Skip to main content

Worldwide Management of Oral Anticoagulant Therapy: the ISAM Study

Journal of Thrombosis and Thrombolysis volume 21, pages 73–77 (2006)Cite this article

Abstract

A multicenter, observational, retrospective, cross-sectional study of patients, receiving oral anticoagulation therapy (OAT) for stroke prophylaxis in chronic non-valvular atrial fibrillation (NVAF) was conducted in the US, Canada, France, Italy and Spain according to their predominant model of care [routine medical care (RMC) or Anticoagulation Clinic care (ACC)]. The study objectives were to assess anticoagulation control (time in target range), and to describe the features of the local model of care. Consecutive patients were recruited on the basis of a minimum of 60 days of oral anticoagulant treatment over a 12 month period, and clinic and physician details were captured by means of a structured face-to-face or telephone interview. Time in therapeutic range (TTR) was calculated by using linear interpolation between INR values. A total of 1511 patients were recruited, of whom 1445 were included in the analysis of TTR. TTR was higher in ACC (69.5% and 64.9% for Italy and Spain, respectively) with respect to RMC (58.1%, 62.8% and 59.3% for the US, Canada and France, respectively). Mean intervals between INR determinations were between 3 and 4 weeks. Dose changes in case of INR outside therapeutic range were more frequent in Spain and less frequent in France. Striking differences were observed in type of VKA used, specialists involved in patient management, and dosage instructions. Studying of anticoagulation management based on local models of care highlights important discrepancies among countries and suggests further standardization of the management of this important therapy is necessary.

This is a preview of subscription content, access via your institution.

Access options

Buy single article

Instant access to the full article PDF.

USD 39.95

Price includes VAT (USA)
Tax calculation will be finalised during checkout.

References

  1. Petersen P, Boysen G, Andersen Godtredsen, Andersen B. Placebo-controlled, randomized trial of warfarin and aspirin for prevention of thromboembolic complications in chronic atrial fibrillation. Lancet 1989;1:175–179.

    CAS  PubMed  Google Scholar 

  2. Atrial Fibrillation Study Group Investigators, Stroke prevention in atrial fibrillation study: Final results. Circulation 1991;84:527–539.

    Google Scholar 

  3. The Boston Area Anticoagulation Trial For Atrial Fibrillation Investigators, The effect of low-dose warfarin on the risk of stroke in patients with nonrheumatic atrial fibrillation. N Engl J Med 1990;323:1505–1511.

    Google Scholar 

  4. Connolly SJ, Laupacis A, Gent M, Roberts RS, Cairns JA, Joyner, C. Canadian atrial fibrillation study. J Am Coll Cardiol 1991;18:349–355.

    CAS  PubMed  Google Scholar 

  5. Ezekowitz SL, Bridgers KE, James NH Carliner, et al. Warfarin in the prevention of stroke associated with nonrheumatic atrial fibrillation. N Engl J Med 1992;327:1406–1412.

    CAS  PubMed  Google Scholar 

  6. European Atrial Fibrillation Trial (EAFT) Study Group. Secondary prevention in non-rheumatic atrial fibrillation after transient ischemic attack or minor stroke. Lancet 1993;342:1255–1262.

    Google Scholar 

  7. Stroke Prevention in Atrial Fibrillation Investigators. Adjusted-dose warfarin versus low-intensity, fixed-dose warfarin plus aspirin for high risk patients with atrial fibrillation: Stroke Prevention in Atrial Fibrillation III randomized clinical trial. Lancet 1996;348:633–638.

    Google Scholar 

  8. Ansell J, Hirsh J, Dalen J, et al. Managing oral anticoagulant therapy. Chest 2001;119:22S–38S.

    Article  CAS  PubMed  Google Scholar 

  9. Italian Federation of Anticoagulation Clinics. A guide to oral anticoagulant treatment. Third General Agreement. Haematologica 2003;88(suppl 2):1–52.

