title: Predictors of mortality in patients with an implantable cardiac defibrillator: a systematic review and meta-analysis.
abstract: BACKGROUND
  Many current predictors of mortality in heart failure (HF) were evaluated before the use of implantable cardioverter defibrillators (ICDs). We conducted a meta-analysis to identify factors associated with mortality in ICD-HF patients.
  
  
  METHODS
  We searched in MedLine, EMBASE, and CINAHL in May 2012. Two reviewers selected citations that included ambulatory ICD patients and addressed the association between any predictor and mortality using multivariable regression. We meta-analyzed mortality using random-effects models.
  
  
  RESULTS
  Of 10,420 studies reviewed, 72 studies evaluating 63 predictors on 257,692 ICD patients proved eligible. High confidence in estimates was found for age (hazard ratio [HR], 1.45 for 10-year increase; 95% confidence interval [CI], 1.35-1.56), baseline glomerular filtration rate (HR, 1.25 for 15-mL/min decrease; 95% CI, 1.15-1.35), chronic obstructive pulmonary disease (HR, 1.54; 95% CI, 1.38-1.71), diabetes (HR, 1.56; 95% CI, 1.37-1.79), peripheral vascular disease (HR, 1.43; 95% CI, 1.2-1.72), left ventricular ejection fraction (HR, 0.77 for 10% increase; 95% CI, 0.73-0.83), and appropriate or inappropriate ICD shocks (HR, 2.34; 95% CI 1.59-3.44) New York Heart Association class, atrial fibrillation, and congestive HF were strongly associated with mortality but the confidence in estimates was low. Ischemic cardiomyopathy and male sex were not independent predictors of mortality.
  
  
  CONCLUSIONS
  This meta-analysis identified strong reliable mortality predictors in ICD-HF patients. Age, renal dysfunction, chronic obstructive pulmonary disease, diabetes, peripheral vascular disease, decreased left ventricular ejection fraction, and ICD shocks during follow-up were strong predictors of mortality; ischemic cardiomyopathy and male sex were not. Further research is needed to study other potential predictors, particularly biomarkers.
authors.affiliation: Heart Failure/Transplant Program, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada. Electronic address: carolina.alba@uhn.ca.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Alba
authors.forename: Juarez
authors.initials: J
authors.lastname: Braga
authors.forename: Mena
authors.initials: M
authors.lastname: Gewarges
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Walter
authors.forename: Gordon H
authors.initials: GH
authors.lastname: Guyatt
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Ross
mesh_terms: D000368:Aged; D002423:Cause of Death; D015897:Comorbidity; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012044:Regression Analysis; D012307:Risk Factors