"Dizziness" is a nonspecific term often used by patients to describe symptoms. The most common disorders lumped under this term include vertigo, nonspecific "dizziness," disequilibrium, and presyncope. The first step in the evaluation is to fit the patient with typical symptoms into one of these categories.
The general approach to dizziness is reviewed here. The evaluation of vertigo and presyncope (the evaluation of which is the same as the syncope evaluation) are discussed in detail separately. (See "Evaluation of the patient with vertigo" and "Evaluation of syncope in adults".)
The reported proportion of patients with various etiologies of dizziness in community surveys , primary care setting [2,3], the emergency department [4-9], and the specialized dizzy clinic [10-14] are similar: approximately 40 percent of dizzy patients have peripheral vestibular dysfunction; 10 percent have a central brainstem vestibular lesion; 15 percent have a psychiatric disorder; and 25 percent have other problems, such as presyncope and disequilibrium (table 1). The diagnosis remains uncertain in approximately 10 percent. The distribution of causes varies with age. The elderly have a higher incidence of central causes of vertigo (approaching 20 percent), most often due to stroke.
The patient's description is critical for classifying the etiology of dizziness. In one series, the history was most sensitive for identifying vertigo (87 percent), presyncope (74 percent), psychiatric disorders (55 percent), and disequilibrium (33 percent) . The physical examination generally confirmed but did not make the diagnosis. Positional changes in symptoms, orthostatic blood pressure and pulse changes, observation of gait, and detection of nystagmus were most helpful on physical examination . Most psychiatric disorders were not detected prior to standardized psychological testing using the diagnostic interview schedule (DIS). Not surprisingly, no patients volunteered the likelihood of a psychiatric cause of dizziness.
Asking open-ended questions, listening to the patient's description of his or her symptoms, and checking and gathering additional information from specific questions should allow the clinician to form a hypothesis regarding the type of dizziness. As an example, a patient who says "I nearly blacked out" might be asked "Do you mean you nearly fainted?" An affirmative reply elicits another checking question, "So you felt you were passing out?" The clinician should also establish the time course, provoking and aggravating factors, concurrent symptoms, age, pre-existing conditions, and the findings on physical examination. These factors are especially useful to narrow the differential diagnosis when the patient’s subjective description is difficult to interpret, such as symptoms characterized as “wooziness”, brief sense of motion, or imbalance. The clinician can then decide on the need and extent of further testing and/or evaluation.