A nationwide study suggests that dizziness in the ED, although generally benign, appears to help clinicians indicate whether or not patients have serious neurologic disease. Dizziness was most often caused by peripheral vertigo (32%) or orthostatic hypotension (13%). Serious neurologic diagnoses were independently associated with:

Age older than 60.
Imbalance as the chief complaint.
Any focal examination abnormality.

Abstract: Mayo Clinic Proceedings, November 2012.