A multicentre randomised assessment of the DAWN AC computer-assisted oral anticoagulant dosage program

Summary

Computer-assisted oral anticoagulant dosage is being increasingly used to meet growing demands for oral anticoagulation. The DAWN AC is one of the most widely used computer-dosage programs. Evidence of its value and that of other computer programs has been based previously only on laboratory evidence of “time in target INR range” (TIR) not on clinical safety in practice. A five-year international randomised clinical study of computer assistance with the DAWN AC program compared with manual dosage in 2,631 patients has been performed at 13 centres with established expertise in oral anticoagulation mainly in the EU. Safety assessment have been based on the comparison of bleeding or thrombotic events with DAWN AC compared with manual dosage in a randomised study. Safety of the DAWN AC program has been demonstrated. Clinical events of bleeding and thrombosis were almost identical with the experienced manual dosage group. Therapeutic control improved with DAWN AC to 66.8% from 63.4% TIR. The program failed to provide a dosage recommendation on only 5.7% of occasions. At a group of experienced centres with a special interest in oral anticoagulation, the DAWN AC computer-dosage program proved as safe clinically as manual dosage by experienced medical staff. With DAWN AC, laboratory control was improved, the difference being highly significant. The results should reassure hospitals and community clinics that the DAWN AC program is safe and facilitate greater and longer provision of warfarin treatment where required.

Keywords

Computer-dosage - warfarin - clinical events - safety - DAWN AC

• References

• 1 Galagher AM, Rietbrock S, Plumb J. et al. Initiation and persistence of warfarin or aspirin in patients with chronic atrial fibrillation in general practice: do the appropriate patients receive stroke prophylaxis?. J Thromb Haemost 2008; 6: 1500-1506.
• 2 Rosendaal FR, Cannegieter SC, van der Meer FJM. et al. A method to determine the optimal intensity of oral anticoagulant therapy. Thromb Haemost 1993; 69: 236-239.
• 3 Green DG, Kelsey PR. Monitoring of anticoagulant therapy in the community using a centralised computer system with remote modules. Br J Haematol 1997; 97: 253.
• 4 Wright D, Seal J. Warfarin induction: A comparative study of laboratory-based computerised dosing versus medical staff dosing. Br J Haematol 1998; 101: 1-115.
• 5 Ageno W, Turpie AGG. A randomised comparison of a computer-based dosing program with a manual system to monitor oral anticoagulant therapy. Thromb Res 1998; 91: 237-240.
• 6 Ageno W, Johnson J, Nowacki B. et al. A computer generated induction system for hospitalized patients starting on oral anticoagulant therapy. Thromb Haemost 2000; 83: 849-852.
• 7 Mitra R, Mitra R, Marciello MA. et al. Efficacy of computer-aided dosing of warfarin among patients in a rehabilitation hospital. Am J Phys Med Rehab 2005; 84: 423-427.
• 8 Poller L, Shiach CR, MacCallum PK. et al. The European Concerted Action on Anticoagulation (ECAA). Multicentre randomised study of computerised anticoagulant dosage. Lancet 1998; 352: 1505-1509.
• 9 Poller L, Keown M, Ibrahim S. et al. An international multicentre randomised study of Computer-Assisted Oral Anticoagulant Dosage versus Medical Staff Dosage. J Thromb Haemost 2008; 6: 935-943.
• 10 Poller L, Keown M, Ibrahim S. et al. A multicentre randomised clinical end-point study of PARMA 5 computer-assisted oral anticoagulant dosage. Br J Haematol 2008; 143: 274-283.