The overlap in the clinical features of PV and migraine suggests that the two conditions are related and that it is reasonable to continue to regard PV as a migraine equivalent.