title: The impact of gender on survival amongst patients with implantable cardioverter defibrillators for primary prevention against sudden cardiac death.
abstract: BACKGROUND
  Implantable cardioverter defibrillators (ICDs) are a life-saving therapy for many patients with cardiovascular disease at increased risk of fatal dysrhythmias. As men comprise the majority of the study population (67-92%) in clinical trials, the benefit to women is unknown. We performed a meta-analysis of primary prevention trials to evaluate the impact of ICDs in men and women on death from any cause.
  
  
  METHODS
  Included trials met the following criteria: (i) randomized controlled trials versus standard of care, (ii) ICD used as primary prevention in a well-described protocol and (iii) data provided on risk of death from any cause for both male and female patients.
  
  
  RESULTS
  Five clinical trials were included in this meta-analysis. The risk of death from any cause was significantly reduced by 26% in male patients who received ICD therapy compared to control, hazard ratio (HR) 0.74 (95% CI 0.60-0.91) but not amongst female patients, HR 0.81 (95% CI 0.60-1.09). As the COMPANION trial evaluated the combination of biventricular pacemaker with ICD therapy we conducted a separate analysis without the inclusion of this study. Male patients receiving ICD therapy demonstrated a similar 24% reduction in risk of death from any cause, HR 0.76 (95% CI 0.58-0.99) whilst female patients demonstrated a reduction of only 12%, HR 0.88 (95% CI 0.63-1.22).
  
  
  CONCLUSIONS
  Unlike their male counterparts, females did not significantly benefit from ICD therapy and without concurrent biventricular pacing, appear only to achieve a nonsignificant 12% reduction in risk of death.
authors.affiliation: University of Connecticut School of Pharmacy, Storrs and Farmington, CT, USA.
authors.forename: N N
authors.initials: NN
authors.lastname: Henyan
authors.forename: C M
authors.initials: CM
authors.lastname: White
authors.forename: E L
authors.initials: EL
authors.lastname: Gillespie
authors.forename: K
authors.initials: K
authors.lastname: Smith
authors.forename: C I
authors.initials: CI
authors.lastname: Coleman
authors.forename: J
authors.initials: J
authors.lastname: Kluger
mesh_terms: D000368:Aged; D016757:Death, Sudden, Cardiac / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011322:Primary Prevention / Q000379:methods; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D012737:Sex Factors; D016896:Treatment Outcome