Genetic Testing Can Help Determine a Safe Anticoagulant Dose for TJA Patients

    A 5-year, multi-center study has found that genetic testing can help surgeons choose the safest dose of the anticoagulant warfarin, with fewer side effects such as hemorrhage, for their patients undergoing joint replacement surgery.

    The study, which was published in JAMA, included nearly 1600 patients over age 65 undergoing elective hip or knee replacement at Washington University, Intermountain Medical Center, Hospital for Special Surgery in New York, University of Utah, Rush University Medical Center and the University of Texas Southwestern.

    The researchers said the findings from the Genetics InFormatics Trial (GIFT) of Warfarin to Prevent Deep Venous Thrombosis are significant. Compared with patients who received a standard dose of warfarin, patients who received a genetically guided dose had a 27% overall reduction in complications.

    Specifically, in the genetically guided warfarin group:

    • Major bleeding was reduced by 75%
    • The incidence of excessive international normalized ratios was reduced by about 30%
    • Blood clots occurred 15% less often

    No patients died during the study.

    Since 2007, language in warfarin packaging has encouraged the use of genetic guidance, if available, to individualize the dose.


    Gage BF, Bass AR, Lin H, et al. Effect of genotype-guided warfarin dosing on clinical events and anticoagulation control among patients undergoing hip or knee arthroplasty: the GIFT randomized clinical trial. JAMA. 2017; 318(12):1115-1124. doi: 10.1001/jama.2017.11469