The incidence of stroke mimics among stroke department admissions in relation to age group.

BACKGROUND: Acute stroke therapies are effective but may have serious adverse effects. This makes an accurate diagnosis mandatory. Acute stroke is diagnosed on the basis of neurologic findings, laboratory testing, and a computed tomography scan of the brain. This is the first study to investigate the incidence of stroke mimics beyond the triaging stage and just before therapy decisions across age groups.

METHODS: In all, 669 consecutive patients assessed at the emergency department by a neurologist were admitted to the stroke department with a provisional diagnosis of stroke. Patient registries of possible mimics were cross-referenced.

RESULTS: In all, 637 patients (95.2%) had a correct diagnosis of stroke. A total of 15 patients turned out to have migraine with prolonged aura, 13 had a conversion disorder, 4 had partial epilepsy, and one was hypoglycemic. Under the age of 50 years, stroke mimics occurred in 21% of 87 patients. Above the age of 50 years, stroke mimics were very rare (3% of 583 patients).

CONCLUSIONS: In patients being considered for acute stroke interventions, stroke mimics need to be considered particularly when the patient is younger than 50 years. In older patients, features typical of stroke mimics do not rule out a stroke.