Psychiatric disorders and functional impairment in patients with persistent dizziness.

OBJECTIVE: To determine the prevalence and predictors of psychiatric dizziness and to measure functional impairment associated with dizziness.
DESIGN: Consecutive outpatients with a chief complaint of dizziness.
SETTING: Four outpatient clinics at a military teaching hospital. PATIENTS: 100 dizzy patients and 25 control patients.
MEASUREMENTS AND MAIN RESULTS: Structured psychiatric interviews were conducted using the Diagnostic Interview Schedule, and functional status was assessed with the Sickness Impact Profile and the 20-item MOS (Medical Outcomes Study) Short-Form. Psychiatric disorders were a primary or contributory cause of dizziness for 40% of the dizzy patients. Compared with the control patients, the dizzy patients had a higher lifetime (46% vs 32%) as well as recent (37% vs 20%) prevalence of axis I disorders. The greatest differences were in disorders of depression and somatization. The dizzy patients had a higher lifetime prevalence (23% vs 8%) as well as recent history (11% vs 0%) of major depression or dysthymia. Also, somatization disorders were strikingly more common among the dizzy patients than among the control patients (37% vs 8%, p = 0.005), with the dizzy patients reporting more than three times as many psychiatric or unexplained physical symptoms (5.2 vs 1.5). Age < 40 years, related complaints of weakness or headaches, and dizziness provoked by hyperventilation or standing were independent predictors of psychiatric dizziness. The dizzy patients reported moderate functional impairment, which was most severe among those with psychiatric disorders.
CONCLUSIONS: Persistent dizziness is associated with increased functional impairment and psychiatric comorbidity, particularly depression and somatization. Moreover, psychiatric disorders aggravate the impairment that occurs with dizziness alone.