The cost-effectiveness of different management strategies for patients on chronic warfarin therapy Authors
10.1046/j.1525-1497.2000.01239.x Cite this article as: Lafata, J.E., Martin, S.A., Kaatz, S. et al. J GEN INTERN MED (2000) 15: 31. doi:10.1046/j.1525-1497.2000.01239.x
OBJECTIVE: To examine the cost-effectiveness of moving from usual care to more organized management strategies for patients on chronic warfarin therapy.
DESIGN: Using information available in the scientific literature, supplemented with data from a large health system and, when necessary, expert opinion, we constructed a 5-year Markov model to evaluate the health and economic outcomes associated with each of three different anticoagulation management approaches: usual care, anticoagulation clinic testing with a capillary monitor, and patient self-testing with a capillary monitor.
PATIENTS: Three hypothetical cohorts of patients beginning long-term warfarin therapy were used to generate model results.
MAIN RESULTS: Model results indicated that moving from usual care to anticoagulation clinic testing would result in a total of 1.7 thromboembolic events and 2.0 hemorrhagic events avoided per 100 patients over 5 years. Another 4.0 thromboembolic events and 0.8 hemorrhagic events would be avoided by moving to patient self-testing. When direct medical care costs and those incurred by patients and their caregivers in receiving care were considered, patient self-testing was the most cost-effective alternative, resulting in an overall cost saving.
CONCLUSIONS: Results illustrate the potential health and economic benefits of organized care management approaches and capillary monitors in the management of patients receiving warfarin therapy.
decision analytic model
Presented at the Society of General Internal Medicine 21st annual meeting, Chicago, Il, April 23–25, 1998; Building Bridges IV: Improving the Public’s Health Through Research Partnerships, Oakland, Calif, May 7–9, 1998; Association for Health Services Research, Washington, DC, June 21–23, 1998; European Cardiology Conference, Vienna, Austria, August 24–28, 1998; and Anticoagulation Forum’s 5th annual conference, Vancouver, BC, May 13–15, 1999.
Financial support for this work was received from Boehringer Mannheim Corp.
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