Skip to main content
Log in

Why isn’t warfarin prescribed to patients with nonrheumatic atrial fibrillation?

  • Original Articles
  • Published:
Journal of General Internal Medicine Aims and scope Submit manuscript

Abstract

OBJECTIVE: To determine the opinions of selected physicians in our community about use of warfarin for patients with nonrheumatic atrial fibrillation, and to determine the relation of the physicians’ opinions to their practices.

DESIGN: Survey of physicians, using eight hypothetical clinical vignettes to characterize physicians’ opinions about use of warfarin in patients with nonrheumatic atrial fibrillation, according to patient age, risk of bleeding, and risk of stroke.

SETTING: Two teaching hospitals and five community-based practices.

PARTICIPANTS: Eighty physicians who cared for 189 consecutive patients with nonrheumatic atrial fibrillation.

MEASUREMENTS AND MAIN RESULTS: The survey response rate was 73%. Nearly all responding physicians (90%) recommended warfarin for at least one vignette. However, physicians recommended warfarin less often for vignettes depicting 85-year-old patients than for matched vignettes depicting 65-year-old patients (odds ratio [OR] 0.03; 95% confidence interval [CI] 0.01, 0.08), and less often for cases with specified risk factors for bleeding than for matched cases without the risk factors (OR 0.01; 95% CI 0.004, 0.03); warfarin was recommended more often for cases with a recent stroke than for matched cases without this history (OR 8.2; 95% CI 3.6, 18). In practice, warfarin was prescribed more often (p<-.05) by physicians reporting good personal experience and by those who had favorable opinions about its use. However, even physicians with good experience and favorable opinions did not prescribe warfarin to half of their patents for whom warfarin was independently judged appropriate.

CONCLUSIONS: Physicians’ opinions frequently opposed warfarin for older patients with nonrheumatic atrial fibrillation, and for those with bleeding risk factors. Physicians’ opinions, as well as other barriers to warfarin therapy, most likely contribute to its infrequent prescription.

This is a preview of subscription content, log in via an institution to check access.

Access this article

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

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Petersen P, Boysen G, Godtfredsen J, Andersen ED, Andersen B. Placebo-controlled, randomised trial of warfarin and aspirin for prevention of thromboembolic complications in chronic atrial fibrillation. Lancet. 1989;1:175–9.

    Article  PubMed  CAS  Google Scholar 

  2. 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;323:1505–11.

    Article  Google Scholar 

  3. Stroke Prevention in Atrial Fibrillation Study Group Investigators. Preliminary report of the stroke prevention in atrial fibrillation study. N Engl J Med. 1990;322:863–8.

    Google Scholar 

  4. Connolly SJ, Laupacis A, Gent M, Roberts RS, Cairns JA, Joyner C. Canadian atrial fibrillation anticoagulation (CAFA) study. J Am Coll Cardiol. 1991;18:349–55.

    Article  PubMed  CAS  Google Scholar 

  5. Ezekowitz MD, Bridgers SL, James KE, et al. Warfarin in the prevention of stroke associated with nonrheumatic atrial fibrillation. N Engl J Med. 1992;327:1406–12.

    Article  PubMed  CAS  Google Scholar 

  6. Singer DE. Randomized trials of warfarin for atrial fibrillation. N Engl J Med. 1992;327:1451–3.

    Article  PubMed  CAS  Google Scholar 

  7. Albers GW, Atwood JE, Hirsh J, Sherman DG, Hughes RA, Connolly SJ. Stroke prevention in nonvalvular atrial fibrillation. Ann Intern Med. 1991;115:727–36.

    PubMed  CAS  Google Scholar 

  8. Laupacis A. Anticoagulants for atrial fibrillation. Lancet. 1993;342:1251–2.

    Article  PubMed  CAS  Google Scholar 

  9. Laupacis A, Albers G, Dunn M, Feinberg W. Antithrombotic therapy in atrial fibrillation. Chest. 1992;102:426S-33S.

    PubMed  CAS  Google Scholar 

  10. Laupacis A, Albers G, Dunn M, Feinberg W. Antithrombotic therapy in atrial fibrillation. Chest. 1995;108:352S-9S.

    PubMed  CAS  Google Scholar 

  11. Gage BF, Cardinalli AB, Albers GW, Owens DK. Cost-effectiveness of warfarin and aspirin for prophylaxis of stroke in patients with nonvalvular atrial fibrillation. JAMA. 1995;274:1839–45.

    Article  PubMed  CAS  Google Scholar 

  12. Feinberg WM, Blackshear JL, Laupacis A, Kronmal R, Hart RG. Prevalence, age distribution, and gender of patients with atrial fibrillation. Analysis and implications. Arch Intern Med. 1995;155:469–73.

    Article  PubMed  CAS  Google Scholar 

  13. Antani MR, Beyth RJ, Covinsky KE, et al. Failure to prescribe warfarin to patients with nonrheumatic atrial fibrillation. J Gen Intern Med. 1996;11:713–20.

    PubMed  CAS  Google Scholar 

  14. Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation: a major contributor to stroke in the elderly. The Framingham Study. Arch Intern Med. 1987;147:1561–4.

    Article  PubMed  CAS  Google Scholar 

  15. Atrial Fibrillation Investigators. Risk factors for stroke and efficacy of antithrombotic therapy in atrial fibrillation. Analysis of pooled data from five randomized controlled trials. Arch Intern Med. 1994;154:1449–57.

    Article  Google Scholar 

  16. Bailar JC, Louis TA, Lavori PW, Polansky M. A classification for biomedical research reports. N Engl J Med. 1984;311:1482–7.

