title: Age and sex differences in long-term outcomes following implantable cardioverter-defibrillator placement in contemporary clinical practice: findings from the Cardiovascular Research Network.
abstract: BACKGROUND
  Patient sex and age may influence rates of death after receiving an implantable cardioverter-defibrillator for primary prevention. Differences in outcomes other than mortality and whether these differences vary by heart failure symptoms, etiology, and left ventricular ejection fraction are not well characterized.
  
  
  RESULTS
  We studied 2954 patients with left ventricular ejection fraction ≤0.35 undergoing first-time implantable cardioverter-defibrillator for primary prevention within the Cardiovascular Research Network; 769 patients (26%) were women, and 2827 (62%) were aged >65 years. In a median follow-up of 2.4 years, outcome rates per 1000 patient-years were 109 for death, 438 for hospitalization, and 111 for heart failure hospitalizations. Procedure-related complications occurred in 8.36%. In multivariable models, women had significantly lower risks of death (hazard ratio 0.67, 95% CI 0.56 to 0.80) and heart failure hospitalization (hazard ratio 0.82, 95% CI 0.68 to 0.98) and higher risks for complications (hazard ratio 1.38, 95% CI 1.01 to 1.90) than men; patients aged >65 years had higher risks of death (hazard ratio 1.55, 95% CI 1.30 to 1.86) and heart failure hospitalization (hazard ratio 1.25, 95% CI 1.05 to 1.49) than younger patients. Age and sex differences were generally consistent in strata according to symptoms, etiology, and severity of left ventricular systolic dysfunction, except the higher risk of complications in women, which differed by New York Heart Association classification (P=0.03 for sex-New York Heart Association interaction), and the risk of heart failure hospitalization in older patients, which differed by etiology of heart failure (P=0.05 for age-etiology interaction).
  
  
  CONCLUSIONS
  The burden of adverse outcomes after receipt of an implantable cardioverter-defibrillator for primary prevention is substantial and varies according to patient age and sex. These differences in outcome generally do not vary according to baseline heart failure characteristics.
authors.affiliation: University of Colorado Anschutz Medical Campus, Aurora, CO (F.A.M., D.J.M., P.N.P.) Institute for Health Research, Kaiser Permanente Colorado, Denver, CO (F.A.M., D.J.M., L.M.R., K.A.G., P.N.P.).
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Masoudi
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, CA (A.S.G.) Departments of Epidemiology, Biostatistics and Medicine, University of California, San Francisco, CA (A.S.G.).
authors.forename: Alan S
authors.initials: AS
authors.lastname: Go
authors.affiliation: University of Colorado Anschutz Medical Campus, Aurora, CO (F.A.M., D.J.M., P.N.P.) Institute for Health Research, Kaiser Permanente Colorado, Denver, CO (F.A.M., D.J.M., L.M.R., K.A.G., P.N.P.).
authors.forename: David J
authors.initials: DJ
authors.lastname: Magid
authors.affiliation: Department of Public Health Sciences, Henry Ford Hospital, Detroit, MI (A.E.C.B.).
authors.forename: Andrea E
authors.initials: AE
authors.lastname: Cassidy-Bushrow
authors.affiliation: Meyers Primary Care Institute, Worcester, MA (J.H.G., R.G.) University of Massachusetts Medical School, Worcester, MA (J.H.G., R.G.).
authors.forename: Jerry H
authors.initials: JH
authors.lastname: Gurwitz
authors.affiliation: Department of Cardiac Electrophysiology, Kaiser Permanente Northern California, Santa Clara, CA (T.I.L.).
authors.forename: Taylor I
authors.initials: TI
authors.lastname: Liu
authors.affiliation: Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA (K.R.).
authors.forename: Kristi
authors.initials: K
authors.lastname: Reynolds
authors.affiliation: Center for Health Research, Kaiser Permanente Northwest, Portland, OR (D.H.S.).
authors.forename: David H
authors.initials: DH
authors.lastname: Smith
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado, Denver, CO (F.A.M., D.J.M., L.M.R., K.A.G., P.N.P.).
authors.forename: Liza M
authors.initials: LM
authors.lastname: Reifler
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado, Denver, CO (F.A.M., D.J.M., L.M.R., K.A.G., P.N.P.).
authors.forename: Karen A
authors.initials: KA
authors.lastname: Glenn
authors.affiliation: American College of Cardiology Foundation, Washington, DC (F.F.).
authors.forename: Frances
authors.initials: F
authors.lastname: Fiocchi
authors.affiliation: Meyers Primary Care Institute, Worcester, MA (J.H.G., R.G.) University of Massachusetts Medical School, Worcester, MA (J.H.G., R.G.).
authors.forename: Robert
authors.initials: R
authors.lastname: Goldberg
authors.affiliation: Kaiser Permanente, Los Angeles Medical Center, Los Angeles, CA (N.G.).
authors.forename: Nigel
authors.initials: N
authors.lastname: Gupta
authors.affiliation: University of Colorado Anschutz Medical Campus, Aurora, CO (F.A.M., D.J.M., P.N.P.) Institute for Health Research, Kaiser Permanente Colorado, Denver, CO (F.A.M., D.J.M., L.M.R., K.A.G., P.N.P.) Denver Health Medical Center, Denver, CO (P.N.P.).
authors.forename: Pamela N
authors.initials: PN
authors.lastname: Peterson
authors.affiliation: Henry Ford Hospital Heart and Vascular Institute, Detroit, MI (C.S.).
authors.forename: Claudio
authors.initials: C
authors.lastname: Schuger
authors.affiliation: Marshfield Clinic, Marshfield, WI (H.V.).
authors.forename: Humberto
authors.initials: H
authors.lastname: Vidaillet
authors.affiliation: Mayo Clinic, Rochester, MN (S.C.H.).
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hammill
authors.affiliation: Marshfield Clinic Research Foundation, Marshfield, WI (R.T.G.).
authors.forename: Robert T
authors.initials: RT
authors.lastname: Greenlee
mesh_terms: D000367:Age Factors; D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality / Q000601:surgery; D017147:Defibrillators, Implantable / Q000009:adverse effects / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000401:mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000401:mortality / Q000706:statistics & numerical data; D012307:Risk Factors; D012737:Sex Factors; D014481:United States / Q000453:epidemiology
keywords: elderly; implanted cardioverter‐defibrillator; prognosis; women