title: D-dimer and factor VIII are independent risk factors for recurrence after anticoagulation withdrawal for a first idiopathic deep vein thrombosis.
abstract: OBJECTIVE
  To assess the predictive value of D-dimer (D-d) and Factor VIII (FVIII) in combination for recurrent venous thromboembolism (VTE) after vitamin K antagonist (VKA) therapy suspension.
  
  
  METHODS
  Consecutive outpatients with a first episode of idiopathic proximal deep vein thrombosis of the lower limbs were enrolled on the day of VKA suspension. After 30+/-10 days, D-d (cut-off value: 500 ng/mL), chromogenic FVIII activity and inherited thrombophilia were determined. Follow-up was 2 years.
  
  
  RESULTS
  Overall recurrence rate was 16.4% (55/336; 95% CI:13-21%). The multivariate hazard ratio (HR) for recurrence was 2.45 (95% CI: 1.24-4.99) for abnormal D-d and 2.76 (95% CI:1.57-4.85) for FVIII above the 75th percentile (2.42 U/mL) after adjustment for age, sex, thrombophilia, VKA duration and residual venous obstruction. When compared with normal D-d and FVIII, the multivariate HR was 4.5 (95% CI: 1.7-12.2) for normal D-d with FVIII above 2.42 U/mL and 2.7 (95% CI: 1.2-6.6) and 7.1 (95% CI:2.8-17.6) for abnormal D-d with FVIII, respectively, below and above 2.42 U/mL.
  
  
  CONCLUSIONS
  D-d and FVIII at 30+/-10 days after VKA withdrawal are independent risk factors for recurrent VTE.
authors.affiliation: Department of Angiology and Blood Coagulation Marino Golinelli, S. Orsola-Malpighi University Hospital, Bologna, Italy. benilde.cosmi@unibo.it
authors.forename: Benilde
authors.initials: B
authors.lastname: Cosmi
authors.forename: Cristina
authors.initials: C
authors.lastname: Legnani
authors.forename: Michela
authors.initials: M
authors.lastname: Cini
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Favaretto
authors.forename: Gualtiero
authors.initials: G
authors.lastname: Palareti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage*; D005169:Factor VIII / Q000378:metabolism*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D020246:Venous Thrombosis / Q000097:blood* / Q000188:drug therapy*; D014812:Vitamin K / Q000037:antagonists & inhibitors
chemical_list: D000925:Anticoagulants; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D; D014812:Vitamin K; D005169:Factor VIII