Conditions that mimic stroke in the emergency department. Implications for acute stroke trials
R. B. Libman, E. Wirkowski, J. Alvir and T. H. Rao
Department of Neurology, Hillside Hospital, Long Island Jewish Medical Center, New Hyde Park, NY, USA.
OBJECTIVE: To determine if any clinical variables allow early
discrimination between stroke and other conditions presenting with a
strokelike picture. BACKGROUND: New therapeutic modalities for the
treatment of acute ischemic stroke are under active investigation. Many of
these treatments have potential adverse effects. It is well known that
noncerebrovascular conditions can present with a clinical picture mimicking
stroke, so early accurate differentiation of such "mimics" from true stroke
is essential. METHODS: Consecutive patients who presented to the emergency
department with an initial diagnosis of stroke between January 1990 and
January 1992 were evaluated. Chart review allowed these patients to be
classified into two final diagnostic groups: stroke mimic and true stroke.
Logistic regression was used to estimate the effects of predictor variables
measured at initial evaluation on the final diagnosis. RESULTS: There were
411 patients initially diagnosed as having stroke. Of these, 78 patients
(19%) were eventually found to have mimics, the majority comprising
postictal states, systemic infections, tumors, and toxic-metabolic
disturbances. Univariate analysis showed that decreased level of
consciousness and normal eye movements increased the odds of mimic, while
abnormal visual fields, diastolic blood pressure greater than 90 mm Hg,
atrial fibrillation on electrocardiogram, and history of angina decreased
the odds of mimic. Multivariate analysis showed that decreased
consciousness increased, while history of angina decreased, the odds of
mimic. Sensitivity of this model for predicting mimics was only 21% while
specificity was 96%. CONCLUSION: For the neurologist faced with an
immediate decision as to whether to randomize a patient with probable
stroke to an acute treatment protocol, these findings have some usefulness
but mandate further research into conditions that mimic stroke in the
emergency department.
