title: Survival after implantable cardioverter-defibrillator implantation in the elderly.
abstract: BACKGROUND
  The benefit of implantable cardioverter-defibrillators (ICDs) among elderly patients is controversial and may be attenuated by nonarrhythmic death. We examined the impact of age on device-delivered therapies and outcomes after primary or secondary prevention ICD.
  
  
  RESULTS
  In a prospective, inclusive registry of 5399 ICD recipients in Ontario, Canada (February 2007 to September 2010), device-delivered therapies and complications were determined at routine clinic visits. Among primary prevention ICD recipients aged 18 to 49 (n=317), 50 to 59 (n=769), 60 to 69 (n=1336), 70 to 79 (n=1242), and ≥80 (n=275) years, mortality increased with age, as follows: 2.1, 3.0, 5.4, 6.9, and 10.2 deaths per 100 person-years, respectively (P<0.001). Secondary prevention ICD recipients aged 18 to 49 (n=114), 50 to 59 (n=244), 60 to 69 (n=481), 70 to 79 (n=462), and ≥80 (n=159) years also exhibited increasing mortality, as follows: 2.2, 3.8, 6.1, 8.7, and 15.5 deaths per 100 person-years, respectively (P<0.001). However, rates of appropriate shock were similar across age groups: from 6.7 (18-49 years) to 4.2 (≥80 years) per 100 person-years after primary prevention ICDs (P=0.139) and from 11.4 (18-49 years) to 11.9 (≥80 years) per 100 person-years after secondary prevention ICDs (P=0.993). Covariate-adjusted competing risk analysis demonstrated higher risk of death (Ptrend<0.001 for both primary and secondary prevention) but no significant decline in appropriate shocks with older age after primary (P=0.130) or secondary (P=0.810) prevention ICD implantation.
  
  
  CONCLUSIONS
  Whereas elderly patients exhibited increased mortality after ICD implantation, rates of appropriate device shocks were similar across age groups. Decisions regarding ICD candidacy should not be based on age alone but should consider factors that predispose to mortality despite defibrillator implantation.
authors.affiliation: University of Toronto, Toronto, ON, Canada. dlee@ices.on.ca
authors.forename: Derek
authors.initials: D
authors.lastname: Yung
authors.forename: David
authors.initials: D
authors.lastname: Birnie
authors.forename: Paul
authors.initials: P
authors.lastname: Dorian
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Healey
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Simpson
authors.forename: Eugene
authors.initials: E
authors.lastname: Crystal
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krahn
authors.forename: Yaariv
authors.initials: Y
authors.lastname: Khaykin
authors.forename: Douglas
authors.initials: D
authors.lastname: Cameron
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Chen
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000453:epidemiology / Q000401:mortality* / Q000517:prevention & control*; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D011322:Primary Prevention; D011446:Prospective Studies; D012042:Registries; D012189:Retrospective Studies; D055502:Secondary Prevention; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult
keywords: aged; defibrillators, implantabale; prognosis; prospective studies; registries