Neurology/original researchVariables Associated With Discordance Between Emergency Physician and Neurologist Diagnoses of Transient Ischemic Attacks in the Emergency Department
Introduction
Cerebral transient ischemic attacks have been known to be a precursor for ischemic strokes for more than a century; however, the true risk of stroke shortly after transient ischemic attack has been well defined only in the last decade.1, 2, 3, 4 The risk of stroke after transient ischemic attack is 5% in the first 48 hours and ranges from 10% to 15% in the next 90 days, whereas the risk of other adverse cardiovascular events in the same period is 25%.1, 3 Previously, transient ischemic attack management was considered nonemergency and often managed in the outpatient setting. Recent guidelines for the management of transient ischemic attack have recommended hospitalization for severe transient ischemic attack or urgent referral and testing for recent transient ischemic attack.5, 6
The definition of transient ischemic attack has been controversial.7 A recent scientific statement from the American Heart Association has recommended the definition of transient ischemic attack to be a “brief episode of neurologic dysfunction caused by focal brain or retinal ischemia, with clinical symptoms typically lasting less than one hour, and without evidence of acute infarction.”6, 8 This definition eliminates the previous 24-hour time limit used to distinguish a transient ischemic attack from cerebral infarction. It also reclassifies patients with evidence of clinically silent acute cerebral infarction from transient ischemic attack to stroke. These changes have come in part from advances in neuroimaging that have shown that one third of transient ischemic attack patients have evidence of cerebral infarction on diffusion-weighted magnetic resonance imaging (MRI).6 Despite these changes, the diagnosis of transient ischemic attack still relies on an accurate interpretation of clinical history and physical examination leading to suspected focal brain ischemia.
Certain clinical features have been suggested to be atypical of transient ischemic attack, such as headache, incontinence, dizziness, and confusion.8 With the exception of dizziness, to our knowledge none of these atypical features have been evaluated to determine their association with a final diagnosis of transient ischemic attack. More recent tools have been used to assist with the accurate diagnosis of transient ischemic attack. The ABCD2 rule was developed as a risk-stratification tool for transient ischemic attack patients and the risk of subsequent short-term stroke.9 This rule has been assessed to determine whether higher ABCD2 scores predict true transient ischemic attacks. Two studies have shown that patients with higher scores at transient ischemic attack evaluation have a higher likelihood of correct transient ischemic attack or minor ischemic stroke diagnosis.10, 11
Appropriate ED diagnosis of transient ischemic attack is important because patients presenting with transient ischemic attack will often be admitted and undergo evaluations including computed tomography (CT), echocardiography, and carotid evaluation by means of ultrasonography or CT angiography and MRI/magnetic resonance angiography.12 These tests carry risks of radiation exposure and intravenous dye exposure and represent a significant medical expense. If prevalence of misdiagnosis were occurring at high rates, this would represent a major public health problem because transient ischemic attack is diagnosed in emergency departments (EDs) almost 300,000 times a year.13
The prevalence of correct transient ischemic attack diagnosis by emergency physicians is variable, according to previously published research. A recent study evaluating ED misdiagnosis of transient ischemic attack concluded the emergency physician prevalence of misdiagnosis of transient ischemic attack was 60%.14 Other studies have suggested that the prevalence of misdiagnosis is much lower, approaching 10% or less.10, 15 The ability of emergency physicians to accurately diagnose transient ischemic attack is important because rapid evaluation and treatment have been shown to decrease the rate of cerebral infarction.16, 17, 18 Once an incorrect diagnosis is made, inappropriate testing may occur, and it is uncertain when the inaccurate diagnosis will be corrected.
Practice patterns for neurologists' treatment of transient ischemic attack patients are unclear. Patients may be admitted and undergo testing only to be referred to a neurologist as outpatients. Also it is becoming increasingly common for transient ischemic attack patients to be admitted to observation units, where their evaluation will be completed by emergency physicians or hospitalists. These units are often protocol driven: testing may be ordered automatically. It may be the day after testing is complete before a neurologist decides that the patient had a non–transient ischemic attack event.
Our primary goal was to determine the prevalence of discordant diagnosis for patients receiving an ED diagnosis of transient ischemic attack compared with a neurologist's final diagnosis. Our secondary goals were to determine the frequency of atypical symptoms and what association these symptoms and the ABCD2 score had on a discordant ED transient ischemic attack diagnosis and to determine whether emergency physician experience was related to the risk of an ED transient ischemic attack discordant diagnosis.
