Unexplained dizziness does not resolve in time.

Only few patients with dizziness are referred to a medical specialist, who is sometimes unable to come to a conclusive cause of the dizziness. We have no information about the course of unexplained dizziness, from the literature or from our own population. We therefore undertook this follow-up study to assess the outcome of patients with unexplained dizziness, after assessment in a multidisciplinary outpatient clinic. In 292 patients (out of our total cohort of 2,244 patients), a diagnosis could not be established. The median dizziness handicap inventory (DHI) score at the diagnostic visit was 30. We sent them a questionnaire and the DHI. After a median follow-up of 62 months (range 24-105 months), 113 of the 189 responders (60%) reported to still suffer from dizziness, 46 patients had moderate impairments, and 16 patients indicated that they were severely impaired by their dizziness. The DHI only slightly decreased (from median 30 to 26). In 1% of the cases, an organic explanation for the dizziness was ultimately found during follow-up by other health-care workers. Patients who have been assessed in a multidisciplinary dizziness clinic, and in whom no explanatory cause for the dizziness has been found, have a high risk of persisting impairments.