title: Venous thromboembolism in patients with implantable cardioverter-defibrillators.
abstract: OBJECTIVE
  To examine the incidence of venous thromboembolism (VTE) and its risk factors among patients with implantable cardioverter-defibrillators (ICDs).
  
  
  RESULTS
  All first-time ICD recipients in Denmark during 2000-12 were identified from medical databases. Incident VTEs were ascertained, overall and according to gender, age, Charlson Comorbidity Index score (no, moderate, or severe comorbidity), prior pacemaker or cardiac resynchronization therapy (CRT-D) implantation, and ICD type (single-chamber, dual-chamber, or CRT-D). We computed the risk of VTE within 3 months and 5 years of implantation, taking death into account as a competing risk. We used Cox proportional hazards regression to compute hazard ratios as estimates of incidence rate ratios (IRRs). Among 8132 ICD recipients, 136 VTEs were diagnosed during up to 13 years of follow-up (median = 3.0 years). The VTE incidence rate was thus 4.5 per 1000 person-years [95% confidence interval (CI): 3.7-5.2]. Venous thromboembolism risk was 0.3% (95% CIs ranging from 0.1 to 0.7%) within 3 months following ICD implantation regardless of comorbidity level. Within 5 years following implantation it was 1.4% (95% CI: 0.8-2.3%), 1.3% (1.0-1.8%), and 3.2% (95% CI: 2.4-4.1%) for patients with no, moderate, and severe comorbidity, respectively. Overall, severe comorbidity conferred a 2.7-fold higher incidence rate ratio than no comorbidity (95% CI: 1.6-4.6). Incidence rate ratios did not differ by gender, age, or ICD type.
  
  
  CONCLUSIONS
  Three-month risk of VTE following ICD implantation was 0.3% regardless of comorbidity level. Five-year risk of VTE following ICD implantation was 1.9% and more than twice as high for patients with severe comorbidity as for patients without comorbidity.
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.|Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200 Aarhus N, Denmark.
authors.forename: Susanne Bendesgaard
authors.initials: SB
authors.lastname: Pedersen
authors.affiliation: Department of Cardiology, Aalborg University Hospital, Hobrovej 18-22, 9100 Aalborg, Denmark.
authors.forename: Søren Pihlkjær
authors.initials: SP
authors.lastname: Hjortshøj
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
authors.forename: Hans Erik
authors.initials: HE
authors.lastname: Bøtker
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200 Aarhus N, Denmark.
authors.forename: Dóra Körmendiné
authors.initials: DK
authors.lastname: Farkas
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.|Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200 Aarhus N, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200 Aarhus N, Denmark.
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
authors.forename: Jens Cosedis
authors.initials: JC
authors.lastname: Nielsen
mesh_terms: D000367:Age Factors; D000368:Aged; D015897:Comorbidity; D016208:Databases, Factual; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D003718:Denmark / Q000453:epidemiology; D004554:Electric Countershock / Q000009:adverse effects* / Q000295:instrumentation*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D012042:Registries; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000175:diagnosis / Q000453:epidemiology*
keywords: Epidemiology; Implantable cardioverter-defibrillator; Incidence; Risk factor; Venous thromboembolism