Influence of age on the prescription of vitamin K antagonists in outpatients with permanent atrial fibrillation in France.

International audiencePURPOSE: The aim of the study was to describe the current rate and determinants of the prescription of antithrombotics in outpatients with permanent atrial fibrillation, with a pre-specified emphasis on the influence of age on the prescription of vitamin K antagonists. METHODS: This was a prospective observational survey in France among 5893 consecutive outpatients with documented permanent atrial fibrillation being seen by 770 physicians from August to December 2002. We recruited physicians from two random lists of general practitioners and cardiologists, respectively, stratified according to their administrative region, from the list of all French private general practitioners and cardiologists. RESULTS: The mean age of patients was 75.8 years. Mean duration since diagnosis of atrial fibrillation was 5.0 years; 31.7% of patients had valvular heart disease and 60.3% hypertension. An antithrombotic was prescribed to 95.5% of patients at the time of consultation. The percentage of patients treated with vitamin K antagonists was 76.4%; it decreased from 86.0% in patients aged 60-70 years to 63.5% in patients aged 80 years or above. On multivariate analysis, high age was a significant predictor (p = 0.001) for the non-prescription of vitamin K antagonists. In patients above 70 years currently receiving an antithrombotic, the probability of prescription of vitamin K antagonists decreased on average by 9.6% per year. CONCLUSIONS: Vitamin K antagonists are administered to most outpatients with permanent atrial fibrillation at high thromboembolic risk seen by French physicians in private practice. However, their use decreases with age

Comparison of fondaparinux with low molecular weight heparin for venous thromboembolism prevention in patients requiring rigid or semi-rigid immobilization for isolated non-surgical below-knee injury

Background: In several small studies, anticoagulant therapy reduced the incidence of venous thromboembolism (VTE) in patients with isolated lower-limb injuries. Objectives: To compare the efficacy and safety of fondaparinux 2.5 mg (1.5 mg in patients with a creatinine clearance between 30 and 50 mL min-1) over nadroparin 2850 anti-factor Xa IU. Patients and Methods: In this international, multicenter, randomized, open-label study, patients with an isolated non-surgical unilateral below-knee injury having at least one additional major risk factor for VTE and requiring, in the Investigator's opinion, rigid or semi-rigid immobilization for 21-45 days with thromboprophylaxis up to complete mobilization received subcutaneously once-daily either fondaparinux or nadroparin. The primary efficacy outcome was the composite of VTE (symptomatic or ultrasonographically detected asymptomatic deep vein thrombosis of the lower limb or symptomatic pulmonary embolism) and death up to complete mobilization. The main safety outcome was major bleeding. Results: We randomized 1349 patients (mean age 46 years): 88.7% had a bone fracture, and 83.8% had a plaster cast fitted (mean duration of immobilization, 34 days). The primary efficacy outcome occurred in 15 of 584 patients (2.6%) in the fondaparinux group and 48 of 586 patients (8.2%) in the nadroparin group (odds ratio, 0.30; 95% confidence interval [CI], 0.15-0.54; P < 0.001). A single major bleed was experienced by fondaparinux-treated patients and none by nadroparin-treated patients. These results were maintained up to the end of follow-up. Conclusions: Fondaparinux 2.5 mg day-1 may be a valuable therapeutic option over nadroparin 2850 anti-FXa IU day-1 for preventing VTE after below-knee injury requiring prolonged immobilization in patients with additional risk factors