SEARCH:   Advanced

Blood, 15 March 2007, Vol. 109, No. 6, pp. 2419-2423. Prepublished online as a Blood First Edition Paper on November 16, 2006; DOI 10.1182/blood-2006-09-049262. This Article Full Text Full Text (PDF) All Versions of this Article: blood-2006-09-049262v1 109/6/2419    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Sconce, E. Articles by Kamali, F. Search for Related Content PubMed PubMed Citation Articles by Sconce, E. Articles by Kamali, F. Related Collections Hemostasis, Thrombosis, and Vascular Biology Clinical Trials and Observations Social Bookmarking                   What's this?  Previous Article  |  Table of Contents  |  Next Article  HEMOSTASIS, THROMBOSIS, AND VASCULAR BIOLOGY Vitamin K supplementation can improve stability of anticoagulation for patients with unexplained variability in response to warfarin Elizabeth Sconce1, Peter Avery2, Hilary Wynne3, and Farhad Kamali1 1 School of Clinical and Laboratory Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom; 2 School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, United Kingdom; 3 Care of the Elderly, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom Patients receiving warfarin who have unstable control of anticoagulation have a significantly lower intake of dietary vitamin K compared with their stable counterparts. We hypothesized that supplementation with oral vitamin K would improve stability in patients with previously unstable control of anticoagulation. Seventy warfarin-treated patients with unstable anticoagulation control were randomly assigned in a double-blinded fashion to receive a daily amount of 150 µg oral vitamin K or placebo orally for 6 months. Measures of stability of anticoagulation control in the 6-month study period were compared with those in the 6 months immediately prior to it. Vitamin K supplementation resulted in a significantly greater decrease in standard deviation of international normalized ratio (INR) compared with placebo (–0.24 ± 0.14 vs –0.11 ± 0.18; P < .001) and a significantly greater increase in percentage time within target INR range (28% ± 20% vs 15% ± 20%; P < .01). Anticoagulation control improved in 33 of 35 patients receiving vitamin K supplementation; of these, 19 fulfilled our criteria for having stable control of anticoagulation. However, only 24 of 33 patients receiving placebo demonstrated some degree of improvement, with only 7 patients fulfilling the criteria for having stable control. Concomitant supplementation of vitamin K, perhaps through reducing the relative day-to-day variability in dietary vitamin K intake, can significantly improve anticoagulation control in patients with unexplained instability of response to warfarin. CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? This article has been cited by other articles: M. C. de Assis, E. R. Rabelo, C. W. Avila, C. A. Polanczyk, and L. E. Rohde Improved Oral Anticoagulation After a Dietary Vitamin K-Guided Strategy: A Randomized Controlled Trial Circulation, September 22, 2009; 120(12): 1115 - 1122. [Abstract] [Full Text] [PDF] C. E. Janeczko, K. Sweeney, and G Connaghan Supplemental vitamin K improves the stability of anticoagulation in a patient with low tissue stores of vitamin K secondary to coeliac disease BMJ Case Reports, May 17, 2009; 2009(may17_1): bcr1020081067 - bcr1020081067. [Abstract] [Full Text] J. Ansell, J. Hirsh, E. Hylek, A. Jacobson, M. Crowther, and G. Palareti Pharmacology and Management of the Vitamin K Antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition) Chest, June 1, 2008; 133(6_suppl): 160S - 198S. [Abstract] [Full Text] [PDF] S. Moll A Clinical Perspective of Venous Thromboembolism Arterioscler Thromb Vasc Biol, March 1, 2008; 28(3): 373 - 379. [Full Text] [PDF] R. L. Silverstein, K. A. Bauer, M. Cushman, C. T. Esmon, W. B. Ershler, and R. P. Tracy Venous thrombosis in the elderly: more questions than answers Blood, November 1, 2007; 110(9): 3097 - 3101. [Full Text] [PDF] E. Sconce, H. Wynne, and F. Kamali Vitamin K supplementation during oral anticoagulation: no real cause for concern Blood, April 15, 2007; 109(8): 3607 - 3607. [Full Text] [PDF] E. Sconce, H. Wynne, and F. Kamali Response: vitamin K supplementation during oral anticoagulation: no real cause for concern Blood, April 15, 2007; 109(8): 3607 - 3608. [Full Text] [PDF]

	Copyright © 2007 by American Society of Hematology         Online ISSN: 1528-0020