How you can improve TTR levels and get the best out of warfarin

Anticoagulation clinics in Primary Care

  • Use of anticoagulation clinics can improve TTR - should include routine measurement of TTR for AF patients and corrective action if the TTR is <65%1
  • Computer-assisted dosing has been shown to:2
    - improve TTR
    - reduce the frequency of testing
    - significantly reduce risk of bleeding and thromboembolic events
    - be more cost-effective than manual dosing3

Improve compliance

  • Low TTR may be due to poor compliance – assess compliance and, if necessary, adopt strategies to ensure compliance should be used4
  • The longer half-life and OD dose of warfarin could encourage compliance and provide a more consistent anticoagulant effect than products with a BD dose5



1. Connolly SJ et al. Depends on the Quality of International Normalized Ratio Control Achieved by Benefit of Oral Anticoagulant Over Antiplatelet Therapy in Atrial Fibrillation Centers and Countries as Measured by Time in Therapeutic Range. Circulation 2008; 118:2029-2037.
2. Keeling D et al. Guidelines on oral anticoagulation with warfarin – fourth edition. B J Haematol 2011 doi:10.1111/j.1365-2141.2011.08753.x.
3. Jowett S et al. The cost-effectiveness of computer-assisted anticoagulant dosage: results from the European Action on Anticoagulation (EAA) multicentre study. J Thromb Haemost 2009; 7: 1482-1490.
4. Horsley W. Dabigatran (Pradaxa®) for prevention of stroke in non-valvular atrial fibrillation. Guideline from the NHS North East Treatment Advisory Group, July 2011.
5. Gage BF. Can we rely on RE-LY? N Engl J Med 2009; 361;1200-1202.