Background. Although dizziness is a common symptom in both primary care and
referral practices, the relative frequency of various causes has not been
well delineated.
Methods. A MEDLINE search identified 12 articles containing original data o
n the etiology of dizziness in consecutive patients. Study sites included p
rimary care offices (n = 2), emergency room (n = 4), and referral clinics (
n = 6). Each study's strength of design was graded using nine quality crite
ria.
Results. Dizziness was attributed to a peripheral vestibulopathy in 44% of
patients, a central vestibulopathy in 11%, psychiatric causes in 16%, other
conditions in 26%, and an unknown cause in 13%. Certain serious causes wer
e relatively uncommon, including cerebrovascular disease (6%), cardiac arrh
ythmia (1.5%), and brain tumor (<1%).
Conclusions. Dizziness is due to vestibular or psychiatric causes in more t
han 70% of cases. Since serious treatable causes appear uncommon, diagnosti
c testing can probably be reserved for a small subset of patients.