Diagnosis of transient ischemic attack by the nonneurologist. A validation study.

Abstract

Interobserver reliability of the diagnosis of transient ischemic attack (TIA) is low, and diagnosis of TIA made by nonneurologists is often erroneous. We sought to validate the diagnosis of TIA made by general practitioners (GPs) and by hospital emergency service physicians (emergency MDs). A list of 20 neurological symptoms was distributed to 20 GPs and 22 neurologists who graded the compatibility of each symptom with the TIA diagnosis. At least two neurologists validated TIA diagnoses made by GPs for patients under their care or by emergency MDs. Compared with neurologists, GPs considered "confusion" and "unexplained fall" more often compatible with TIA and "lower facial palsy" and "monocular blindness" less often compatible with TIA. Validation of diagnosis by GP was confirmed in 10 patients (19%); 26 patients had strokes, and 16 (31%) had a noncerebrovascular disorder. Validation of diagnosis by emergency MD was confirmed in 4 patients (13%); 10 patients had strokes, and 17 (55%) had noncerebrovascular disorders. The most frequent conditions misdiagnosed as TIAs were transient disturbances of consciousness, mental status, and balance. The TIA concept is understood differently by neurologists and nonneurologists. GPs and emergency MDs often label minor strokes and several nonvascular transient neurological disturbances as TIAs. Until this misconception of TIA is changed, the term TIA should probably be avoided in the communication between referring physicians and neurologists. If not referred to a neurologist, one third to one half of patients labeled with a diagnosis of TIA will be inappropriately managed.