title: Geographic variation in implantable cardioverter-defibrillator use and heart failure survival.
abstract: BACKGROUND
  Implantable cardioverter-defibrillators and cardiac resynchronization therapy-defibrillators (ICD/CRT-Ds) are evidence-based preventative treatments for many patients with heart failure (HF), yet large numbers of eligible patients remain untreated. It is uncertain if localities with more frequent ICD/CRT-D use have had better rates of HF survival.
  
  
  OBJECTIVE
  To determine if US Hospital Referral Regions (HRRs) with larger increases in the rate of ICD/CRT-D utilization during 2002 to 2007 also had commensurate increases in HF survival.
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  Medicare beneficiaries age 66 to 80 nonelectively hospitalized for HF from 2002 to 2007.
  
  
  METHODS
  Each HRR's annual ICD/CRT-D rate was estimated from the cohort's Medicare procedure claims. Survival duration was determined from Medicare mortality records. HRR-year-level panel regression models were estimated to assess whether an HRR's ICD/CRT-D rate predicted HF survival, adjusting for baseline differences in survival across HRRs and secular trends.
  
  
  RESULTS
  A total of 883,002 HF patients were propensity-score matched within HRR across 2002 to 2007. Across HRRs, growth in ICD/CRT-D use among such patients varied from 1 to 12 percentage points. Regression models indicated that a 1 percentage point increase in an HRR's ICD/CRT-D utilization among hospitalized HF patients was associated with an increase in 1-year survival of 0.12% [95% confidence interval (CI), 0.03%-0.21%, P=0.009] and with a 0.26% increase in HF survival at 2 years (95% CI, 0.14%-0.37%, P<0.001).
  
  
  CONCLUSIONS
  Localities with greater increases in ICD/CRT-D utilization from 2002 to 2007 also had greater improvements in HF survival. Areas with persistently low ICD/CRT-D use may be good targets for programs designed to increase the evidence-based use of defibrillators.
authors.affiliation: Department of Veterans Affairs' Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Epstein
authors.forename: Daniel
authors.initials: D
authors.lastname: Polsky
authors.forename: Feifei
authors.initials: F
authors.lastname: Yang
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.forename: Peter W
authors.initials: PW
authors.lastname: Groeneveld
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058409:Cardiac Resynchronization Therapy Devices / Q000706:statistics & numerical data*; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data; D012189:Retrospective Studies; D016019:Survival Analysis; D014481:United States