    Article  PubMed  Google Scholar 

  17. Bath PMW, Prasad A, Brown MM, MacGregor GA. Survey of use of anticoagulation in patients with atrial fibrillation. BMJ. 1993;307:1045.

    Article  PubMed  CAS  Google Scholar 

  18. Chang HJ, Bell JR, Deroo DB, Kirk JW, Wasson JH, Dartmouth Primary Care COOP Project. Physician variation in anticoagulating patients with atrial fibrillation. Arch Intern Med. 1990;150:81–4.

    Article  Google Scholar 

  19. Kutner M, Nixon G, Silverstone F. Physicians’ attitudes toward oral anticoagulants and antiplatelet agents for stroke prevention in elderly patients with atrial fibrillation. Arch Intern Med. 1991;151:1950–3.

    Article  PubMed  CAS  Google Scholar 

  20. McCrory DC, Matchar DB, Samsa G, Sanders LL, Pritchett ELC. Physician attitudes about anticoagulation for nonvalvular atrial fibrillation. Arch Intern Med. 1995;155:277–81.

    Article  PubMed  CAS  Google Scholar 

  21. Flegel KM, Hutchinson TA, Groome PA, Tousignant P. Factors relevant to preventing embolic stroke in patients with non-rheumatic atrial fibrillation. J Clin Epidemiol. 1991;44:551–60.

    Article  PubMed  CAS  Google Scholar 

  22. Landefeld CS, Beyth RJ. Anticoagulant-related bleeding: clinical epidemiology, prediction and prevention. Am J Med. 1993;95:315–28.

    Article  PubMed  CAS  Google Scholar 

  23. Albers GW, Atrial fibrillation and stroke. Three new studies, three remaining questions. Arch Intern Med. 1994;154:1443–8.

    Article  PubMed  CAS  Google Scholar 

  24. Gurwitz JH, Avorn J, Ross-Degnan D. Aging and the anticoagulant response to warfarin therapy. Ann Intern Med. 1992;116:901–4.

    PubMed  CAS  Google Scholar 

  25. Landefeld CS, Goldman L. Major bleeding in outpatients treated with warfarin: incidence and prediction by factors known at the start of outpatient therapy. Am J Med. 1989;87:144–52.

    Article  PubMed  CAS  Google Scholar 

  26. Stroke Prevention in Atrial Fibrillation Study Group Investigators. Warfarin versus aspirin for prevention of thromboembolism in atrial fibrillation: stroke prevention in atrial fibrillation II study. Lancet. 1994;343:687–91.

    Google Scholar 

  27. Fihn SD, Callahan CM, Martin DC, McDonnell MB, Henikoff JG, White RH. The risk for and severity of bleeding complications in elderly patients treated with warfarin. Ann Intern Med. 1996;124:970–9.

    PubMed  CAS  Google Scholar 

  28. Tversky A, Kahneman D. Judgment under uncertainty: heuristics and biases. Science. 1974;185:1124–31.

    Article  PubMed  CAS  Google Scholar 

  29. Eraker SA, Politser P. How decisions are reached: physician and patient. Ann Intern Med. 1982;97:262–8.

    PubMed  CAS  Google Scholar 

  30. Spranca M, Minsk E, Baron J. Omission and commission in judgment and choice. J Exp Soc Psychol. 1991;27:76–105.

    Article  Google Scholar 

  31. Asch DA, Baron J, Hershey JC, et al. Omission bias and pertussis vaccination. Med Decis Making. 1994;14:118–23.

    Article  PubMed  CAS  Google Scholar 

  32. Wetle T. Age as a risk factor for inadequate treatment. JAMA. 1987;258:516.

    PubMed  CAS  Google Scholar 

  33. Greco PJ, Eisenberg JM. Changing physicians’ practices. N Engl J Med. 1993;329:1271–4.

    Article  PubMed  CAS  Google Scholar 

  34. Lomas J. Enkin M, Anderson GM, Hannah WJ, Vayda E, Singer J. Opinion leaders versus audit and feedback to implement practice guidelines: delivery after previous cesarean section. JAMA. 1991;265:2202–7.

    Article  PubMed  CAS  Google Scholar 

  35. Landefeld CS, Anderson PA. Guideline-based consultation to prevent anticoagulant-related bleeding: a randomized, controlled trial in a teaching hospital. Ann Intern Med. 1992;116:829–37.

    PubMed  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

Dr. Landefeld is a Senior Research Associate, Health Services Research and Development Service, Department of Veterans Affairs. Dr. Beyth is a Merck/American Federation for Aging Research Fellow in Geriatric Clinical Pharmacology. Dr. Covinsky is an awardee of the Research and Development Core, Claude D. Pepper Older Americans Independence Center, Case Western Reserve University.

Supported by an American College of Physicians’ George Morris Piersol Teaching and Research Scholarship (CSL), a John A. Hartford Foundation/American Federation for Aging Research Geriatric Pharmacology Scholarship (MRA), and by grants from the John A. Hartford Foundation (92307-G), the Case Western Reserve University Geriatric Recruitment Initiative and the National Institutes of Health (RO1 AG09657-01 and P60AG10418-03).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Beyth, R.J., Antani, M.R., Covinsky, K.E. et al. Why isn’t warfarin prescribed to patients with nonrheumatic atrial fibrillation?. J Gen Intern Med 11, 721–728 (1996). https://doi.org/10.1007/BF02598985

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02598985

Key words

Navigation