    Google Scholar 

  10. Van Geest-Daalderop JH, Sturk A, Levi M, Adriaansen HJ. Extent and quality of anticoagulation treatment with coumarin derivatives by the Dutch Thrombosis Services. Ned Tijdschr Geneeskd 2004;148:730–735.

    PubMed  Google Scholar 

  11. Rosendaal FR, Cannegieter SC, van der Meer FJM, Briët E. A method to determine the optimal intensity of oral anticoagulant therapy. Thromb Haemost 1993;69:236–239.

    CAS  PubMed  Google Scholar 

  12. Gadisseur AP, van der Meer FJ, Adriaansen HJ, Rosendaal FR. Therapeutic quality control of oral anticoagulant therapy comparing the short-acting acenocoumarol and the long-acting phenprocoumon. Br J Haematol 2002;117:940–946.

    Article  CAS  PubMed  Google Scholar 

  13. Penning-van Beest FJ, van Meegen E, Rosendaal FR, Stricker BH. Characteristics of anticoagulant therapy and comorbidity related to over anticoagulation. Thromb Haemost 2001;86:569–574.

    CAS  PubMed  Google Scholar 

  14. Fihn SD, Gadisseur AA, Pasterkamp E, et al. Comparison of control and stability of oral anticoagulant therapy using acenocoumarol versus phenprocoumon. Thromb Haemost 2003;90:260–266.

    CAS  PubMed  Google Scholar 

  15. Palareti G, Leali N, Coccheri S, et al. Bleeding complications of oral anticoagulant treatment: an inception-cohort, prospective collaborative study (ISCOAT). Italian Study on Complications of Oral Anticoagulant Therapy. Lancet 1996;348:423–428.

    CAS  PubMed  Google Scholar 

  16. Singer DE, Albers GW, Dalen JE, Go AS, Halperin JL, Manning WJ. Antithrombotic Therapy in Atrial Fibrillation. The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004;126:429S–456S.

    Article  CAS  PubMed  Google Scholar 

  17. Pengo V, Legnani C, Noventa F, Palareti G. Oral anticoagulant therapy in patients with nonrheumatic atrial fibrillation and risk of bleeding. Thromb Haemost 2001;85:418–422.

    CAS  PubMed  Google Scholar 

  18. van Walraven C, Hart RG, Wells GA, et al. A clinical prediction rule to identify patients with atrial fibrillation and a low risk for stroke while taking aspirin. Arch Intern Med. 2003 Apr 28;163(8):936–943.

    Google Scholar 

  19. Atrial Fibrillation Investigators (AFI). Risk factors for stroke and efficacy of antithrombotic therapy in atrial fibrillation. Analysis of pooled data from five randomised controlled trials. Arch Intern Med 1994;154(13):1449–1457.

    Google Scholar 

  20. Manotti C, Moia M, Palareti G, Pengo V, Ria L, Dettori AG. Effect of computer-aided management on the quality of treatment in anticoagulated patients: a prospective, randomized, multicenter trial of APROAT (Automated Program for Oral Anticoagulant Treatment). Haematologica 2001;86:1060–1070.

    CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Clinical Cardiology, Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua School of Medicine, Padua, 35128, Italy

    Vittorio Pengo M.D., Cinzia Pegoraro, Umberto Cucchini & Sabino Iliceto

Authors
  1. Vittorio Pengo M.D.
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Cinzia Pegoraro
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Umberto Cucchini
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Sabino Iliceto
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Vittorio Pengo M.D..

Additional information

This paper, of a presentation given at the 8th AC forum meeting, reports on the methodology, the models of care, survey results, and limited INR control data from an international study of anticoagulation management. The full analysis with respect to INR control data and other results will be provided in the final manuscript of the study.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Pengo, V., Pegoraro, C., Cucchini, U. et al. Worldwide Management of Oral Anticoagulant Therapy: the ISAM Study. J Thromb Thrombolysis 21, 73–77 (2006). https://doi.org/10.1007/s11239-006-5580-y

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11239-006-5580-y

Key Words

  • anticoagulation
  • atrial fibrillation
  • warfarin
  • vitamin k antagonists