How often does your stroke hospital misdiagnose stroke? If they don't even know that they should be closed. Not measuring missed diagnosis is actually a feature of stroke hospitals. That way they can be willfully blind, See no evil, hear no evil, speak/do no evil.
In the United States, more than 12 million people receive an
inaccurate medical diagnosis annually, and nearly every individual is
likely to be misdiagnosed at least once.
1,2 It is estimated
that at least 40,000 to 80,000 deaths per year result from such errors,
and 47% of hospital misdiagnoses lead to serious disability.
3,4
More than half of malpractice cases pertaining to emergency
departments (EDs) stem from diagnostic errors, and some findings
indicate these may be disproportionately high for neurologic conditions,
and especially
stroke.
5
Other research shows that misdiagnosis leads to death significantly
more often with cerebrovascular events compared with myocardial
infarction (45% vs 1%;
P <.001).
6
Although multiple studies have found elevated rates of stroke
misdiagnosis, including a study from 2014 demonstrating that up to 12.7%
of hospital stroke admissions were misdiagnosed initially, the precise
numbers are unclear because of wide variation in reported rates.
7 More
accurate "estimates would help clarify the burden of harms from
misdiagnosis and could help identify subgroups for which
misdiagnosis-reduction interventions should be sought," wrote Alexander
Andrea Tarnutzer, MD, from the University Hospital Zurich, Switzerland,
and colleagues in a new article published in
Neurology.8
To that end, they conducted a meta-analysis of 23 studies on
diagnostic accuracy pertaining to ischemic stroke, transient ischemic
attack, or subarachnoid hemorrhage, with a total of 15,721 patients.
Their findings show that nearly 8.7% of cerebrovascular events are
initially misdiagnosed in the ED, and rates are substantially higher for
patients with symptoms that are:
- Milder (subarachnoid hemorrhage with normal vs abnormal mental
state; false-negative rate, 23.8% vs 4.2%; odds ratio [OR], 7.03; 95%
CI, 4.80-10.31),
- Nonspecific (dizziness vs motor findings; false-negative rate, 39.4% vs 4.4%; OR, 14.22; 95% CI, 9.76-20.74), or
- Transient (transient ischemic attack vs ischemic stroke; false discovery rate, 59.7% vs 11.7%; OR, 11.21; 95% CI, 6.66-18.89).
To learn more about these results and how physicians might help reduce the frequency of such misdiagnoses,
Neurology Advisor spoke
with the study's senior investigator, David E. Newman-Toker, MD, PhD,
professor of neurology, ophthalmology, and otolaryngology at Johns
Hopkins University School of Medicine in Baltimore, Maryland; director
of the Division of Neuro-Visual & Vestibular Disorders; and director
of the Armstrong Institute Center for Diagnostic Excellence.
Neurology Advisor: What are the likely reasons for your finding that nearly 9% of patients with stroke admitted to the ED are misdiagnosed?
Dr Newman-Toker: The patients most likely to be misdiagnosed
are those with atypical stroke symptoms. Most often these are common,
nonlateralizing symptoms such as dizziness, vertigo, headaches,
confusion, or decreased level of consciousness. Roughly 95% of patients
presenting with such symptoms to acute care settings do not have strokes
as a cause, so finding these strokes requires the ability to separate
them from more common causes with high accuracy.
False-negative neuroimaging is more common than often imagined:
computed tomography misses >80%, and magnetic resonance imaging
misses 10-20% of acute ischemic strokes in the first 48 hours,
especially with posterior fossa infarctions. Many of the bedside
techniques to differentiate dangerous from benign causes (eg, vestibular
neuritis vs cerebellar stroke) rely on tests unfamiliar to most
emergency physicians and many neurologists, such as the head impulse
test of vestibulo-ocular reflex function as part of the HINTS
(Head-Impulse-Nystagmus-Test-of-Skew)
bedside test battery.
Neurology Advisor: What is the potential effect of these inaccurate diagnoses?
Dr Newman-Toker: Patients can suffer harms from delayed or
missed diagnosis through missed opportunities for acute stroke
treatments such as thrombolysis, critical care management of delayed
stroke complications, or early secondary stroke prevention. As a result,
some patients are left dead or disabled. Disproportionately, these
harms affect women, minorities, and especially younger patients.
Patients aged 18-45 years are 7-fold more likely to be missed than those
older than 75 years. One 18-year-old patient I know, for example, is
still trying to recover from locked-in syndrome after his initial
presenting symptoms of vertigo and vomiting from vertebral artery
dissection were misattributed to recreational drug use.
Neurology Advisor: What can neurologists do to improve stroke assessment and avoid misdiagnosis?
Dr Newman-Toker: Most patients with stroke are never seen by a
neurologist, so diagnosis relies largely on the neurologic diagnostic
skills of frontline care providers. This means neurologists need to
engage their emergency medicine colleagues, working together to identify
protocols and pathways for when to trigger appropriate neurological
consultation or initiate acute stroke therapies. It also means
neurologists must play a critical role in directly educating frontline
physicians and providing feedback when errors occur.
Neurology Advisor: What should be the next steps in terms of research in this area?
Dr Newman-Toker: Surprising as it may be,
there is no
systematic monitoring of diagnostic accuracy or missed stroke. The
critical next step is to begin operationally monitoring our diagnostic
performance in differentiating strokes from stroke mimics. This will
facilitate further studies to identify causes, develop and implement
systems solutions, and monitor impact of these interventions.
