Clinical and genetic factors influencing acenocoumarol dosing

: Coumadin oral anticoagulants are widely used in multiple clinical scenarios. Their narrow therapeutic range and a dosing strategy based on 'a posteriori' algorithms, pose them as an interesting group for prediction modelling research. Extensive literature explaining the association between clinical and genetic variables with the dose of warfarin have been published. Limited information exists regarding these factors and acenocoumarol dosing. The aim of the study is to explain through clinical/genetic variables, the weekly dose of acenocoumarol necessary for achieving stable anticoagulation status. We performed a cross-sectional study enrolling adults under treatment with acenocoumarol with at least three consecutive INRs between 2 and 3. To explain the association between demographic, clinical and genotype data (VKORC1, CYP2C9 and CYP4F2) and the mean weekly dose of acenocoumarol, we performed a multiple linear regression model. In our cohort, a higher age, the presence of atrial fibrillation, chronic renal failure and VKORC1 haplotype A were associated with a lower mean weekly dose of acenocoumarol. On the other side, a higher weight was associated with a higher weekly dose. Amongst anticoagulated adult patients, VKORC1 genotype and baseline clinical factors can explain acenocoumarol dosing, and therefore, help clinicians while deciding the initial anticoagulant dose.