Appropriate Use of Anticoagulation in Atrial Fibrillation Patients Dramatically Increased with Availability of Anticoagulation Management Service

Henry I. Bussey, Pharm.D., FCCP, FAHA
October, 2005

Review: Burkiewicz JS. Effect of Access to Anticoagulation Management Services on Wararin Use in Patients with Atrial Fibrillation. Pharmacotherapy 2005; 25:1062-1067.

Numerous articles have documented that almost one-half of patients with atrial fibrillation who could benefit from anticoagulation therapy do not receive such therapy as called for by established guidelines. This recent report examined the impact of having an anticoagulation management service (AMS) available to one clinic but not to another clinic within the same managed care organization.

Among atrial fibrillation patients without a contraindication to warfarin, availability of the AMS was associated with an absolute increase in anticoagulation of approximately 20% (80% vs. 60%). Among those patients aged 65 or older with an additional risk factor, the difference was even more impressive; an absolute difference of 30% (85% vs. 54%).

The increased use of anticoagulation in atrial fibrillation patients reported by Dr. Burkiewicz, together with the extensive data from trials of anticoagulation in atrial fibrillation, allow for some reasonably sound projections. Available data would indicate that such a population of atrial fibrillation patients would have a stroke rate of approximately 5% to 10% per year (depending on specific risk factors) without anticoagulation. The stroke rate can be reduced by more than 80% (on treatment analysis) with anticoagulation. If one applies these estimates to a total atrial fibrillation population of 1,000 patients, the estimated impact of having the AMS available would be the prevention of between 8 and 24 strokes per year. At an average cost of $100,000 per stroke, the AMS would be expected to reduce health care expenditures for strokes by $800,000 to $2.4 million per year. That reduction in expense alone, for a population of 1,000 patients, would be a savings of $800 to $2,400 per patient. These savings, of course, do not include savings due to lower bleeding complications and lower mortality as have been demonstrated in previous evaluations of AMS. Neither does the calculation include the potential liability that might result from lawsuits among the 20% to 30% of patients who are not treated with anticoagulation in violation of clearly recognized published guidelines.