Section snippets
Study Design
We conducted a planned secondary analysis of a previous retrospective cohort study evaluating all patients receiving an ED diagnosis of transient ischemic attack from January 2004 through December 2007. The primary study was an evaluation of the ability of the ABCD2 score, a transient ischemic attack prognostic tool, to predict positive results of diagnostic testing performed on transient ischemic attack patients.12 Our hospital is a county-owned ED with an annual census of more than 90,000
Results
We reviewed 436 subjects who received a diagnosis of transient ischemic attack in the ED, of whom 7 met exclusion criteria, allowing 429 subjects for final analysis. The demographics for the populations of discordant and concordant diagnoses can be seen in Table 1. These patients were evaluated by 47 unique emergency physicians with a median number of years of experience of 6 (interquartile range 2 to 12 years). The number of discordant transient ischemic attack diagnoses was 156 (36%; 95% CI
Limitations
This study has several limitations. It was conducted at a single center, so our results may not be applicable in other locations. The criterion standard of neurologist diagnosis of transient ischemic attack is problematic. Because there is no clinical diagnostic test that definitively diagnoses transient ischemic attack, we were limited to this criterion standard. The use of diffusion-weighted MRI was not considered as a surrogate criterion standard because a limited number of patients would
Discussion
Transient ischemic attack is a common disease that can present with a wide variability of clinical symptoms. The symptoms may be subtle, such as slight numbness or weakness, or as dramatic as hemiplegia or aphasia. The diagnosis of transient ischemic attack in the ED is a clinical diagnosis without the benefit of biomarkers or other diagnostic tests that may be of assistance. At this time, there is no current diagnostic test considered to be definitive for the diagnosis of transient ischemic
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Cited by (35)
Diagnosis of non-consensus transient ischaemic attacks with focal, negative, and non-progressive symptoms: population-based validation by investigation and prognosis
2021, The LancetCitation Excerpt :However, the high-level definition of TIA as a sudden, focal neurological deficit of presumed vascular origin lasting less than 24 h8,9 provides no guidance on which symptoms are likely to be vascular in origin. Agreement between clinicians regarding diagnosis of TIA is only moderate.10–14 Diagnostic criteria of the National Institute of Neurological Disorders and Stroke (NINDS) were developed by expert consensus to aid clinical practice and recruitment into research.9
Safety and Feasibility of a Rapid Outpatient Management Strategy for Transient Ischemic Attack and Minor Stroke: The Rapid Access Vascular Evaluation–Neurology (RAVEN) Approach
2019, Annals of Emergency MedicineCitation Excerpt :On average, RAVEN treated approximately 3 patients a week, and we found a 66% concordance rate between ED diagnosis of transient ischemic attack and minor stroke and final discharge diagnosis by vascular neurologists. This rate was similar to those of previous ED and general practitioner–based studies19,39,40 and notably better than that of an admitted transient ischemic attack cohort.41 The subjectivity in the diagnosis of transient ischemic attack highlights another important role for rapid outpatient transient ischemic attack and minor stroke evaluation: reassessment by another clinician (eg, in this case a board-certified vascular neurologist).
Managing Patients With Transient Ischemic Attack
2018, Annals of Emergency MedicineCitation Excerpt :These studies are problematic for several reasons. First, the criterion standard in both was the final neurologist’s diagnosis after incremental testing beyond the initial ED evaluation.15,16 Second, interobserver agreement about transient ischemic attack diagnosis is poor even among stroke-trained neurologists.17
Transient ischemic attack: A diagnosis of convenience
2017, American Journal of Emergency MedicineVascular Causes of Syncope: An Emergency Medicine Review
2017, Journal of Emergency MedicineCitation Excerpt :The wide number of etiologies requires careful consideration of dangerous vascular conditions. This is demonstrated in Table 2 (19–119). Characteristics of several types of vascular syncope are displayed in Table 1.
Impact of Hospital Admission for Patients with Transient Ischemic Attack
2017, Journal of Stroke and Cerebrovascular Diseases
Supervising editor: Allan B. Wolfson, MD
Author contributions: JWS, AV, and RKC were responsible for study design. JWS, MG, AV, and TL were responsible for data collection. JWS and RKC were responsible for statistical analysis and article preparation. JWS takes responsibility for the paper as a whole.
Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article as per ICMJE conflict of interest guidelines (see www.icmje.org). The authors have stated that no such relationships exist. Funding for Mr. Victor was provided by the Edward M. Chester, MD, Summer Scholars Program.
Publication date: Available online May 31, 2011.
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