Migraine as a Stroke Mimic and as a Stroke Chameleon

DOI: https://doi.org/10.1007/s11916- 019- 0801- 1

Abstract-Summary This review details the frequency of and ways in which migraine can be both an ischemic stroke/transient ischemic attack mimic (false positive) and chameleon (false negative).

Nearly 2% of all patients evaluated emergently for possible stroke have an ulti- mate diagnosis of migraine; approximately 18% of all stroke mimic patients treated with intravenous thrombolysis have a final diagnosis of migraine.

Migraine is a common incorrect diagnosis initially given to patients with stroke. Among patients discharged from an emergency visit to home with a diagnosis of

a non-specific headache disorder, 0.5% were misdiagnosed.

Both failure to identify cerebral ischemia among patients with headache and

overdiagnosis of ischemia can lead to patient harms.

While some tools exist to help with acute diagnostic decision-making, additional strategies to improve diagnostic safety among patients with migraine and/or cere- bral ischemia are needed.

Extended: The pressure to make fast diagnostic and treatment decisions may lead

to stroke overdiagnosis [211].

Acute ischemic stroke can cause a secondary headache or trigger a migraine

attack [212].

This review will focus on migraine as a mimic and as a chameleon of ischemic

cerebrovascular disease, with a special emphasis on recent findings.

Developing clinical decision support tools, encouraging the use of existing clini- cal scores, identifying cerebrovascular biomarkers, improving neuroimaging utili- zation, and further exploring approaches used to improve diagnostic accuracy in similar disease states represent important future directions.

Introduction There are thus two broad categories of ischemic stroke misdiagnosis: stroke mimics and stroke chameleons.

Stroke mimics are false-positive cases and stroke chameleons are false-negative

cases [213].

3.3 Clinical Diagnosis

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Migraine with aura is a well-recognized stroke risk factor, aura symptoms can mimic focal neurologic deficits, and migraine can cause cerebral infarction [214, 215].

Acute ischemic stroke can cause a secondary headache or trigger a migraine

attack [212].

This review will focus on migraine as a mimic and as a chameleon of ischemic

cerebrovascular disease, with a special emphasis on recent findings.

Migraine as a Mimic Patients may report acute rather than gradual or spreading onset and/or incorrect lateralization [16, 216, 217], which further complicates distinguishing between migraine aura and stroke on clinical grounds.

A total of five stroke mimic patients included in one of the FABS derivation

cohorts had a final diagnosis of migraine [218].

In the derivation cohort, headache/migraine with or without aura was the alterna-

tive diagnosis in 2.9% of included stroke mimics [219, 220].

Among patients with transient neurologic deficits, older age, male gender, and history of stroke, hypertension, or dyslipidemia were significantly more frequent among patients with TIA as opposed to those with migraine with aura or migraine aura without headache [221].

Almost 2% of all patients evaluated in the ED for possible stroke have migraine; migraine with aura was the final diagnosis in approximately 18% of stroke mimic patients acutely treated with thrombolysis included in the systematic review [222].

Migraine as a Chameleon When a patient presents with headache at the same time or in close temporal prox- imity to acute ischemic stroke or TIA symptom onset, the two events are synchro- nous and thus related.

Patients with cerebral ischemic events may have headaches not temporally

related to their stroke/TIA.

If a patient with asynchronous headache and migraine is misdiagnosed, whether they are a stroke mimic or a stroke chameleon will depend on their presenting symp- toms and their true underlying disease process.

It is not uncommon for patients with true ischemic stroke or TIA to complain of

a headache [223, 224].

In a recent meta-analysis of 15,721 patients across 23 studies reporting diagnos- tic accuracy for ischemic stroke, transient ischemic attack (TIA), and subarachnoid hemorrhage (SAH) in the emergency setting, investigators found that migraine or non-migrainous headache was the most common diagnosis (26.1%) in cases of mis- diagnosis [225].

Conclusion The prevalence of headache among patients with acute cerebral ischemia, the diverse nature of migraine aura phenomenology, and the limitations of current diag- nostic neuroimaging contribute to diagnostic uncertainty.

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3 Diagnosis

The absence of explicit diagnostic criteria for TIA or an objective marker that a cerebrovascular event has occurred are impediments to discriminating between migraine aura and TIA.

Developing clinical decision support tools, encouraging the use of existing clini- cal scores, identifying cerebrovascular biomarkers, improving neuroimaging utili- zation, and further exploring approaches used to improve diagnostic accuracy in similar disease states represent important future directions.

Acknowledgement A machine generated summary based on the work of Otlivanchik, Oleg; Liberman, Ava L. 2019 in Current Pain and Headache Reports

Differentiating migraine, cervicogenic headache and asymptomatic individuals based on physical examination findings: a systematic review and meta-analysis