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

Abstract

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. 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. 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. 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.