title: Validation of the Stroke Prognostic Instrument-II in a large, modern, community-based cohort of ischemic stroke survivors.
abstract: OBJECTIVE
  The risk of recurrent stroke in the modern era of secondary stroke prevention is not well defined. Several prediction models, including the Stroke Prognostic Instrument-II (SPI-II), have been created to identify patients at highest risk, but their performance in modern populations has been infrequently tested. We aimed to assess the 1-year risk of recurrence after hospital discharge in a recent, large, community-based cohort of patients with ischemic stroke and to validate the SPI-II prediction model in this cohort.
  
  
  METHODS
  From 2004 through 2006, 5575 patients with acute ischemic stroke were prospectively identified and followed for recurrent events. Kaplan-Meier statistics were used to analyze the cumulative incidence of recurrent ischemic stroke. Harrell c-statistic was calculated to determine the performance of SPI-II in predicting stroke or death at 1 year, and the log-rank test was used to compare the differences among low-, middle-, and high-risk groups.
  
  
  RESULTS
  Among 5575 patients with ischemic stroke, recurrence was observed in 221 during the subsequent year. Kaplan-Meier estimates of cumulative rates of recurrent stroke were 2.5%, 3.6%, and 4.8% at 3, 6, and 12 months, respectively. Rates of stroke or death for SPI-II in the low-, middle-, and high-risk groups were 8.2%, 24.5%, and 35.6%, respectively (trend, P=0.001). The c-statistic for SPI-II was 0.62 (95% CI, 0.61-0.64).
  
  
  CONCLUSIONS
  The modern 1-year rate of recurrent stroke after hospital discharge is low but still substantial at 4.8%. SPI-II is a modestly effective tool in identifying patients with ischemic stroke at highest risk of developing recurrence or death.
authors.affiliation: Weill Cornell Medical College, Department of Neurology and Neuroscience, 525 East 68th Street, Room F610, New York, NY 10065, USA. ban9003@med.cornell.edu
authors.forename: Babak B
authors.initials: BB
authors.lastname: Navi
authors.forename: Hooman
authors.initials: H
authors.lastname: Kamel
authors.forename: Stephen
authors.initials: S
authors.lastname: Sidney
authors.forename: Jeffrey G
authors.initials: JG
authors.lastname: Klingman
authors.forename: Mai N
authors.initials: MN
authors.lastname: Nguyen-Huynh
authors.forename: S Claiborne
authors.initials: SC
authors.lastname: Johnston
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012306:Risk; D012307:Risk Factors; D055502:Secondary Prevention; D020521:Stroke / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control