title: Geographic variation in one-year recurrent ischemic stroke rates for elderly Medicare beneficiaries in the USA.
abstract: BACKGROUND
  While geographic disparities in stroke mortality are well documented, there are no data describing geographic variation in recurrent stroke. Accordingly, we evaluated geographic variations in 1-year recurrent ischemic stroke rates in the USA with adjustment for patient characteristics.
  
  
  METHODS
  One-year recurrent stroke rates for ischemic stroke (International Classification of Diseases, 9th Revision codes 433, 434 and 436) following hospital discharge were calculated by county for all fee-for-service Medicare beneficiaries from 2000 to 2002. The rates were standardized and smoothed using a bayesian conditional autoregressive model that was risk-standardized for patients' age, gender, race/ethnicity, prior hospitalizations, Deyo comorbidity score, acute myocardial infarction, congestive heart failure, diabetes, hypertension, dementia, cancer, chronic obstructive pulmonary disease and obesity.
  
  
  RESULTS
  The overall 1-year recurrent stroke rate was 9.4% among 895,916 ischemic stroke patients (mean age: 78 years; 56.6% women; 86.6% White, 9.7% Black and 1.2% Latino/Hispanic). The rates varied by geographic region and were highest in the South and in parts of the West and Midwest. Regional variation was present for all racial/ethnic subgroups and persisted after adjustment for individual patient characteristics.
  
  
  CONCLUSIONS
  Almost 1 in 10 hospitalized ischemic stroke patients was readmitted for an ischemic stroke within 1 year. There was heterogeneity in recurrence patterns by geographic region. Further work is needed to understand the reasons for this regional variability.
authors.affiliation: Division of Chronic Disease Epidemiology, Yale University School of Medicine, New Haven,CT 06520-8034, USA.
authors.forename: Norrina B
authors.initials: NB
authors.lastname: Allen
authors.forename: Theodore R
authors.initials: TR
authors.lastname: Holford
authors.forename: Michael B
authors.initials: MB
authors.lastname: Bracken
authors.forename: Larry B
authors.initials: LB
authors.lastname: Goldstein
authors.forename: George
authors.initials: G
authors.lastname: Howard
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.forename: Judith H
authors.initials: JH
authors.lastname: Lichtman
mesh_terms: D001741:Black or African American; D000367:Age Factors; D000368:Aged; D001499:Bayes Theorem; D002545:Brain Ischemia / Q000453:epidemiology*; D015331:Cohort Studies; D005260:Female; D005843:Geography; D006630:Hispanic or Latino; D006801:Humans; D008297:Male; D006278:Medicare; D044469:Racial Groups; D012008:Recurrence; D012044:Regression Analysis; D012307:Risk Factors; D012737:Sex Factors; D020521:Stroke / Q000453:epidemiology*; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D044465:White People