title: Recurrent events in transient ischemic attack and minor stroke: what events are happening and to which patients?
abstract: OBJECTIVE
  The risk of a recurrent stroke after transient ischemic attack (TIA) or minor stroke is high. Clinical trials are needed to assess acute treatment options in these patients. We sought to evaluate the type of recurrent events and to identify which subsets of patients are at risk for recurrent events.
  
  
  METHODS
  One hundred and eighty patients with TIA or minor stroke were examined within 12 hours and underwent brain MRI within 24 hours. Any neurological deterioration was recorded, and a combination of clinical and MRI factors were used to create a combined event classification. Subgroups of patients analyzed included classical TIA, patients with NIHSS=0, and patients with NIHSS >0 in ED.
  
  
  RESULTS
  Overall there were 38 events in 36 patients (20% event rate); 20 were symptomatic and 18 were silent (only evident because of the follow up MRI). 18/20 (90%) symptomatic events were associated with progression of presenting symptoms, compared to 2/20 (10%) with a clear recurrent stroke distinct from the original event. We found a low risk of recurrent stroke among classical definition TIA patients (1.1%). Patients with an NIHSS=0 in the ED, had an intermediate event rate (6.6%) between TIA (classical - 1.1%) and NIHSS >0 (14.4%; chi(2) test for trend, P=0.02). All clinical categories of patient (TIA, stroke, NIHSS=0) accumulated silent lesions on MRI.
  
  
  CONCLUSIONS
  Most events were classified as stroke progression or infarct growth rather than a recurrent stroke. A low risk of recurrence was found in patients with classical TIA and those with no neurological deficits on initial assessment.
authors.affiliation: Department of Clinical Neurosciences, Room C1246, Foothills Medical Centre, 1403 29th St SW, Calgary, AB, T2N 2T9, Canada. shelagh.coutts@calgaryhealthregion.ca
authors.forename: Shelagh B
authors.initials: SB
authors.lastname: Coutts
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hill
authors.forename: Cynthia R
authors.initials: CR
authors.lastname: Campos
authors.forename: Young B
authors.initials: YB
authors.lastname: Choi
authors.forename: Suresh
authors.initials: S
authors.lastname: Subramaniam
authors.forename: Jayme C
authors.initials: JC
authors.lastname: Kosior
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
mesh_terms: D000368:Aged; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D002546:Ischemic Attack, Transient / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology