Warfarin dosing algorithms adjust for race, assigning a fixed effect size to each predictor, thereby attenuating the differential effect by race. Attenuation likely occurs in both race groups but may be more pronounced in the less-represented race group. Therefore, we evaluated whether the effect of clinical (age, body surface area [BSA], chronic kidney disease [CKD], and amiodarone use) and ge...

OBJECTIVES To determine the incremental net health benefits of dabigatran etexilate 110 mg and 150 mg twice daily and warfarin in patients with non-valvular atrial fibrillation and to estimate the cost effectiveness of dabigatran in the United Kingdom. DESIGN Quantitative benefit-harm and economic analyses using a discrete event simulation model to extrapolate the findings of the RE-LY (Rando...

Aim To evaluate applicability of CYP2C9*2, *3 and VKORC1-1639G > A based algorithm to predict warfarin stable dose (WSD) in a group of Palestinian patients. Patients & methods Warfarin doses were retrospectively calculated for 101 Palestinian patients under warfarin therapy using three models. Performance of the three models was assessed in 47 patients found to take WSD. Results Frequency o...

Atrial fibrillation is a risk factor for stroke, particularly among elderly patients. Multiple trials have established that antithrombotic therapy decreases stroke risk. Aspirin is associated with a relative risk reduction of about 21% and adjusted-dose warfarin (international normalized ratio 2.0-3.0) is associated with a relative risk reduction of about 68%. Warfarin is more effective than as...

http://dx.doi.org/10.1160/TH14-05-0433 Thromb Haemost 2014; 112: 853–856 For the first four decades after their introduction in 1941, the clinical use of vitamin K antagonists (VKAs) was hampered by haphazard laboratory control, lack of rigorous evidence for efficacy, and bleeding complications. In this narrative historical perspective, I discuss my personal experience in providing evidence for...

BACKGROUND Vitamin K antagonists are effective in the prevention and treatment of thromboembolic disorders. Warfarin is one of the most widely prescribed vitamin K antagonists in the world [1, 2]. It has a narrow therapeutic range and a given dose may result in a large inter-individual variation of response. Insufficient dose may fail to prevent thromboembolism, while an overdose increases the ...

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to interact with the oral anticoagulant warfarin and can cause a serious bleeding complication. In this study, we evaluated the risk factors for international normalized ratio (INR) increase, which is a surrogate marker of bleeding, after addition of an NSAID in a total of 98 patients who used warfarin. Patient age, sex, body mass index, m...

BACKGROUND Warfarin, an oral anticoagulant is used in patients who are at increased risk of developing blood clots. The management of warfarin therapy is challenging because it shows large inter and intra individual variability in patient response due to factors like age, gender, diet, concurrent drug interactions and variations in CYP2C9 and VKORC1 genes. Studies implicate that polymorphisms i...

A number of a priori warfarin dosing algorithms, derived using linear regression methods, have been proposed. Although these dosing algorithms may have been validated using patients derived from the same centre, rarely have they been validated using a patient cohort recruited from another centre. In order to undertake external validation, two cohorts were utilised. One cohort formed by patients...

BACKGROUND Warfarin dosing is difficult to establish because of considerable interindividual variation. Thus, warfarin pharmacogenetics have attracted particular interest in relation to appropriate control of anticoagulation. METHODS AND RESULTS The 200 eligible subjects were chosen from participants in a hospital cohort. Performance of a pharmacogenetic algorithm recently developed by the In...