title: Index clinical manifestation of venous thromboembolism predicts early recurrence type and frequency: a meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Observational studies suggest index clinical manifestation of venous thromboembolism (VTE) predicts recurrence type. Data regarding the association between index manifestation and recurrence rates are conflicting.
  
  
  OBJECTIVE
  To perform a meta-analysis of randomized controlled trials (RCTs) to determine the type and frequency of recurrent VTE (rVTE) in persons after an index deep vein thrombosis (DVT) or pulmonary embolism (PE).
  
  
  METHODS
  We searched bibliographic databases for RCTs of acute (early) treatment of rVTE in persons with an index DVT or PE (±DVT), enrolling ≥ 50 subjects anticoagulated ≥ 3-months and reporting types of rVTE. We pooled (random-effects) the proportion of rVTEs that were DVTs, PEs, and fatal PEs, the proportion of recurrent PEs that were fatal, and absolute rVTE rates.
  
  
  RESULTS
  In nine RCTs (N = 13 640; 413 rVTEs) evaluating persons with an index PE; 66% (95% CI, 60-72%) of rVTEs were PE and 27% (95% CI, 22-33%) were fatal PE. Among 25 RCTs (N = 17 340; 692 rVTEs) evaluating persons with an index DVT, 36% (95% CI, 29-44%) experienced a recurrent PE and 10% (95% CI, 7-13%) a fatal PE. Recurrent PEs following an index PE had a higher fatality rate than after an index DVT (41%; 95% CI, 33-48% vs. 25%; 95% CI, 18-33%; P = 0.007). The rVTE rate was higher following an index DVT compared with a PE (2.6%; 95% CI, 1.6-3.8% vs. 4.9%; 95% CI, 4.0-6.0%; P = 0.002).
  
  
  CONCLUSIONS
  Our meta-analysis suggests most rVTEs will be the same type as the index event. While index DVTs are associated with a higher rVTE rate than index PEs; recurrent PEs are associated with high fatality.
authors.affiliation: Department of Pharmacy Practice, University of Connecticut School of Pharmacy, Storrs, CT, USA.|University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.
authors.forename: E S
authors.initials: ES
authors.lastname: Mearns
authors.affiliation: Department of Pharmacy Practice, University of Connecticut School of Pharmacy, Storrs, CT, USA.|University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.
authors.forename: C I
authors.initials: CI
authors.lastname: Coleman
authors.affiliation: Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, USA.
authors.forename: D
authors.initials: D
authors.lastname: Patel
authors.affiliation: Department of Pharmacy Practice, University of Connecticut School of Pharmacy, Storrs, CT, USA.|University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Saulsberry
authors.affiliation: University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.
authors.forename: A
authors.initials: A
authors.lastname: Corman
authors.affiliation: University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.
authors.forename: D
authors.initials: D
authors.lastname: Li
authors.affiliation: Health Outcomes and Clinical Epidemiology Section, Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.|Postgraduate and Medical Schools, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru.
authors.forename: A V
authors.initials: AV
authors.lastname: Hernandez
authors.affiliation: University of Connecticut/Hartford Hospital Evidence-Based Practice Center, Hartford, CT, USA.|Department of Pharmacy Practice and Administration, University of Saint Joseph School of Pharmacy, Hartford, CT, USA.
authors.forename: C G
authors.initials: CG
authors.lastname: Kohn
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use; D006801:Humans; D011237:Predictive Value of Tests; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality; D016032:Randomized Controlled Trials as Topic; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality; D020246:Venous Thrombosis / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality
chemical_list: D000925:Anticoagulants
keywords: deep vein thrombosis; meta-analysis; pulmonary embolism; venous thromboembolism; venous thrombosis