Randomized Trial of Warfarin Nomograms
Authors: Mark A. Crowther, Linda Harrison, Jack Hirsh
Journal: Annals of Internal Medicine (2004)

Letters16 March 2004Randomized Trial of Warfarin NomogramsMark A. Crowther, MD, MSc, Linda Harrison, RN, and Jack Hirsh, MD, FCCPMark A. Crowther, MD, MScFrom McMaster University, St. Joseph's Hospital, Hamilton, Ontario L8N 4A6, Canada; Hamilton Health Sciences Corp., Hamilton, Ontario L8V 1C3, Canada; and McMaster University, Henderson Research Centre, Hamilton, Ontario L8V 1C3, Canada.Search for more papers by this author, Linda Harrison, RNFrom McMaster University, St. Joseph's Hospital, Hamilton, Ontario L8N 4A6, Canada; Hamilton Health Sciences Corp., Hamilton, Ontario L8V 1C3, Canada; and McMaster University, Henderson Research Centre, Hamilton, Ontario L8V 1C3, Canada.Search for more papers by this author, and Jack Hirsh, MD, FCCPFrom McMaster University, St. Joseph's Hospital, Hamilton, Ontario L8N 4A6, Canada; Hamilton Health Sciences Corp., Hamilton, Ontario L8V 1C3, Canada; and McMaster University, Henderson Research Centre, Hamilton, Ontario L8V 1C3, Canada.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-140-6-200403160-00027 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:The results of the study by Kovacs and colleagues (1) differ from those that we observed in 2 previous randomized trials (2, 3). In those trials, we demonstrated that a 10-mg warfarin loading dose did not hasten the achievement of a therapeutic INR but did cause more overanticoagulation (2, 3). The differences between Kovacs and colleagues' results and ours are likely to cause confusion among clinicians who have adopted a lower starting dose of warfarin.The most likely explanation for the differences in the results of our studies is patient selection. Our patients were older, were mostly ...References1. Kovacs MJ, Rodger M, Anderson DR, Morrow B, Kells G, Kovacs J, et al . Comparison of 10-mg and 5-mg warfarin initiation nomograms together with low-molecular-weight heparin for outpatient treatment of acute venous thromboembolism. A randomized, double-blind, controlled trial. Ann Intern Med. 2003;138:714-9. [PMID: 12729425] LinkGoogle Scholar2. Crowther MA, Ginsberg JB, Kearon C, Harrison L, Johnson J, Massicotte MP, et al . A randomized trial comparing 5-mg and 10-mg warfarin loading doses. Arch Intern Med. 1999;159:46-8. [PMID: 9892329] CrossrefMedlineGoogle Scholar3. Harrison L, Johnston M, Massicotte MP, Crowther M, Moffat K, Hirsh J. Comparison of 5-mg and 10-mg loading doses in initiation of warfarin therapy. Ann Intern Med. 1997;126:133-6. [PMID: 9005747] LinkGoogle Scholar4. Ageno W, Turpie AG. Exaggerated initial response to warfarin following heart valve replacement. Am J Cardiol. 1999;84:905-8. [PMID: 10532508] CrossrefMedlineGoogle Scholar Author, Article, and Disclosure InformationAuthors: Mark A. Crowther, MD, MSc; Linda Harrison, RN; Jack Hirsh, MD, FCCPAffiliations: From McMaster University, St. Joseph's Hospital, Hamilton, Ontario L8N 4A6, Canada; Hamilton Health Sciences Corp., Hamilton, Ontario L8V 1C3, Canada; and McMaster University, Henderson Research Centre, Hamilton, Ontario L8V 1C3, Canada. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoComparison of 5-mg and 10-mg Loading Doses in Initiation of Warfarin Therapy Linda Harrison , Marilyn Johnston , M. Patricia Massicotte , Mark Crowther , Karen Moffat , and Jack Hirsh Comparison of 10-mg and 5-mg Warfarin Initiation Nomograms Together with Low-Molecular-Weight Heparin for Outpatient Treatment of Acute Venous Thromboembolism Michael J. Kovacs , Marc Rodger , David R. Anderson , Beverly Morrow , Gertrude Kells , Judy Kovacs , Eleanor Boyle , and Philip S. Wells Randomized Trial of Warfarin Nomograms Theodore E. Warkentin Randomized Trial of Warfarin Nomograms Kenneth L. McCall Randomized Trial of Warfarin Nomograms Michael J. Kovacs and Philip S. Wells Randomized Trial of Warfarin Nomograms Gregory M. Peterson and Shane L. Jackson Randomized Trial of Warfarin Nomograms Richard White and William Dager Randomized Trial of Warfarin Nomograms Robert Zeller Randomized Trial of Warfarin Nomograms Brian F. Gage Randomized Trial of Warfarin Nomograms Robert J. DiDomenico Metrics Cited byA 10 mg warfarin initiation nomogram is safe and effective in outpatients starting oral anticoagulant therapy for venous thromboembolismThe risks of warfarin use in the elderlyEfficacy of Computer-Aided Dosing of Warfarin Among Patients in a Rehabilitation HospitalWarfarin Maintenance Dosing Patterns in Clinical PracticeOverview Over the Historical DevelopmentWhy Exactly has CSR Become a Necessity? 16 March 2004Volume 140, Issue 6Page: 490KeywordsDeep vein thrombosisInternational normalized ratioOutpatientsProphylaxisRandomized trials ePublished: 16 March 2004 Issue Published: 16 March 2004 Copyright & PermissionsCopyright © 2004 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...