title: Cardiac resynchronization therapy reduces the risk of hospitalizations in patients with advanced heart failure: results from the Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure (COMPANION) trial.
abstract: BACKGROUND
  In the Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure (COMPANION) trial, 1520 patients with advanced heart failure were assigned in a 1:2:2 ratio to optimal pharmacological therapy or optimal pharmacological therapy plus cardiac resynchronization therapy (CRT-P) or CRT with defibrillator (CRT-D). Use of CRT-P and CRT-D was associated with a significant reduction in combined risk of death or all-cause hospitalizations. Because mortality also was significantly reduced (optimal pharmacological therapy versus CRT-D only), an assessment of the true reduction in hospitalization rates must consider the competing risk of death and varying follow-up times.
  
  
  RESULTS
  To overcome the challenges of comparing treatment groups, we used a nonparametric test of right-censored recurrent events that accounts for multiple hospital admissions, differential follow-up time between treatment groups, and death as a competing risk. An end-point committee adjudicated and classified all hospitalizations. Compared with optimal pharmacological therapy, CRT-P and CRT-D were associated with a 21% and 25% reduction in all-cause, 34% and 37% reduction in cardiac, and 44% and 41% reduction in heart failure hospital admissions per patient-year of follow-up, respectively. Similar reductions were seen in hospitalization days per patient-year. The reduction in hospitalization rate for heart failure in the CRT groups appeared within days of randomization and remained sustained. Noncardiac hospitalization rates were not different between groups.
  
  
  CONCLUSIONS
  Use of CRT with or without a defibrillator in advanced heart failure patients was associated with marked reductions in all-cause, cardiac, and heart failure hospitalization rates in an analysis that accounted for the competing risk of mortality and unequal follow-up time.
authors.affiliation: Division of Cardiology 111-C, Veterans Affairs Medical Center, 1 Veterans Drive, Minneapolis, MN 55417, USA. anand001@umn.edu
authors.forename: Inder S
authors.initials: IS
authors.lastname: Anand
authors.forename: Peter
authors.initials: P
authors.lastname: Carson
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Galle
authors.forename: Rui
authors.initials: R
authors.lastname: Song
authors.forename: John
authors.initials: J
authors.lastname: Boehmer
authors.forename: Jalal K
authors.initials: JK
authors.lastname: Ghali
authors.forename: Brian
authors.initials: B
authors.lastname: Jaski
authors.forename: JoAnn
authors.initials: J
authors.lastname: Lindenfeld
authors.forename: Christopher
authors.initials: C
authors.lastname: O'Connor
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Steinberg
authors.forename: Jill
authors.initials: J
authors.lastname: Leigh
authors.forename: Patrick
authors.initials: P
authors.lastname: Yong
authors.forename: Michael R
authors.initials: MR
authors.lastname: Kosorok
authors.forename: Arthur M
authors.initials: AM
authors.lastname: Feldman
authors.forename: David
authors.initials: D
authors.lastname: DeMets
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bristow
mesh_terms: D000328:Adult; D000368:Aged; D002304:Cardiac Pacing, Artificial; D017147:Defibrillators, Implantable; D005260:Female; D006333:Heart Failure / Q000628:therapy*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged