title: Hospitalization for infection and risk of acute ischemic stroke: the Cardiovascular Health Study.
abstract: OBJECTIVE
  Little is known about the acute precipitants of ischemic stroke, although evidence suggests infections contribute to risk. We hypothesized that acute hospitalization for infection is associated with the short-term risk of stroke.
  
  
  METHODS
  The case-crossover design was used to compare hospitalization for infection during case periods (90, 30, or 14 days before an incident ischemic stroke) and control periods (equivalent time periods exactly 1 or 2 years before stroke) in the Cardiovascular Health Study, a population-based cohort of 5888 elderly participants from 4 US sites. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by conditional logistic regression. Confirmatory analyses assessed hazard ratios of stroke from Cox regression models, with hospitalization for infection as a time-varying exposure.
  
  
  RESULTS
  During a median follow-up of 12.2 years, 669 incident ischemic strokes were observed in participants without a baseline history of stroke. Hospitalization for infection was more likely during case than control time periods; for 90 days before stroke, OR=3.4 (95% CI, 1.8 to 6.5). The point estimates of risks were higher when we examined shorter intervals: for 30 days, OR=7.3 (95% CI, 1.9 to 40.9), and for 14 days, OR=8.0 (95% CI, 1.7 to 77.3). In survival analyses, risk of stroke was associated with hospitalization for infection in the preceding 90 days, adjusted hazard ratio=2.4 (95% CI, 1.6 to 3.4).
  
  
  CONCLUSIONS
  Hospitalization for infection is associated with a short-term increased risk of stroke, with higher risks observed for shorter intervals preceding stroke.
authors.affiliation: Department of Neurology, Columbia University, New York, NY, USA. mse13@columbia.edu
authors.forename: Mitchell S V
authors.initials: MS
authors.lastname: Elkind
authors.forename: Cara L
authors.initials: CL
authors.lastname: Carty
authors.forename: Ellen S
authors.initials: ES
authors.lastname: O'Meara
authors.forename: Thomas
authors.initials: T
authors.lastname: Lumley
authors.forename: David
authors.initials: D
authors.lastname: Lefkowitz
authors.forename: Richard A
authors.initials: RA
authors.lastname: Kronmal
authors.forename: W T
authors.initials: WT
authors.lastname: Longstreth
mesh_terms: D001424:Bacterial Infections / Q000150:complications / Q000175:diagnosis*; D002545:Brain Ischemia / Q000150:complications / Q000175:diagnosis*; D002309:Cardiology / Q000379:methods; D015331:Cohort Studies; D018592:Cross-Over Studies; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D008297:Male; D016017:Odds Ratio; D016016:Proportional Hazards Models; D012044:Regression Analysis; D012306:Risk; D020521:Stroke / Q000150:complications / Q000175:diagnosis*; D013997:Time Factors