title: Duration of anticoagulation for the management of venous thromboembolism in inflammatory bowel disease: a decision analysis.
abstract: OBJECTIVE
  There is practice variation in the duration of anticoagulation for venous thromboembolism (VTE) in inflammatory bowel disease (IBD) patients. Clinicians must weigh the high risk of recurrent VTE with the risk of gastrointestinal bleeding.
  
  
  METHODS
  We implemented Markov decision analysis to compare the costs and effectiveness of extended anticoagulation vs. time-limited anticoagulation (6 months) among IBD patients with first unprovoked VTE over a 5-year time horizon. In a secondary analysis, we added two strategies in which therapeutic-dose or prophylactic-dose anticoagulation was administered during IBD flares.
  
  
  RESULTS
  Compared with time-limited anticoagulation, extended anticoagulation yielded slightly higher quality-adjusted life years (QALYs) (4.40 vs. 4.38) and costs ($21,158 vs. $20,825), and an incremental cost-effectiveness ratio (ICER) of $15,254/QALY over 5 years. In secondary analysis, pharmacological prophylaxis during IBD flares was associated with the highest QALYs (4.41) and costs ($28,177), but was not cost-effective when compared with extended anticoagulation (ICER=$1,158,717/QALY). Anticoagulation during flares yielded the lowest cost ($19,681) and same QALYs as extended anticoagulation. In probabilistic sensitivity analysis, extended anticoagulation yielded higher QALYs than time-limited anticoagulation in 91% of trials and was dominant or cost-effective (<$50,000/QALY) in 72% of trials. When analyzed over a lifetime, extended anticoagulation dominated time-limited anticoagulation with higher effectiveness (18.44 vs. 17.95 QALYs) and lower costs ($94,738 vs. $102,874) and was highly robust in sensitivity analyses.
  
  
  CONCLUSIONS
  Our analyses suggest that extended anticoagulation may provide marginal benefit over time-limited anticoagulation and should be considered in the management of first unprovoked VTE in IBD. Anticoagulation and prophylaxis during IBD flares are alternative viable strategies.
authors.affiliation: Mount Sinai Hospital Centre for Inflammatory Bowel Disease, University of Toronto, Toronto, Ontario, Canada. geoff.nguyen@utoronto.ca
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Nguyen
authors.forename: Charles N
authors.initials: CN
authors.lastname: Bernstein
mesh_terms: D000925:Anticoagulants / Q000009:adverse effects / Q000191:economics / Q000627:therapeutic use*; D003657:Decision Making; D003661:Decision Support Techniques; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications* / Q000191:economics; D008297:Male; D019057:Quality-Adjusted Life Years; D012306:Risk; D054556:Venous Thromboembolism / Q000150:complications / Q000188:drug therapy*
chemical_list: D000925:Anticoagulants