title: Implantable cardioverter defibrillator shocks are prospective predictors of anxiety.
abstract: OBJECTIVE
  To examine the temporal contingency of anxiety and implantable cardioverter defibrillator (ICD) therapy (anti-tachycardia-pacing and shocks to prevent ventricular tachycardia and/or fibrillation).
  
  
  BACKGROUND
  It is under debate whether anxiety is a precursor and/or consequence of ICD-therapy.
  
  
  METHODS
  In a prospective longitudinal study, fifty-four patients undergoing first-time ICD-implantation were assessed for anxiety, frequency of ICD-shocks and anti-tachycardia-pacing up to two days before ICD-implantation (T0) and twelve months later (T1).
  
  
  RESULTS
  Anxiety at T0 did not predict frequency of ICD-shocks at T1, but ICD-shocks significantly predicted increased anxiety at T1. In contrast, anxiety at T0 and T1 was unrelated to frequency of anti-tachycardia-pacing. Effects remained stable when we controlled for potentially confounding variables (e.g. age, sex, cardiac health and depression at T0).
  
  
  CONCLUSIONS
  Our findings indicate that repeated ICD-shocks are a cause of anxiety in ICD-patients rather than a consequence, thus shock frequency should be minimized.
authors.affiliation: Department of Psychology I, University of Würzburg, Würzburg, Germany. schulz@psychologie.uni-wuerzburg.de
authors.forename: Stefan M
authors.initials: SM
authors.lastname: Schulz
authors.forename: Claudia
authors.initials: C
authors.lastname: Massa
authors.forename: Anna
authors.initials: A
authors.lastname: Grzbiela
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Dengler
authors.forename: Georg
authors.initials: G
authors.lastname: Wiedemann
authors.forename: Paul
authors.initials: P
authors.lastname: Pauli
mesh_terms: D000328:Adult; D000368:Aged; D001007:Anxiety / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D001145:Arrhythmias, Cardiac / Q000453:epidemiology / Q000523:psychology / Q000628:therapy; D015986:Confounding Factors, Epidemiologic; D017147:Defibrillators, Implantable; D003863:Depression / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D017050:Episode of Care; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D011599:Psychopathology; D012307:Risk Factors; D013997:Time Factors