Keep it simple: vascular risk factors and focal exam findings correctly identify posterior circulation ischemia in “dizzy” patients

BACKGROUND: Dizziness is a common chief complaint of patients presenting to the Emergency Department (ED). Physicians must quickly and accurately identify patients whose etiology is most likely ischemia. Additional tools are available, but often require further training (vestibular testing) or are costly and not always readily available (magnetic resonance imaging (MRI)). This study evaluates the ability of a routine history and simple physical examination to correctly identify dizzy patients with posterior circulation ischemia, and the added utility of CT angiography (CTA). METHODS: We performed a retrospective analysis of all individuals presenting to the ED with a reported chief complaint of dizziness. Neurology was consulted and CTA ordered at the discretion of the ED provider. Demographic, medical, and radiographic variables were evaluated along with final diagnosis. Multivariable logistic regression and ROC analysis were used to determine factors associated with ischemia, the sensitivity of vascular risk factors and focal exam findings in predicting ischemia, and the additional benefit, if any, of CTA. RESULTS: One thousand two-hundred sixteen individuals meeting inclusion criteria presented to the ED over a 2 year period and were included in analysis. One hundred (8.2 %) were diagnosed with posterior circulation ischemia. For the entire cohort, age (OR 1.4 per 10 years, p < 0.0001), systolic blood pressure (OR 1.3 per 10 mmHg, p < 0.0001), and focal exam findings (OR 28.69, p < 0.0001) were most significantly associated with ischemia in multivariable modeling. When age, race, sex, presence of vascular risk factors, and focal neurologic findings were entered into ROC analysis, the AUC for correctly identifying posterior circulation ischemia was 0.90. In the subset of patients who underwent CTA (n = 87), the AUC did not improve (0.78 with and without CTA in ROC analysis, p = 0.52). CONCLUSIONS: A vascular risk assessment and neurological examination are adequate for risk stratification of ischemia in the dizzy patient and should remain the standard evaluation.