Head computed tomography findings predict short-term stroke risk after transient ischemic attack.
OBJECTIVE
Current guidelines recommend the use of head CT in the evaluation of patients with transient ischemic attack (TIA), but data supporting its value are sparse.


METHODS
Patients who presented to 1 of 16 emergency departments of a large Northern California health maintenance organization and received a diagnosis of TIA from November 1997 through February 1998 were enrolled and followed up for 90 days. Clinical, demographic, and outcome data were obtained from computerized databases and medical records. Physicians blinded to patient characteristics and outcomes abstracted head CT findings from radiology reports. Abstracted findings included evidence of old or new infarct, periventricular white-matter disease, cerebral atrophy, cerebral vascular calcification, and nonischemic lesions.


RESULTS
Head CT was performed in 67% of eligible patients (n=322) diagnosed with TIA. Evidence of a new infarct was seen on head CT in 13 patients (4%). A nonischemic cause of TIA symptoms was found in 4 patients (1.2%). During follow-up, 10.9% of TIA patients experienced subsequent stroke. After adjustment for confounders, risk for stroke during follow-up was significantly higher in those with a new infarct on head CT compared with others with TIA (odds ratio, 4.06; 95% confidence interval, 1.16 to 14.14; P=0.028). Old infarction, periventricular white-matter disease, cerebral atrophy, and cerebral vascular calcification were not predictors of subsequent risk of stroke.


CONCLUSIONS
Evidence of a new infarct on head CT in patients presenting with TIA is associated with increased short-term risk for stroke. Head CT appears to have prognostic value in patients with TIA and, for this reason alone, may be justified in their evaluation.
Douglas
Vanja C
VC
Department of Neurology, University of California, San Francisco 94143-0114, USA.
Johnston
Clarissa M
CM
Elkins
Jacob
J
Sidney
Stephen
S
Gress
Daryl R
DR
Johnston
S Claiborne
SC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California / Q000453:epidemiology; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000453:epidemiology; D015331:Cohort Studies; D015897:Comorbidity; D018572:Disease-Free Survival; D004632:Emergency Medical Services; D005260:Female; D005500:Follow-Up Studies; D006257:Head / Q000098:blood supply / Q000000981:diagnostic imaging*; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D020521:Stroke / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed