AIMS Although genetic, clinical and demographic factors have been shown to explain approximately half of the inter-individual variability in warfarin dose requirement in adults, less is known about causes of dose variability in children. This study aimed to identify and quantify major genetic, clinical and demographic sources of warfarin dose variability in children using modelling and simulati...

The question of whether or not combination antithrombotic therapy is beneficial in terms of a reduction in fatal and non-fatal vascular events in atrial fibrillation (AF) is an important question which essentially remains unanswered. Original randomised controlled trials in AF patients examining the efficacy of combination oral anticoagulant (OAC) and antiplatelet therapy for stroke prevention ...

INTRODUCTION Vitamin K antagonists of the coumarin type are widely used oral anticoagulants. OBJECTIVE We developed a transition algorithm for the maintenance dosages of three frequently used coumarins: warfarin, phenprocoumon and acenocoumarol. METHODS The study was conducted at the Leiden Anticoagulation Clinic. Patients were participants in a trial of which the main objective was to comp...

OBJECTIVE DNA biobanks linked to comprehensive electronic health records systems are potentially powerful resources for pharmacogenetic studies. This study sought to develop natural-language-processing algorithms to extract drug-dose information from clinical text, and to assess the capabilities of such tools to automate the data-extraction process for pharmacogenetic studies. MATERIALS AND M...

Multiple factors have been shown to influence the pharmacokinetics, pharmacodynamics and, hence, dosage requirements of the oral anticoagulant, warfarin (1-3). The relationship between patient age in the adult population and warfarin maintenance dose is controversial. Several studies (4-6) have found a significant inverse correlation between age and dose, and it has been reported (5) that the e...

We are presenting a 72-year-old female who was admitted to hospital with deep vein thrombosis (DVT). She was known to have atrial fibrillation and was initiated on warfarin for stroke prophylaxis 3 days earlier. She was given warfarin therapy without low molecular weight heparin cover as per "slow-start regimen" protocol. The warfarin dose was increased after 3 days to achieve rapid anticoagula...

Candidates for chronic warfarin therapy often have co-morbid conditions, such as heart failure, with reduced left ventricular ejection fraction. Previous reports have demonstrated an increased risk of over-anticoagulation due to reduced warfarin dose requirement in patients with decompensated heart failure. However, the influence of left ventricular systolic dysfunction (LVSD), defined as left ...

OBJECTIVES Warfarin is a commonly prescribed anticoagulant drug used to prevent thromboses that may arise as a consequence of orthopedic and vascular surgery or underlying cardiovascular disease. Warfarin is associated with a notoriously narrow therapeutic window where small variations in dosing may result in hemorrhagic or thrombotic complications. To ultimately improve dosing of warfarin, we ...

A prospective study was carried out to see whether a small fixed dose of warfarin (1 mg daily) given before operation (mean 20 days) would prevent deep vein thrombosis in patients having major gynaecological surgery. One hundred and four patients were randomised into three groups: fixed minidose warfarin; full dose oral anticoagulation; and no treatment (controls). There was a significantly low...