Warfarin genotyping reduces hospitalization rates

January 01, 0001

Warfarin genotyping reduces hospitalization rates

This study was designed to determine whether genotype testing for patients initiating warfarin treatment will reduce the incidence of hospitalizations, including those due to bleeding or thromboembolism. Genotypic variations in CYP2C9 and VKORC1 have been shown to predict warfarin dosing, but no large-scale studies have prospectively evaluated the clinical effectiveness of genotyping in naturalistic settings across the U.S. This national, prospective, comparative effectiveness study compared the 6-month incidence of hospitalization in patients receiving warfarin genotyping (n = 896) versus a matched historical control group (n = 2,688). To evaluate for temporal changes in the outcomes of warfarin treatment, a secondary analysis compared outcomes for 2 external control groups drawn from the same 2 time periods.

Compared with the historical control group, the genotyped cohort had 31% fewer hospitalizations overall (adjusted hazard ratio HR: 0.69, significant) and 28% fewer hospitalizations for bleeding or thromboembolism (HR: 0.72, significant) during the 6-month follow-up period. Findings from a per-protocol analysis were even stronger: 33% lower risk of all-cause hospitalization (HR: 0.67, significant) and 43% lower risk of hospitalization for bleeding or thromboembolism (HR: 0.57, significant) in patients who were genotyped. During the same period, there was no difference in outcomes between the 2 external control groups.

The researchers concluded: "Warfarin genotyping reduced the risk of hospitalization in outpatients initiating warfarin."

More benefits of genotyping. The use of this testing maybe dependant on costs, but the cost-savings would appear to be impressive.

For the full abstract, click here.

J Am Coll Cardiol published online 30 March 2010 55:2804-2812
© 2010 by the American College of Cardiology
Warfarin Genotyping Reduces Hospitalization Rates Results From the MM-WES (Medco-Mayo Warfarin Effectiveness Study). Robert S. Epstein, Thomas P. Moyer, Ronald E. Aubert et al. Correspondence to Robert Epstein: [email protected]

Category: B. Blood/Blood Forming Organs/Immune Mechanisms. Keywords: warfarin, genotyping, pharmacogenomics, comparative effectiveness, journal watch.
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 2 July 2010

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.