title: Symptomatic pulmonary embolism and the risk of recurrent venous thromboembolism.
abstract: BACKGROUND
  In patients with a first symptomatic pulmonary embolism (PE), the risk of recurrence is unknown. We therefore investigated the risk of recurrence among patients with spontaneous symptomatic PE and among those with deep vein thrombosis (DVT) without symptoms of PE.
  
  
  METHODS
  After discontinuation of secondary thromboprophylaxis for a first venous thromboembolism (VTE), we prospectively observed 436 patients for an average of 30 months. Patients with secondary VTE, natural inhibitor deficiencies, lupus anticoagulant, cancer, long-term antithrombotic therapy, vena cava filters, or pregnancy were excluded. The study outcome was objectively documented recurrent symptomatic VTE.
  
  
  RESULTS
  Recurrent VTE was seen among 28 (17.3%) of 162 patients with symptomatic PE and among 26 (9.5%) of 274 patients with DVT without symptoms of PE. Compared with patients with DVT, the relative risk of recurrent VTE among patients with symptomatic PE was 2.2 (95% confidence interval, 1.3-3.7; P =.005). The relative risk was not affected by age, sex, presence of factor V Leiden or prothrombin G20210A, hyperhomocysteinemia, or high factor VIII levels. Compared with patients with DVT without symptoms of PE, patients with symptomatic PE had an adjusted relative risk of PE at recurrence of 4.0 (95% confidence interval, 1.3-12.3; P =.03).
  
  
  CONCLUSIONS
  Patients with a first symptomatic PE not only have a higher risk of recurrent VTE than those with DVT without symptoms of PE, but are also at high risk of symptomatic PE at recurrence.
authors.affiliation: Division of Hematology and Hemostasis, Department of Internal Medicine I, University of Vienna, Vienna, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Eichinger
authors.forename: Ansgar
authors.initials: A
authors.lastname: Weltermann
authors.forename: Erich
authors.initials: E
authors.lastname: Minar
authors.forename: Milena
authors.initials: M
authors.lastname: Stain
authors.forename: Verena
authors.initials: V
authors.lastname: Schönauer
authors.forename: Barbara
authors.initials: B
authors.lastname: Schneider
authors.forename: Paul Alexander
authors.initials: PA
authors.lastname: Kyrle
mesh_terms: D001317:Austria / Q000453:epidemiology; D005169:Factor VIII / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000453:epidemiology*; D012008:Recurrence; D012306:Risk; D020246:Venous Thrombosis / Q000097:blood / Q000453:epidemiology*
chemical_list: D005169:Factor VIII